View source for Talk:DNA replication

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==''In vitro'' or automated DNA Synthesis==
Perhaps a section about how DNA is synthesized in the laboratory?

DNA can be synthesized in vitro in the laboratory by thermocyclic or isothermal reactions, these methods are called DNA amplification technologies, mainly include:

'''[1] Thermocycling reactions'''

(1) PCR: Polymerase Chain Reaction, ''Science'',1985

(2) LCR: Ligase Chain Reaction, ''PNAS'',1991

(3) PEAR: Polymerase-Endonuclease Amplification Reaction, ''PLoS One'', 2010

'''[2] Isothermal reactions'''

(1) SDA: Strand Displacement Amplification, ''PNAS'',1992

(2) RCA: Rolling circle amplification, ''Nature Genetics'',1998

(3) LAMP: loop-mediated isothermal amplification, ''NAR'', 2000

(4) HDA: helicase-dependent amplification, ''EMBO reports'', 2004

(5) EXPAR: Exponential amplification reaction, ''PNAS'', 2003


--[[User:Xiaolong7292|Xiaolong7292]] ([[User talk:Xiaolong7292|talk]]) 01:21, 24 August 2011 (UTC)

==recently edited==
I have deleted eukaryotic and prokaryotic replication and put it on its separate pages. There is too many specific differences in theses two topics and I will try to fix the entire page, and organize it better. 03/06/07


shaon==
I think there should also be another section discuss the similiarties between eukaryotic and archeal (and archeal - prokaryotic) DNA replication.  This is important because it deals with evolution and the relatedness between eukaryotes and archea.see it,,

==The Picture==
Shouldn't "ozaki fragments" in the picture (png) be "okazaki fragments"?

rolling circle rep include also

== Easy to break, even easier to fix?   ==

For those of you who know a little more about the licencing factors, how about an explanation of why gene shearing is an accepted technology - do we really know what control mechanisms are involved here ? Or is the inherent capacity of the cell to allow for our meddling, increasingly a source of wonder?

== More info? ==

I looked at this page while doing some homework for my high school biotechnology class and found that it was missing a lot of key information.  For example:

-DNA-B first marks the initiation site for Rep (aka Helicase) to begin "cutting" the DNA
-DNA Gyrase relaxes the supercoiling so that the section of DNA that needs to be replicated is stretched out
-topoisomorase (not sure on spelling) breaks covelant bonds (not sure why, I believe so that Rep has a place to start cutting the strands)

Also, the DNA polymerase referred to in the picture is DNA Polymerase III, and DNA polymerase I is involved in removing the segments between the Okazaki fragments (because they were created by RNA Primase and use RNA nucleotides).  

I would just edit the article, but this is from notes I took from my teachers lecture and I'm not sure whether or not to submit...

----

Topoisomerase and DNA Gyrase are the same enzyme, it just has action in both supercoiling and uncoiling, the fluoroquinolone class of drugs work here actually.  Additionally the picture is an extremely simplified representation of DNA synthesis, rather than edit it I would look for a more complete picture that has Pols 1-3 and a description of what they do and in which direction they do it.  Most Pols have action in both the 3-5 and 5-3 directions.
Pol 1 removes the RNA primers and repairs the region with the last few bases between fragments, ligase is still required for the final 'stitch' between the fragments.

[[User:Etherealmuse|Etherealmuse]] 8:05, 17 Feb 2005 (UTC)

This page also fails to address the obvious question of how the enzymes know how to complete these complex tasks.  As it is, we appear to have an obscurium per obscurius, whereby the propensities of celled creatures are explained by a code, but the actions of enzymes remains a mystery.  Are enzymes also driven by a code or are they automatically tripped, like thermostats?  It is implied by the terminology used if nothing else that decisions are being made by these enzymes.  How do enzymes make decisions?  If there is a Wiki article that begins to explain this, there should be a link.  Neither the enzyme nor the enzyme kinetics article does so.[[User:81.164.252.74|81.164.252.74]] 00:57, 6 August 2006 (UTC)

== Quick Fix ==

The information about the speed of replication in humans had an error that I cleaned up quickly.  It said something to the extent that the an average human chromosome had 6 billion base pairs.  This is wrong, the entirety of the human genome has ~6 billion base pairs, which are themselves arranged in 46 linear chromosomes.  Average chromosome length is not a particularly good reference as it varries considerably (spanning several orders of magnitude).  I cleaned it up to reflect this fact.


-Mr. Knuffke

:Umm. They don't even span a single order of magnitude - the smallest (21) is 47 megabases and the largest (1) is 245 megabases. [[User:Graft|Graft]] 17:30, 8 August 2006 (UTC)

== Why can DNA only be replicated in the 5 - 3 direction? ==

If anyone knows it would probably be worth putting in the article. <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:80.42.104.21|80.42.104.21]] ([[User talk:80.42.104.21|talk]] • [[Special:Contributions/80.42.104.21|contribs]]) 22:13, 7 April 2006</span></small><!-- Template:Unsigned -->

DNA replication proceed in the 5' to 3' direction because the substrates for DNA replication, like RNA polymerization, are 5' nucleoside triphosphates.  In DNA replication the 2' deoxynucleoside triphosphates elongate nacent chains in a template-directed fashon by cleavage of pyrophosphate (the terminal two of three phosphate groups) and transesterification of the remaining phosphate to the free 3- hydroxyl group of the growing chain.  This increases the chain length by one nucleoside, generates pyrophosphate, and reconstitutes another 3' hydroxly group for continued chain elongation. <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:71.128.53.151|71.128.53.151]] ([[User talk:71.128.53.151|talk]] • [[Special:Contributions/71.128.53.151|contribs]]) 15:09, 1 May 2006</span></small><!-- Template:Unsigned -->

Also: The asymmetery of the promoter sequence <small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:83.100.173.204|83.100.173.204]] ([[User talk:83.100.173.204|talk]] • [[Special:Contributions/83.100.173.204|contribs]]) 21:24, 16 October 2006</span></small><!-- Template:Unsigned -->

The reverse sequence 3- to 5- polymerization does occur in nature but would require a different mechanism to dominate the replication process. Prof. Eric Lander (MIT) postulated an explanation of a possible reason natural selection preferred the current order. The reverse process would use contributing molecuels that are more favored for other reactions and thus less available the process.
Watch http://ocw.mit.edu/courses/biology/7-012-introduction-to-biology-fall-2004/video-lectures/

You can not watch more than 10 min of Erics lectures without seeing something that should go in wikipedia. We might be getting a little too technical for wikipedia?? I wouldn't want anyone brain to explode.<small><span class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Scottprovost|Scottprovost]] ([[User talk:Scottprovost|talk]] • [[Special:Contributions/Scottprovost|contribs]]) 20:35, 4 August 2007</span></small><!-- Template:Unsigned -->

:Or you could just look at this picture from Alberts et al. Molecular Biology of the Cell. [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.figgrp.769] I'm not watching the video, I don't know which one you're referring to.  Proofreading of 3'-5' polymerization would require the energy to add the next nucleotide to be stored within triphosphates on the 5' end of the nascent strand. Proofreading would remove this triphosphate, leaving the polymerase at a dead end. In the 5' to 3' direction energy comes from the nucleotide being added, so proofreading breaking the backbone doesn't remove the energy source. 
:I have that figure right here :) ... and that book. To add to the technicality, you could "technically" still polymerize 3'->5' after the proofreading step by activating the 5' phosphate with NAD+ or ATP (similar to how ligase works), but I think nature doesn't want to bother with that. [[User:Jimhsu77479|Jimhsu77479]] ([[User talk:Jimhsu77479|talk]]) 08:50, 25 February 2009 (UTC)
:I maintain that the article needs to be cleaned up. I think that this question is, in a sense, a demonstration of problems in the current article being too "technical" rather than focusing on general mechanisms. [[User:Madprime|Madeleine]] [[User_talk:Madprime|✉]] [[Special:Contributions/Madprime|✍]] 00:05, 5 August 2007 (UTC)

== Prokaryotes and Eukaryotes ==

In my opinion there should be to separate articles for DNA replication in prokaryotes and DNA replication in eukaryotes. At least it should be made clear if prokaryotic DNA replication or eukaryotic is described. I think I know these two processes quite well, but people who read this to learn about DNA transcription will be unnecessarily confused by unclear parts in this article. 

Additionally I think the different eukaryotic polymerases should be mentioned. They are very essential! I suggest copying some of the information from the wikipedia article [[DNA polymerases]].

--[[User:Happy Puppy|Happy Puppy]] 01:38, 2 August 2006 (UTC)

== Too Complicated! ==

I'm a Year 12 biology student, and I had heaps of trouble understanding much of this page. --[[User:218.215.130.252|218.215.130.252]] 10:36, 20 August 2006 (UTC)

== New link to pic and agreement ==

I am suggesting that we add a picture found on the main DNA page, but not found here. The pic to be added to theis page is found here: http://en.wikipedia.org/wiki/Image:Dna-split.png

I do not know how to add pics, so please can either someone tell me, or post a link to where i can learn how to myself on [[User_talk:Stwalkerster | my talk page]].

Just a quick note - I agree with [[218.215.130.252]], It is a bit complicated, so a SIMPLE summary section would be nice. I am doing DNA as part of my GCSEs in the UK.

Thanks

[[User:Stwalkerster|Stwalkerster]] 21:23, 16 September 2006 (UTC)

== Expert ==

I may have failed the DNA unit in Biology, but when I was working on an assignment I got confused.  Is this DNA replication or protein synthesis?

--[[User:Falconus|Falconus]]|[[User talk:Falconus|Talk]] 00:43, 10 October 2006 (UTC)

:It is DNA Replication, although this can sometimes be called "DNA Synthesis" as in the new daughter strands are being synthesised. Protein synthesis involves transcription and translation (I can never remember the diff) and the various RNAs. (t-,m- and r-?) Although I do agree that it needs a good looking over.[[User:GiollaUidir|GiollaUidir]] 13:13, 18 October 2006 (UTC)

::Also, while most of the information does appear to be correct there are no refs given anywhere in the text![[User:GiollaUidir|GiollaUidir]] 13:15, 18 October 2006 (UTC)


== Bidirectionality ==
I was reading the DNA replication, and unable to find information pertaining DNA replication's bidirectionality. I think it is very important to have a section to explain the DNA's bidirectionality replication of a chromosome, as well as a contradictary example of unidirectionality. <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[User:Wolingfeng|Wolingfeng]] ([[User talk:Wolingfeng|talk]] • [[Special:Contributions/Wolingfeng|contribs]]) 22:25, 6 December 2006 (UTC).</small><!-- HagermanBot Auto-Unsigned -->

== Feedback ==

I saw that people were saying how unclear the article was, so I made some changes (but am not done yet). Could someone, preferably someone who is not a molecular biologist or a biochemist :), read few of my changes, so I know if it is understandable to a more general public?

I will make further changes/addition in upcoming days.

also, if someone has more/better ideas, change stuff around!

thanks,
[[User:Svetlana Miljkovic|Svetlana Miljkovic]] 13:12, 20 December 2006 (UTC)
:bit late on the reply, but I am a bsc in biochemistry. I haven't got my textbooks in this country but I will see what I can find. If the tagging on unclear stuff could be focused into individual sections that are problematic, it would be easier to work :) it is hard to identify difficult passages, since this all makes pretty good sense to me... but I have years of training. '''[[User:MrErku|Erk]]'''|[[User:MrErku|Talk]] <sub>-- I like traffic lights --</sub> 13:43, 16 February 2007 (UTC)

==DNA replication video==
http://www.wehi.edu.au/education/wehi-tv/dna/replication.html
This little animation from different angles should be helpful for those interested how DNA replication works. I think we should add this link since Drew Berry made an understandable animation here...--[[User:Artman40|Artman40]] 10:38, 30 December 2006 (UTC)

== Proposed merge ==

The former content of this article appears to be at [[DNA replicate]]. I think it makes most sense to merge it back into this article here. I'm not sure why it was separated out in the first place. - [[User:Tameeria|tameeria]] 19:24, 8 March 2007 (UTC)
 
 I support the merge, Also [[DNA replicate]] seems to be the stronger article.
 It also seems to be 5 years newer then [[DNA replication]] <b>[[User:leafyplant|<span style="color:#009900;">Leafy</span><span style="color:brown;">plant</span>]]</b> 19:32, 8 March 2007 (UTC)

Other candidates for merges include [[replication fork]], [[lagging strand]], and [[leading strand]]. All these are stubs right now and topics that should be part of this article. (As far as DNA replicate goes, it appears that article's content was copied from a former version of this article at the beginning of February this year, after which this article was heavily edited away from its former content so that we have two completely different articles on the same topic now.) - [[User:Tameeria|tameeria]] 19:34, 8 March 2007 (UTC)
:I'd say that [[DNA replicate]] is a product of vandalism.  For some reason its removal from this page was not noticed. I agree that all stubs should probably be folded into this article and turned into redirects.  If someone wishes to expand them later they still have that option. [[User:David D.|David D.]] [[User talk:David D.|(Talk)]] 20:40, 8 March 2007 (UTC)
::Looking at the histories more closely, I now see that the creation of [[DNA replicate]], which was vandalism, is not associated with any major changes to this article. Interestingly, the big changes have been introduced by one wikipedian, Joe ({{user|74.97.31.113}}), and they appear to be good faith edits as seen by the communication [http://en.wikipedia.org/w/index.php?title=User_talk:Tameeria&diff=prev&oldid=110757421 here]. The two major edits include focusing more on the eucaryotic and prokaryotic sections at the expense of initiation, elongation and termination [http://en.wikipedia.org/w/index.php?title=DNA_replication&diff=109727215&oldid=108829984] and the addition of a new section on telomerase.[http://en.wikipedia.org/w/index.php?title=DNA_replication&diff=109984969&oldid=109980229]  After those two edits, from late Feb, most of the constructive edits have been relatively minor.[http://en.wikipedia.org/w/index.php?title=DNA_replication&diff=113510077&oldid=109984969].  [[User:David D.|David D.]] [[User talk:David D.|(Talk)]] 21:06, 8 March 2007 (UTC)
:::I agree that most of the changes appear to be good faith edits and might have been triggered by the existence of two identical pages on the topic. It is still the same topic though, making one page a fork of the other, and some information now is only available in one version versus the other. - [[User:Tameeria|tameeria]] 00:56, 9 March 2007 (UTC)
As a student, I find that having separate entries is extremely useful. [[User:Maristoddard|Maristoddard]] 17:07, 17 July 2007 (UTC)

Since there's been no movement on this, I'll remove the porposed merge tag. I think the topics are probably better as separate entities to simplify this page. &mdash; [[User:Scientizzle|Scien]]''[[User talk:Scientizzle|tizzle]]'' 22:48, 8 October 2007 (UTC)

== Pro- and eukaryotic DNA replication - split or merge? ==

The sections on [[prokaryotic DNA replication]] and [[eukaryotic DNA replication]] also have their own pages. Therefore, these sections could be reduced to a brief summary here. Alternatively, their pages could redirect here, so that the content is not duplicated. I'm not sure what would be the best approach, but given the amount of details, I think it might be best to keep this article general and have the specifics for pro- and eukaryotes in those other articles? - [[User:Tameeria|tameeria]] 19:43, 8 March 2007 (UTC)
:i think a very general entry level article would be great.  Then the details of the processes can be expanded in the specific pro and eu articles.  Certainly a discussion of the differences might be an intereszting aspect that could be developed in this article. [[User:David D.|David D.]] [[User talk:David D.|(Talk)]] 20:36, 8 March 2007 (UTC)
::I was the one who made the intial edits in late feb.  because i thought the original article didnt go into enough details regarding the specifics of replication.  My intention was to leave it as something to work on and keep the main details on DNA replication in eukaryotes, prokaryotes and now the virus, plasmid replication and D-loop replication of mitochondrial dna, all in the section because they deal with replication.  while i can see the reasoning behind splitting it up, talking about all the different forms of replication on other pages, while keeping to the basics on the main page may detract from the main purpose of the article.  if we structure the article better however, i am sure it will be a lot easier to read, regardless of the level of detail.  furthermore, all of my edits i used the voet and voet biochemistry textbook source.  Also, those two pages on pro and eu-karyotic replication is just work someone else stuck on that page that i originally added to the dna replication page:P  - Joe <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/74.114.222.234|74.114.222.234]] ([[User talk:74.114.222.234|talk]]) 09:18, 9 March 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
:::Ok, tonight I edited a lot of the page (i think).  I sectioned it off, added a bunch of new information on the clamp loader, regulation of plasmid replication.  I also added all the info from leading, lagging, d-loop (with my own edits), rolling circle, and replication fork pages into this one...so now we should have a more complete page. <small>—The preceding [[Wikipedia:Sign your posts on talk pages|unsigned]] comment was added by [[Special:Contributions/74.114.222.234|74.114.222.234]] ([[User talk:74.114.222.234|talk]]) 11:02, 9 March 2007 (UTC).</small><!-- HagermanBot Auto-Unsigned -->
::Cool, thanks for your edits, Joe! It is much better structured now. Including information from biochemistry and molecular biology textbooks is good. However, since DNA replication is something kids hear about in highschool and might look up on Wikipedia, this article needs to have clearly structured basic information on the topic as well to cater to both the average highschool student and college science majors. I think it's much more balanced now. - [[User:Tameeria|tameeria]] 14:14, 9 March 2007 (UTC)

It still needs a lot of work, and a lot of new sections need to be added to it.  At the moment, I study microbiology at the university of guelph.  But a lot of sections still need to be edited for more "completeness" because I either pulled them right from the wikipedia page (like d-loop, lagging/leading/replication fork) and need to be cleaned up.  sorry for my bad grammer, ive been up all night doing final edits on my h2ax paper so im just a little grammered out! but I think the next major section should be archea and replication in bacterial and eukaryotic viruses.  As for the way eukaryotic and prokaryotic replication is structured..i think its fine as it is now (maybe a section pointing to the mechanism of elongation and a blurb explaining that) and then the pages that you started with it could be further detailed later on...i think we also need some way to talk about checkpoints in S-phase in the eukaryotic cell cycle with regards to stalled replication forks and double strand breaks and other forms of DNA damage that can occur in DNA replication..nothing huge, but something pointing to DNA repair (And hopefully if i get a good grade on my paper, ill turn it into a wikipedia page!)..anyways, enough of my blabbing - Joe

== DNA synthesis - disambig? ==

Based on previous comments, it appears the redirect of [[DNA synthesis]] to this article might be ambiguous. Besides cellular DNA replication, there is also enzymatic ''in vitro'' DNA replication ([[Polymerase chain reaction]]) and chemical DNA synthesis (oligonucleotide synthesis). Should DNA synthesis be disambiguated? Also, information on chemical DNA synthesis was requested, but I think it's beyond the scope of this article as it is not exactly replication, but ''de-novo'' synthesis via chemistry. What would be a good title for a page for that topic? Should it be at [[DNA synthesis]], or should that be purely a disambigation page with the other maybe at [[Oligonucleotide synthesis]]? - [[User:Tameeria|tameeria]] 19:49, 8 March 2007 (UTC)

:I've created an article at [[oligonucleotide synthesis]] and added a disambiguation page for [[DNA synthesis]]. If anyone has anything to add, please feel free. - [[User:Tameeria|tameeria]] 17:35, 14 April 2007 (UTC)

== Major problems ==
This page seems to be suffering from some major issues. In my opinion, it would be best to make the distinction between prokaryotic and eukaryotic DNA replication more obvious, preferably by splitting everything except the introduction in a prokaryotic and a eukaryotic section.
Also, it doesn't have in-line references. Since those are preferred for [[WP:GA|good article]] status, I will add those in my edits. If the previous sources could be converted to in-line references it would be great. [[User:Sakkura|Sakkura]] 18:18, 13 July 2007 (UTC)

==Focus on common mechanisms? ==

I feel these eubacteria / eukaryotes / archaea sections are very heavy on naming of specific enzymes rather than focusing on general mechanisms. I think it would be nice to reorganize this article with more general mechanisms of DNA replication rather than throwing case studies at the reader. I was looking at chapter 15 in DNA Replication 2nd ed (Kornberg & Baker) which lists some basic rules of replication:
*semiconservative
*initiation occurs at specific sequences in DNA, called origins
*replication continues uni or bi-directionally along replication forks
*helicase is nearly always necessary for progress of the fork
*stands elongate in 5' to 3' direction / replication is generally semidiscontinuous / okazaki fragments
*short fragments of RNA serve as primers

Rather than throw three different cases at the reader, we could talk about these common features. If the differences between eukaryote and eubacteria and archaea can be boiled down into a paragraph, this would be ideal.

It's not that the current material is wrong, but it's way, way too technical. I've got biology background and my eyes just glaze over when I read: ''"Activation of the complex occurs in S-phase and requires Cdk2-Cyclin E and Ddk. The activation process begins with the addition of Mcm10 to the pre-RC, which displaces Cdt1. Following this, Ddk phosphorylates Mcm3-7, which activates the helicase."''

I feel bad throwing material away, but I feel like the page needs a rewrite that focuses on common mechanisms rather than separately describing a couple of very detailed biochemical cases. I'd like to start working on it myself, please let me know if I shouldn't spend time on it. [[User:Madprime|Madeleine]] [[User_talk:Madprime|✉]] [[Special:Contributions/Madprime|✍]] 20:25, 1 August 2007 (UTC)
:I too would prefer if this particular article confines itself to the general mechanisms, without going into too much detail about all the specifics. Separate articles can be written about eubacteria / eukaryotes / archae can be linked from here, and things can be dealt with in more detail there. - [[User:Twooars|<span style="color:Indigo;">'''Two'''</span>]][[User_Talk:Twooars|<span style="color:DarkViolet;">'''Oars'''</span>]] 20:37, 1 August 2007 (UTC)

== TOO COMPLEX ==
Hey I don't know who is writing this article, but I am in 11th grade and I didn't understand much from this, remember that a lot of people check this page and has to be understandable for everyone!--[[User:189.135.137.8|189.135.137.8]] 20:54, 6 October 2007 (UTC)
:True. But it is a complex topic. :) But seriously, we have to strike a balance between comprehensive coverage and keeping it simple. A difficult thing to achieve. :-/ Note that it would be even more difficult to understand, if not for all the wikilinks. And a lot of the (really) gory details are pushed away to separate articles. - [[User:Twooars|<span style="color:Indigo;">'''Two'''</span>]][[User_Talk:Twooars|<span style="color:DarkViolet;">'''Oars'''</span>]] [[User:Twooars/Editor review 2|<small>(Rev)</small>]] 21:25, 6 October 2007 (UTC)
::There is a [http://simple.wikipedia.org/wiki/DNA_replication Simple Wikipedia] version of the page, but I doubt it'll go into enough detail for 11th grade. --[[User:Gwib|Gwib]] ([[User talk:Gwib|talk]]) 20:41, 19 February 2008 (UTC)
:I disagree.  I love it.  [[User:Anon lynx|Stephen Charles Thompson]] ([[User talk:Anon lynx|talk]]) 21:08, 24 April 2009 (UTC)

I disagree also.  I'm a 3rd year Med Student who just couldn't grasp this concept last year in class.  HOWEVER, after reading this article, utilizing the FANTASTIC visual aides, plus visiting the word links that I didn't understand... It pulled it all together for me.  The lightbulb finally turned on for me.  I am so grateful, thank you.  USMLE Step 1 here I come!  <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/12.235.208.2|12.235.208.2]] ([[User talk:12.235.208.2|talk]]) 15:17, 13 November 2011 (UTC)</span><!-- Template:Unsigned IP --> <!--Autosigned by SineBot-->

== Draft of new version of article ==

I've finally put together [[User:Madeleine_Price_Ball/Draft|a draft of a new version of this article]] that focuses more on common mechanisms. I've thrown away a lot of the protein naming. It would be wonderful if anyone interested could take a look at the article, make corrections, suggestions and/or mark it up with <nowiki>{{fact}}</nowiki> and <nowiki>{{what}}</nowiki> tags (I tend to write things in one fell swoop and it's hard to know which sentences should get references placed on them so it'd be nice if someone else marked which points should be referenced). Tell me what you think and maybe I can copy it over here and replace the current article. [[User:Madeleine_Price_Ball|Madeleine]] [[User_talk:Madeleine_Price_Ball|✉]] [[Special:Contributions/Madeleine_Price_Ball|✍]] 19:16, 3 March 2008 (UTC)
:No one said anything so I replaced the article with my version. [[User:Madeleine_Price_Ball|Madeleine]] [[User_talk:Madeleine_Price_Ball|✉]] [[Special:Contributions/Madeleine_Price_Ball|✍]] 01:56, 6 March 2008 (UTC)
::Thanks for your hard work re-writing the article.  I had the article watched for a while now since I thought it needed great improvement but never personally got around to it.  The writing is quite excellent and will hopefully be easy for a non-scientist to understand.  I think with a few more referneces the article should go for GA status.  Let me know if you need any help.  [[User:Biomedeng|Biomedeng]] ([[User talk:Biomedeng|talk]]) 02:28, 6 March 2008 (UTC)

== DNA replication accuracy? ==

In the wikipedia article it says:
"DNA polymerases are generally extremely accurate, making less than one error for every million nucleotides added."

But according to one of the sources cited:

"As discussed at the beginning of this chapter, the fidelity of copying DNA during replication is such that only about 1 mistake is made for every 10^9 nucleotides copied."

That makes it less than an error in 1 billion nucleotides added, not 1 million. If people agree can we change it according to the source? [http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.section.754]  <small>—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Medfreak|Medfreak]] ([[User talk:Medfreak|talk]] • [[Special:Contributions/Medfreak|contribs]]) 13:08, 22 August 2008 (UTC)</small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->

:We'd need a citation here. The error rate for Taq and other thermostable polymerases is 10^-5, or at best 10^-6. The "1 in a billion" number is for the entire replication machinery - that is, the entire holoenzyme, mismatch repair systems, etc., which includes a lot more than just the polymerase. [[User:Graft|Graft]] | [[User_talk:Graft|talk]] 09:08, 4 November 2008 (UTC)

== Name of Active Site? ==
I vaguely remember learning about a name for the active site where replication was occuring.  Isn't there a name for this region of splitting and replicating?  Isn't there a sub-organelle or micro-organelle responsible for this? [[User:Anon lynx|Stephen Charles Thompson]] ([[User talk:Anon lynx|talk]]) 21:12, 24 April 2009 (UTC)
:Do you mean "replication fork"? There's no specific organelle devoted to it - it happens wherever the DNA is lying around in the nucleus. [[User:Graft|Graft]] | [[User_talk:Graft|talk]] 21:53, 24 April 2009 (UTC)

== Merge from [[Replication fork]] ==

It was previously mentioned in this discussion, but now that the same discussion in that other article [[Talk:Replication fork]], it's worth to bring up again. It says almost exactly the same as the section [[DNA replication#The replication fork]] and could conveniently be redirected directly to that section. Thus, there's no use reading ''Replication fork'' after reading this article, and starting with reading ''Replication fork'' without getting it in its context is also inefficient. [[User:Mikael Häggström|Mikael Häggström]] ([[User talk:Mikael Häggström|talk]]) 18:54, 21 May 2009 (UTC)

After reading both articles, the similarity is quite apparent; the merging of these two pages makes sense in terms of completeness. However, there was an earlier discussion about the simplicity of this article. As an 11th grader I can easily understand the plight of several High School Biology students, and for their sake, I feel that these articles should remain separate. If someone needs to go deeper, (as I did) it is easy enough to follow the link and skim the repetitious material. --[[User:Adam zappul|Adam zappul]] ([[User talk:Adam zappul|talk]]) 03:54, 6 June 2010 (UTC)

I think that the merging does make a lot of sense, being a "High School Biology student," as you put it.  The replication fork is in the very first picture in the article, and is the beginning of DNA replication, so I would say it would make more sense to merge the two.  --''~[[User:Tajjet|taj]]<sub>[[User_talk:Tajjet|t]]</sub>'' 16:41, 18 November 2010 (UTC)

Sorry for not having an account, but I figured my voice needed to be heard. I'm currently studying for midterms in my high school and this is on the biology test and I '''really''' need this. Please keep and don't merge :) [[Special:Contributions/76.250.195.66|76.250.195.66]] ([[User talk:76.250.195.66|talk]]) 16:12, 18 January 2011 (UTC)

== Unclear sentences ==

We have a few unclear sentences here

# "The energetics of this process also help explain the directionality of synthesis - if DNA were synthesized in the 3' to 5' direction, the energy for the process would come from the 5' end of the growing strand rather than from free nucleotides." So be it. Where is the problem here?
# "If the 5' nucleotide needs to be removed during proofreading, the triphosphate end is lost. Hence, the energy source that usually provides energy to add a new nucleotide is also lost." With what effect?

[[User:Debresser|Debresser]] ([[User talk:Debresser|talk]]) 14:38, 4 September 2009 (UTC)

:The problem is that if the triphosphates are on the growing strand and not on the free nucleotides, proof-reading by removing a mismatched terminal nucleotide is problematic: Once a nucleotide is added, the triphosphate is lost and a single phosphate remains on the backbone between the new nucleotide and the rest of the strand. If that nucleotide is mismatched, you have to remove it and then only have one phosphate at the end of the "growing strand", not a triphosphate that is needed to attach a new nucleotide. So it's stuck and can't grow anymore. 
:If the triphosphates at each step are taken from the free nucleotides, not the polymerized strand, you don't get stuck in this way.
:If you understand now and can think of what to add/change to clarify this explanation, that would be great!  --  [[User:Madeleine_Price_Ball|Madeleine]] [[User_talk:Madeleine_Price_Ball|✉]] [[Special:Contributions/Madeleine_Price_Ball|✍]] 16:31, 4 September 2009 (UTC)

:: I'm sorry, but I don't. Perhaps an expert with a talent for explaining difficult things in simple words could do this. Or we could remove it, if it is too technical for this article. [[User:Debresser|Debresser]] ([[User talk:Debresser|talk]]) 19:49, 22 September 2009 (UTC)

== Recommend link to existing Wiki topic ==

In the section under Origins of Replication, there is a reference to Okazaki fragments as follows: "Once strands are separated, RNA primers are created on the template strands. More specifically, the leading strand receives one RNA primer per active origin of replication while the lagging strand receives several; these several fragments of RNA primers found on the lagging strand of DNA are called Okazaki fragments, named after their discoverer."

It seems to me that it would be beneficial to hyperlink the term "Okazaki fragments" to the Wiki article of the same name....also possibly pluralizing the word "discoverer", since in the Okazaki fragment Wiki article two Okazakis are credited with their discovery.  Just a couple of thoughts after reading the first few paragraphs of the article.
[[Special:Contributions/66.205.144.176|66.205.144.176]] ([[User talk:66.205.144.176|talk]]) 11:12, 6 September 2010 (UTC)introspectacle

== Video clip ==

[[File:DNA replication.theora.ogv|right|200px]]I have generated a short (52 seconds / 8.5 MB) clip showing the prime phases of DNA replication.  Please make comments / suggestions as to any improvement.  (Not suitable for dial-up lines) --[[User:Cookatoo.ergo.ZooM|Cookatoo.ergo.ZooM]] ([[User talk:Cookatoo.ergo.ZooM|talk]]) 08:05, 4 November 2010 (UTC)
File size minimised to 1.11 MB to reduce problems at load and view.  --[[User:Cookatoo.ergo.ZooM|Cookatoo.ergo.ZooM]] ([[User talk:Cookatoo.ergo.ZooM|talk]]) 20:00, 14 November 2010 (UTC)
: Very neat!  I support replacing the lead image with this video, which is in line with Wikipedia's approach to [[WP:BOLD | boldness]] and will likely generate more feedback.  While it contains jargon like 'helicase' and 'polymerase', I think those terms are adequately contextualized, and could be wikilinked in a brief caption.  More of this type of simple audio-video content is something that could greatly benefit science articles. [[User:Emw|Emw]] ([[User talk:Emw|talk]]) 04:17, 19 November 2010 (UTC)

== WP:GA Candidate ==

I believe the article is good enough to be a [[WP:GP|Good Article]]. However not being a major contributor, it is mandatory for regular editors to be consulted prior to submission as I propose. Thoughts? --[[User:HarshAJ|HarshAJ]] <sup>[[User_talk:HarshAJ|(Talk)]]([[Special:Contributions/HarshAJ|Contribs]])</sup> 14:00, 13 December 2012 (UTC)
:I personally would disagree, since I believe the article is too brief, but I notice that several commentators on this talk page think that the coverage in this article is just about right. I am thus nominating the article for GA. Assuming that a fair and conscientious GA reviewer takes on this article, the close attention and scrutiny will be good for it. [[User:Stigmatella aurantiaca|Stigmatella aurantiaca]] ([[User talk:Stigmatella aurantiaca|talk]]) 00:39, 14 December 2012 (UTC)
::This is the kind of article I'd be interested in reviewing, but I think it would have problems making it out of the starting blocks with the large number of unreferenced paragraphs. I recommend withdrawing and getting the sourcing up to par. It might be possible to do this quickly, as everything should be citable to an undergrad-level textbook, but probably would be a more enjoyable task without any time pressure. [[User:Sasata|Sasata]] ([[User talk:Sasata|talk]]) 02:13, 14 December 2012 (UTC)
:::Good idea! [[User:Stigmatella aurantiaca|Stigmatella aurantiaca]] ([[User talk:Stigmatella aurantiaca|talk]]) 05:32, 14 December 2012 (UTC)

=== Standardise ===
I noted in section 'Origin' both m-dashes and hyphens were used. It would be best to standardise on n-dashes throughout if hyphens are not appropriate. Style guide gives chapter and verse, and should be read. Sooner or later in the GA/FA process it has to be done, so best to do these things right away. 

Likewise, to add refs to unref'd paras, select one or two standard texts and stick to them. I notice you have refs to the out-of-date-edition of The Molecular Biology of the Cell. They should be adjusted to the latest edition, including the new pages numbers. 

Boring, but necessary. [[User:Macdonald-ross|Macdonald-ross]] ([[User talk:Macdonald-ross|talk]]) 12:54, 19 December 2012 (UTC)

== RNA primer addition on the lagging strand ==

Currently (this exact phrasing is a result of my own recent edits, but the article was to this effect before my edits) we say:
"The leading strand receives one RNA primer while the lagging strand receives several."
Is the later part of this sentence accurate? Are the RNA primers added to the lagging strand as a group of several, or one at a time as the lagging strand is exposed? It is possible that with the initial formation of the pre-replication complex, several RNA primers are added. But since most Okazaki fragments are a few hundred base pairs and the pre-replication complex exposes about the same number of base pairs on the lagging strand, I would imagine only one RNA primer could be added initially. Once replication is proceeding, I would think primers would be added continuously. Thanks![[User:Scientific29|Scientific29]] ([[User talk:Scientific29|talk]]) 18:20, 20 April 2013 (UTC)

== Talk page archive ==

Can I ask Miza bot to archive this talk page? The how-to page says get consensus first...[[User:Scientific29|Scientific29]] ([[User talk:Scientific29|talk]]) 18:21, 20 April 2013 (UTC)

:OK with me. Most of these talk comments date from years ago. This article has an uncomfortable number of '''current''' inaccuracies that need to be addressed. It's surprising to me how many this article has, given its importance and the number of eyes that have presumably been checking and verifying it over the years. [[User:Stigmatella aurantiaca|Stigmatella aurantiaca]] ([[User talk:Stigmatella aurantiaca|talk]]) 23:13, 21 April 2013 (UTC)
::Yes this seems like an important and awful article. I guess my first question is, what do we want it to be compared to, say, [[Prokaryotic DNA repication]] and [[Eukaryotic DNA replication]]? I have a elementary understanding of [[DNA replication]] and could certainly improve this article if it were intended to be a general introduction to the topic. However, I don't really know enough to compare and contrast prokaryotic and eukaryotic replication. I'm more of a translation guy. [[User:Scientific29|Scientific29]] ([[User talk:Scientific29|talk]]) 23:57, 21 April 2013 (UTC)

== Merge from Replication fork II ==

Merge has been done, but the result is not completely satisfying: I find the article very long and complex and tiring to read, while some points are still not sufficiently explained. For instance I came here looking for details about "stalled replication forks", but the search returns several articles, each of them using the term but without the simplest explanation, and the one place where such an explanation could be expected, precisely "Replication Fork", does indeed mention stalled forks, but with confusing expressions like <I>"If replication forks stall [..] daughter strands have nick obtained un-replicated sites"</I>, which are not really helpful. <BR>
It would be useful maybe to have a shorter, more readable section "Replication Fork" in this article, with a link to a full main article "Replication Fork", where the subject could be treated really exhaustively, just like it is done in many historical articles in WP.<BR>
This way someone could also develop the subsection "Dynamics at the replication fork", which is still somewhat lapidary and rather confusing (what are clamps necessary for? Sentences like <I>Clamp-loading proteins are used to initially load the clamp</I> are not really adding information. And so on), maybe because nobody dares to overload the article even more. [[Special:Contributions/194.174.73.33|194.174.73.33]] ([[User talk:194.174.73.33|talk]]) 17:45, 21 March 2016 (UTC) Marco Pagliero Berlin

==Assessment comment==
{{Substituted comment|length=391|lastedit=20070219034041|comment=The article is generally scientifically correct, but it badly needs to be translated into plainer English. &ndash; [[User:ClockworkSoul|Clockwork]][[User_talk:ClockworkSoul|<b>Soul</b>]] 04:48, 7 November 2006 (UTC)

Changing the rating to "top" as this is high school/SAT biology topic and a central mechanism of molecular biology. - [[User:Tameeria|tameeria]] 03:40, 19 February 2007 (UTC)}}
Substituted at 12:40, 29 April 2016 (UTC)

Overall, This article is very interesting and the sources are good .
Fatin [[User:Fatin Hamd|Fatin Hamd]] ([[User talk:Fatin Hamd|talk]]) 04:20, 9 September 2018 (UTC)

== Ribopolymerase and the origins of life ==
try to create ribopolymerase in the lab - a catalyst which acts as ribosome and polymerase ...  <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/2A02:587:4109:4C00:1819:DEC2:D0BC:9571|2A02:587:4109:4C00:1819:DEC2:D0BC:9571]] ([[User talk:2A02:587:4109:4C00:1819:DEC2:D0BC:9571|talk]]) 00:14, 29 August 2016 (UTC)</small> <!--Autosigned by SineBot-->

== Replication vs Duplication ==

The article makes one reference to the DNA being duplicated (use ctrl-f and search for it to see what I mean) and many references to it being replicated (and is titled as such). Should the single reference to duplication be changed to replication to avoid confusion, or are the terms the same in this context? I'm not well versed on the topic but am confused by the difference and cannot find much online - the article compounds this confusion by mixing the two terms  <!-- Template:Unsigned --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:MattWhitelock0|MattWhitelock0]] ([[User talk:MattWhitelock0#top|talk]] • [[Special:Contributions/MattWhitelock0|contribs]]) 14:12, 28 April 2018 (UTC)</small> <!--Autosigned by SineBot-->

== Something is going on with helicase and topisomerase ==

In the 'dynamics at the replication fork' section topoisomerase and helicase were mixed up (which can be verified by looking at their wikipedia pages, which say that topoisomerase unwinds while helicase cuts). But there is  still a thing about DNA gyrase there which is a form of topoisomerase https://www.ncbi.nlm.nih.gov/pubmed/1657531 . And the DNA gyrase page also says that helicase unwinds the DNA. https://en.wikipedia.org/wiki/DNA_gyrase . I don't know enough to confidently edit this so we need someone to fix this.  <!-- Template:Unsigned --><small class="autosigned">—&nbsp;Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:RotundCat|RotundCat]] ([[User talk:RotundCat#top|talk]] • [[Special:Contributions/RotundCat|contribs]]) 00:07, 24 August 2018 (UTC)</small> <!--Autosigned by SineBot-->

== A Commons file used on this page has been nominated for deletion ==
The following Wikimedia Commons file used on this page has been nominated for deletion:
* [[commons:File:DNA replication en.svg|DNA replication en.svg]]<!-- COMMONSBOT: discussion | 2019-05-14T07:53:16.717798 | DNA replication en.svg -->
Participate in the deletion discussion at the [[commons:Commons:Deletion requests/File:DNA replication en.svg|nomination page]]. —[[User:Community Tech bot|Community Tech bot]] ([[User talk:Community Tech bot|talk]]) 07:53, 14 May 2019 (UTC)

== Ambiguous language- ==

Last sentence under '''DNA structure:''' "The nucleotides on a single strand can therefore be used to reconstruct nucleotides on a newly synthesized partner strand"
If the nucleotides on the parent strand are used to construct the partner strand, then the parent strand would be all gone by the time the partner strand was synthesized. No net DNA synthesis would be occurring. To avoid this misunderstanding, say "can be used as a template to direct the order of nucleotides being added to the growing partner strand"? [[User:Eaberry|Eaberry]] ([[User talk:Eaberry|talk]]) 18:21, 2 June 2021 (UTC)

==Wiki Education assignment: Molecular Genetics==
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<span class="wikied-assignment" style="font-size:85%;">— Assignment last updated by [[User:Jellyfish829|Jellyfish829]] ([[User talk:Jellyfish829|talk]]) 11:29, 13 December 2023 (UTC)</span>

==Wiki Education assignment: Genetics==
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