View source for Glycogen branching enzyme

{{short description|Mammalian protein involved in glycogen production}}
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{{Infobox_gene}} 
{{infobox enzyme
| Name       = Glycogen branching enzyme
| EC_number  = 2.4.1.18
| CAS_number = 9001-97-2
| GO_code    = 0003844
| image      =
| width      = 
| caption    =  
}}
'''1,4-alpha-glucan-branching enzyme''', also known as '''brancher enzyme''' or '''glycogen-branching enzyme''' is an [[enzyme]] that in humans is encoded by the ''GBE1'' [[gene]].<ref name="entrez">{{cite web | title = Entrez Gene: glucan (1,4-alpha-), branching enzyme 1| url = https://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=retrieve&list_uids=2632| access-date = 2011-08-30}}</ref>

'''Glycogen branching enzyme''' is an [[enzyme]] that adds branches to the growing glycogen molecule during the synthesis of [[glycogen]], a storage form of [[glucose]]. More specifically, during glycogen synthesis, a glucose 1-phosphate molecule reacts with uridine triphosphate (UTP) to become UDP-glucose, an activated form of glucose. The activated glucosyl unit of UDP-glucose is then transferred to the hydroxyl group at the C-4 of a terminal residue of glycogen to form an α-1,4-[[glycosidic linkage]], a reaction catalyzed by [[glycogen synthase]]. Importantly, glycogen synthase can only catalyze the synthesis of α-1,4-glycosidic linkages. Since glycogen is a readily mobilized storage form of glucose, the extended glycogen polymer is branched by glycogen branching enzyme to provide glycogen breakdown enzymes, such as [[glycogen phosphorylase]], with many terminal residues for rapid degradation. Branching also importantly increases the solubility and decreases the osmotic strength of glycogen.<ref name=Berg>{{cite book| vauthors = Berg J |title=Biochemistry | edition = Seventh|year=2012|publisher=W.H. Freeman and Company|pages=627–630}}</ref>

The protein encoded by this gene is a [[glycogen]] branching [[enzyme]] that [[catalyzes]] the transfer of alpha-1,4-linked [[glucosyl]] units from the outer end of a glycogen chain to an alpha-1,6 position on the same or a neighboring glycogen chain. Branching of the chains is essential to increase the [[solubility]] of the glycogen [[molecule]] and, consequently, in reducing the [[osmotic pressure]] within [[Cell (biology)|cells]]. The highest levels of this enzyme are found in [[liver]] and [[muscle]] cells. [[Mutations]] in this gene are associated with [[glycogen storage disease type IV]] (also known as Andersen's disease).

==Nomenclature==
This enzyme belongs to the family of [[transferase]]s, to be specific, those glycosyltransferases that transfer [[hexose]]s ([[hexosyltransferase]]s). The [[List of enzymes|systematic name]] of this enzyme class is 1,4-alpha-D-glucan:1,4-alpha-D-glucan 6-alpha-D-(1,4-alpha-D-glucano)-transferase. Other names in common use include branching enzyme, amylo-(1,4→1,6)-transglycosylase, Q-enzyme, alpha-glucan-branching glycosyltransferase, amylose isomerase, enzymatic branching factor, branching glycosyltransferase, enzyme Q, glucosan transglycosylase, [[1,4-alpha-glucan branching enzyme 1]], plant branching enzyme, alpha-1,4-glucan:alpha-1,4-glucan-6-glycosyltransferase, and starch branching enzyme. This enzyme participates in [[starch]] and [[sucrose]] metabolism.

==Gene==
GBE is encoded by the ''GBE1'' [[gene]].<ref name="entrez" /><ref name="NCBI GBE1">{{cite web| work = National Center for Biotechnology Information|title=GBE1 glucan (1,4-alpha-), branching enzyme 1 [ Homo sapiens (human) ]|url=https://www.ncbi.nlm.nih.gov/gene?cmd=retrieve&list_uids=2632|publisher=US. National Library of Medicine}}</ref><ref name="OMIM GBE1">{{cite web| work = Online Mendelian Inheritance in Man|title=Glycogen Branching Enzyme; GBE1|url=http://www.omim.org/entry/607839|publisher=Johns Hopkins University}}</ref><ref name="Genetics Home Reference GBE1">{{cite web|last=Genetics Home Reference|title=GBE1|url=http://ghr.nlm.nih.gov/gene/GBE1|publisher=U.S. National Library of Medicine}}</ref>

Through [[Southern blot]] analysis of DNA derived from human/rodent somatic cell hybrids, GBE1 has been identified as an [[autosomal]] gene located on the short arm of chromosome 3 at position 12.3.<ref name="NCBI GBE1" /><ref name="OMIM GBE1" /><ref name="Genetics Home Reference GBE1" /><ref name="Thon Paper on Gene Location GBE">{{cite journal | vauthors = Thon VJ, Khalil M, Cannon JF | title = Isolation of human glycogen branching enzyme cDNAs by screening complementation in yeast | journal = The Journal of Biological Chemistry | volume = 268 | issue = 10 | pages = 7509–7513 | date = April 1993 | pmid = 8463281 | doi = 10.1016/S0021-9258(18)53204-X | doi-access = free }}</ref>  The human GBE gene was also isolated by a function complementation of the Saccharomyces cerevisiae GBE deficiency.<ref name="Thon Paper on Gene Location GBE"/> From the isolated cDNA, the length of the gene was found to be approximately 3 kb.<ref name="Thon Paper on Gene Location GBE"/> Additionally, the coding sequence was found to comprise 2,106 base pairs and encode a 702-amino acid long GBE. The molecular mass of human GBE was calculated to be 80,438 Da.<ref name="Thon Paper on Gene Location GBE"/>

== Structure ==
[[File:E. Coli Glycogen Branching Enzyme.png|thumb|upright=1.35|Structure of glycogen branching enzyme found in E. Coli]]
Glycogen branching enzyme belongs to the [[α-amylase]] family of enzymes, which include α-amylases, pullulanas/isoamylase, cyclodextrin glucanotransferase (CGT), and branching enzyme.<ref name="E. Coli X-ray Crystallographic Structure">{{cite journal | vauthors = Abad MC, Binderup K, Rios-Steiner J, Arni RK, Preiss J, Geiger JH | title = The X-ray crystallographic structure of Escherichia coli branching enzyme | journal = The Journal of Biological Chemistry | volume = 277 | issue = 44 | pages = 42164–42170 | date = November 2002 | pmid = 12196524 | doi = 10.1074/jbc.m205746200 | series = 44 | doi-access = free }}</ref><ref name="Crystal Structure of Mtb">{{cite journal | vauthors = Pal K, Kumar S, Sharma S, Garg SK, Alam MS, Xu HE, Agrawal P, Swaminathan K | title = Crystal structure of full-length Mycobacterium tuberculosis H37Rv glycogen branching enzyme: insights of N-terminal beta-sandwich in substrate specificity and enzymatic activity | journal = The Journal of Biological Chemistry | volume = 285 | issue = 27 | pages = 20897–20903 | date = July 2010 | pmid = 20444687 | pmc = 2898361 | doi = 10.1074/jbc.M110.121707 | doi-access = free }}</ref>  Shown by x-ray crystallography, glycogen branching enzyme has four marginally asymmetric units each that are organized into three domains: an amino-terminal domain, involved in determining the length of the chain transfer, a carboxyl-terminal domain, involved in substrate preference and catalytic capacity, and a central (α/β) barrel catalytic domain.<ref name="E. Coli X-ray Crystallographic Structure" /><ref>{{cite journal | vauthors = Matsuura Y, Kusunoki M, Harada W, Kakudo M | title = Structure and possible catalytic residues of Taka-amylase A | journal = Journal of Biochemistry | volume = 95 | issue = 3 | pages = 697–702 | date = March 1984 | pmid = 6609921 | doi = 10.1093/oxfordjournals.jbchem.a134659 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Buisson G, Duée E, Haser R, Payan F | title = Three dimensional structure of porcine pancreatic alpha-amylase at 2.9 A resolution. Role of calcium in structure and activity | journal = The EMBO Journal | volume = 6 | issue = 13 | pages = 3909–3916 | date = December 1987 | pmid = 3502087 | pmc = 553868 | doi = 10.1002/j.1460-2075.1987.tb02731.x }}</ref><ref>{{cite journal | vauthors = Devillers CH, Piper ME, Ballicora MA, Preiss J | title = Characterization of the branching patterns of glycogen branching enzyme truncated on the N-terminus | journal = Archives of Biochemistry and Biophysics | volume = 418 | issue = 1 | pages = 34–38 | date = October 2003 | pmid = 13679080 | doi = 10.1016/S0003-9861(03)00341-2 }}</ref> The amino-terminal domain consists of 128 residues arranged in seven β-strands, the carboxyl-terminal domain with 116 residues also organized in seven β-strands, and the (α/β) barrel domain with 372 residues. While the central (α/β) barrel domain is common in members of the α-amylase family, numerous variations exist between the various barrel domains. Additionally, there are striking differences between the loops connecting elements of the secondary structure among these various α-amylase members, especially around the active site. In comparison to the other family members, glycogen binding enzyme has shorter loops, which result in a more open cavity, favorable to the binding of a bulkier substrate such as branched sugar. Through primary structure analysis and the x-ray crystallographic structures of the members of the α-amylase family, seven residue were conserved, Asp335, His340, Arg403, Asp 405, Glu458, His525, and Asp526 (E coli. numbering). These residues are implicated in catalysis and substrate binding.<ref name="E. Coli X-ray Crystallographic Structure" />

Glycogen binding enzymes in other organisms have also been crystallized and structurally determined, demonstrating both similarity and variation to GBE found in [[Escherichia coli]].<ref>{{cite journal | vauthors = Kuriki T, Stewart DC, Preiss J | title = Construction of chimeric enzymes out of maize endosperm branching enzymes I and II: activity and properties | journal = The Journal of Biological Chemistry | volume = 272 | issue = 46 | pages = 28999–29004 | date = November 1997 | pmid = 9360973 | doi = 10.1074/jbc.272.46.28999 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Palomo M, Pijning T, Booiman T, Dobruchowska JM, van der Vlist J, Kralj S, Planas A, Loos K, Kamerling JP, Dijkstra BW, van der Maarel MJ, Dijkhuizen L, Leemhuis H | title = Thermus thermophilus glycoside hydrolase family 57 branching enzyme: crystal structure, mechanism of action, and products formed | journal = The Journal of Biological Chemistry | volume = 286 | issue = 5 | pages = 3520–3530 | date = February 2011 | pmid = 21097495 | pmc = 3030357 | doi = 10.1074/jbc.m110.179515 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Santos CR, Tonoli CC, Trindade DM, Betzel C, Takata H, Kuriki T, Kanai T, Imanaka T, Arni RK, Murakami MT | title = Structural basis for branching-enzyme activity of glycoside hydrolase family 57: structure and stability studies of a novel branching enzyme from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 | journal = Proteins | volume = 79 | issue = 2 | pages = 547–557 | date = February 2011 | pmid = 21104698 | doi = 10.1002/prot.22902 | s2cid = 25862890 }}</ref><ref>{{cite journal | vauthors = Noguchi J, Chaen K, Vu NT, Akasaka T, Shimada H, Nakashima T, Nishi A, Satoh H, Omori T, Kakuta Y, Kimura M | title = Crystal structure of the branching enzyme I (BEI) from Oryza sativa L with implications for catalysis and substrate binding | journal = Glycobiology | volume = 21 | issue = 8 | pages = 1108–1116 | date = August 2011 | pmid = 21493662 | doi = 10.1093/glycob/cwr049 | doi-access =  }}</ref>

== Function ==
[[File:Glycogen Branching Enzyme Scheme.tif|thumb|center|upright=2.5|Scheme demonstrating the function of glycogen branching enzyme]]
In [[glycogen]], every 10 to 14 [[glucose]] units, a side branch with an additional chain of glucose units occurs. The [[side chain]] attaches at carbon atom 6 of a glucose unit, an α-1,6-glycosidic bond. This connection is catalyzed by a branching enzyme, generally given the name α-glucan branching enzyme. A branching enzyme attaches a string of seven glucose units (with some minor variation to this number) to the carbon at the C-6 position on the glucose unit, forming the α-1,6-glycosidic bond. The specific nature of this enzyme means that this chain of 7 carbons is usually attached to a glucose molecule that is in position three from the [[Non-reducing sugar|non-reducing]] end of another chain. Because the enzyme works with such specificity regarding the number of glucose units transferred and the position to which they are transferred, the enzyme creates the very characteristic, highly branched glycogen molecule.<ref>{{cite book| vauthors = Rose S |title=The Chemistry of Life|year=1999|publisher=Pelican Books|pages=199–201}}</ref>

==Clinical significance==
Mutations in this gene are associated with [[glycogen storage disease type IV]] (also known as Andersen's disease) in newborns and with [[adult polyglucosan body disease]].<ref name="entrez"/><ref name=OMIM>{{cite web| vauthors = McKusick VA, Kniffin CL |title=OMIM Entry 263570 - Polyglucosan body neuropathy, adult form|url=https://omim.org/entry/263570|website=Online Mendelian Inheritance in Man|publisher=Johns Hopkins University|access-date=7 March 2017|language=en-us|date=May 2, 2016}}</ref>

Approximately 40 mutations in the GBE1 gene, most resulting in a point mutation in the glycogen branching enzyme, have led to the early childhood disorder, [[glycogen storage disease type IV]] (GSD IV).<ref name="Genetics Home Reference GBE1" />  This disease is characterized by a severe depletion or complete absence of GBE, resulting in the accumulation of abnormally structured glycogen, known as polyglucosan bodies.<ref name="Genetics Home Reference GBE1" />  Glycogen buildup leads to increased osmotic pressure resulting in cellular swelling and death.<ref name="Genetics Home Reference GBE1" />  The tissues most affected by this disease are the liver, heart, and neuromuscular system, areas with the greatest levels of glycogen accumulation.<ref name="Genetics Home Reference GBE1" /><ref>{{cite book| vauthors = Mingyi C | chapter = Glycogen Storages Diseases chapter of Molecular Pathology of Liver Diseases | veditors = Monga SP| title = Molecular Pathology of Liver Diseases |year=2011|publisher=Springer|pages=677–682| chapter-url=https://books.google.com/books?id=pO3SgjPkgCAC&q=glycogen+storage+diseases+mingyi+chen&pg=PR13 |isbn=9781441971074}}</ref>  Abnormal glycogen buildup in the liver interferes with liver functioning and can result in an enlarged liver and liver disease.<ref name="Genetics Home Reference GBE1" /><ref>{{cite journal | vauthors = Bruno C, van Diggelen OP, Cassandrini D, Gimpelev M, Giuffrè B, Donati MA, Introvini P, Alegria A, Assereto S, Morandi L, Mora M, Tonoli E, Mascelli S, Traverso M, Pasquini E, Bado M, Vilarinho L, van Noort G, Mosca F, DiMauro S, Zara F, Minetti C | title = Clinical and genetic heterogeneity of branching enzyme deficiency (glycogenosis type IV) | journal = Neurology | volume = 63 | issue = 6 | pages = 1053–1058 | date = September 2004 | pmid = 15452297 | doi = 10.1212/01.wnl.0000138429.11433.0d | s2cid = 7874969 | author-link20 = Salvatore DiMauro }}</ref>  In muscles, the inability of cells to efficiently breakdown glycogen due to the severe reduction or absence of branching can lead to muscle weakness and atrophy.<ref name="Genetics Home Reference GBE1" />  
At least three mutations in the GBE1 gene have been found to cause another disease called adult polyglucosan body disease (APBD).<ref name="Genetics Home Reference GBE1" /><ref name="APBD NCBI">{{cite book | vauthors = Klein C | chapter = Adult Polyglucosan Body Disease |chapter-url=https://www.ncbi.nlm.nih.gov/books/NBK5300/|publisher=University of Washington, Seattle|year=1993|pmid=20301758| title = GeneReviews}}</ref>  While in GSD IV GBE activity is undetectable or minimally detectable, APBD is characterized by reduced or even normal GBE activity.<ref name="APBD NCBI"/> In this disease, abnormal glycogen can build up in neurons leading to a spectrum of problems. Specifically, some disease characteristics are [[gait]] difficulties from mixed upper and lower motor neuron involvement sensory loss in lower extremities, and [[neurogenic bladder]], a problem in which a person lacks bladder control due to a brain, spinal cord, or nerve condition.<ref name="APBD NCBI"/><ref>{{cite journal | vauthors = Hussain A, Armistead J, Gushulak L, Kruck C, Pind S, Triggs-Raine B, Natowicz MR | title = The adult polyglucosan body disease mutation GBE1 c.1076A>C occurs at high frequency in persons of Ashkenazi Jewish background | journal = Biochemical and Biophysical Research Communications | volume = 426 | issue = 2 | pages = 286–288 | date = September 2012 | pmid = 22943850 | doi = 10.1016/j.bbrc.2012.08.089 }}</ref>

== References ==
{{Reflist|32em}}

== Further reading ==
{{refbegin|32em}}
* {{cite journal |vauthors=Barker SA, Bourne E, Peat S | title =  The enzymic synthesis and degradation of starch. Part IV. The purification and storage of the Q-enzyme of the potato| journal = Journal of the Chemical Society (Resumed)| volume = | pages = 1705&ndash;1711 | doi=10.1039/jr9490001705|year=1949 }}
* {{cite journal | vauthors = Baum H, Gilbert GA | title = A simple method for the preparation of crystalline potato phosphorylase and Q-enzyme | journal = Nature | volume = 171 | issue = 4361 | pages = 983–984 | date = May 1953 | pmid = 13063502 | doi = 10.1038/171983a0 | s2cid = 2243647 | bibcode = 1953Natur.171..983B }}
* {{cite book | vauthors = Hehre EJ | chapter = Enzymic Synthesis of Polysaccharides: A Biological type of Polymerization | year = 1951 | title = Advances in Enzymology - and Related Areas of Molecular Biology | journal = Advances in Enzymology and Related Subjects of Biochemistry | volume = 11 | pages = 297&ndash;337 | doi = 10.1002/9780470122563.ch6 | pmid = 24540594 | isbn = 978-0-470-12256-3 }}
* {{cite journal | vauthors = Allan CM, Wang Y, Jimenez M, Marshan B, Spaliviero J, Illingworth P, Handelsman DJ | title = Follicle-stimulating hormone increases primordial follicle reserve in mature female hypogonadal mice | journal = The Journal of Endocrinology | volume = 188 | issue = 3 | pages = 549–557 | date = March 2006 | pmid = 16522734 | doi = 10.1677/joe.1.06614 | doi-access = free }}
* {{cite journal | vauthors = Stelzl U, Worm U, Lalowski M, Haenig C, Brembeck FH, Goehler H, Stroedicke M, Zenkner M, Schoenherr A, Koeppen S, Timm J, Mintzlaff S, Abraham C, Bock N, Kietzmann S, Goedde A, Toksöz E, Droege A, Krobitsch S, Korn B, Birchmeier W, Lehrach H, Wanker EE | title = A human protein-protein interaction network: a resource for annotating the proteome | journal = Cell | volume = 122 | issue = 6 | pages = 957–968 | date = September 2005 | pmid = 16169070 | doi = 10.1016/j.cell.2005.08.029 | hdl-access = free | s2cid = 8235923 | hdl = 11858/00-001M-0000-0010-8592-0 }}
* {{cite journal | vauthors = Massa R, Bruno C, Martorana A, de Stefano N, van Diggelen OP, Federico A | title = Adult polyglucosan body disease: proton magnetic resonance spectroscopy of the brain and novel mutation in the GBE1 gene | journal = Muscle & Nerve | volume = 37 | issue = 4 | pages = 530–536 | date = April 2008 | pmid = 17994551 | doi = 10.1002/mus.20916 | s2cid = 18749059 }}
* {{cite journal | vauthors = Rose JE, Behm FM, Drgon T, Johnson C, Uhl GR | title = Personalized smoking cessation: interactions between nicotine dose, dependence and quit-success genotype score | journal = Molecular Medicine | volume = 16 | issue = 7–8 | pages = 247–253 | year = 2010 | pmid = 20379614 | pmc = 2896464 | doi = 10.2119/molmed.2009.00159 }}
* {{cite journal | vauthors = Hannula-Jouppi K, Kaminen-Ahola N, Taipale M, Eklund R, Nopola-Hemmi J, Kääriäinen H, Kere J | title = The axon guidance receptor gene ROBO1 is a candidate gene for developmental dyslexia | journal = PLOS Genetics | volume = 1 | issue = 4 | pages = e50 | date = October 2005 | pmid = 16254601 | pmc = 1270007 | doi = 10.1371/journal.pgen.0010050 | doi-access = free }}
* {{cite journal | vauthors = Konstantinidou AE, Anninos H, Dertinger S, Nonni A, Petersen M, Karadimas C, Havaki S, Marinos E, Akman HO, DiMauro S, Patsouris E | title = Placental involvement in glycogen storage disease type IV | journal = Placenta | volume = 29 | issue = 4 | pages = 378–381 | date = April 2008 | pmid = 18289670 | doi = 10.1016/j.placenta.2008.01.005 }}
* {{cite journal | vauthors = Melén E, Himes BE, Brehm JM, Boutaoui N, Klanderman BJ, Sylvia JS, Lasky-Su J | title = Analyses of shared genetic factors between asthma and obesity in children | journal = The Journal of Allergy and Clinical Immunology | volume = 126 | issue = 3 | pages = 631–7.e1–8 | date = September 2010 | pmid = 20816195 | pmc = 2941152 | doi = 10.1016/j.jaci.2010.06.030 }}
* {{cite journal | vauthors = Bruno C, van Diggelen OP, Cassandrini D, Gimpelev M, Giuffrè B, Donati MA, Introvini P, Alegria A, Assereto S, Morandi L, Mora M, Tonoli E, Mascelli S, Traverso M, Pasquini E, Bado M, Vilarinho L, van Noort G, Mosca F, DiMauro S, Zara F, Minetti C | title = Clinical and genetic heterogeneity of branching enzyme deficiency (glycogenosis type IV) | journal = Neurology | volume = 63 | issue = 6 | pages = 1053–1058 | date = September 2004 | pmid = 15452297 | doi = 10.1212/01.wnl.0000138429.11433.0d | s2cid = 7874969 }}
* {{cite journal | vauthors = Ziemssen F, Sindern E, Schröder JM, Shin YS, Zange J, Kilimann MW, Malin JP, Vorgerd M | title = Novel missense mutations in the glycogen-branching enzyme gene in adult polyglucosan body disease | journal = Annals of Neurology | volume = 47 | issue = 4 | pages = 536–540 | date = April 2000 | pmid = 10762170 | doi = 10.1002/1531-8249(200004)47:4<536::AID-ANA22>3.0.CO;2-K | s2cid = 42856760 }}
* {{cite journal | vauthors = McCarthy JJ, Meyer J, Moliterno DJ, Newby LK, Rogers WJ, Topol EJ | title = Evidence for substantial effect modification by gender in a large-scale genetic association study of the metabolic syndrome among coronary heart disease patients | journal = Human Genetics | volume = 114 | issue = 1 | pages = 87–98 | date = December 2003 | pmid = 14557872 | doi = 10.1007/s00439-003-1026-1 | s2cid = 2568593 }}
* {{cite journal | vauthors = Tay SK, Akman HO, Chung WK, Pike MG, Muntoni F, Hays AP, Shanske S, Valberg SJ, Mickelson JR, Tanji K, DiMauro S | title = Fatal infantile neuromuscular presentation of glycogen storage disease type IV | journal = Neuromuscular Disorders | volume = 14 | issue = 4 | pages = 253–260 | date = April 2004 | pmid = 15019703 | doi = 10.1016/j.nmd.2003.12.006 | s2cid = 34056349 }}
* {{cite journal | vauthors = Pescador N, Villar D, Cifuentes D, Garcia-Rocha M, Ortiz-Barahona A, Vazquez S, Ordoñez A, Cuevas Y, Saez-Morales D, Garcia-Bermejo ML, Landazuri MO, Guinovart J, del Peso L | title = Hypoxia promotes glycogen accumulation through hypoxia inducible factor (HIF)-mediated induction of glycogen synthase 1 | journal = PLOS ONE | volume = 5 | issue = 3 | pages = e9644 | date = March 2010 | pmid = 20300197 | pmc = 2837373 | doi = 10.1371/journal.pone.0009644 | doi-access = free | bibcode = 2010PLoSO...5.9644P }}
* {{cite journal | vauthors = Bruno C, Cassandrini D, Assereto S, Akman HO, Minetti C, Di Mauro S | title = Neuromuscular forms of glycogen branching enzyme deficiency | journal = Acta Myologica | volume = 26 | issue = 1 | pages = 75–78 | date = July 2007 | pmid = 17915577 | pmc = 2949312 }}
* {{cite journal | vauthors = Flachsbart F, Franke A, Kleindorp R, Caliebe A, Blanché H, Schreiber S, Nebel A | title = Investigation of genetic susceptibility factors for human longevity - a targeted nonsynonymous SNP study | journal = Mutation Research | volume = 694 | issue = 1–2 | pages = 13–19 | date = December 2010 | pmid = 20800603 | doi = 10.1016/j.mrfmmm.2010.08.006 | bibcode = 2010MRFMM.694...13F }}
* {{cite journal | vauthors = Rush J, Moritz A, Lee KA, Guo A, Goss VL, Spek EJ, Zhang H, Zha XM, Polakiewicz RD, Comb MJ | title = Immunoaffinity profiling of tyrosine phosphorylation in cancer cells | journal = Nature Biotechnology | volume = 23 | issue = 1 | pages = 94–101 | date = January 2005 | pmid = 15592455 | doi = 10.1038/nbt1046 | s2cid = 7200157 }}
* {{cite journal | vauthors = Bailey SD, Xie C, Do R, Montpetit A, Diaz R, Mohan V, Keavney B, Yusuf S, Gerstein HC, Engert JC, Anand S | title = Variation at the NFATC2 locus increases the risk of thiazolidinedione-induced edema in the Diabetes REduction Assessment with ramipril and rosiglitazone Medication (DREAM) study | journal = Diabetes Care | volume = 33 | issue = 10 | pages = 2250–2253 | date = October 2010 | pmid = 20628086 | pmc = 2945168 | doi = 10.2337/dc10-0452 }}
{{refend}}

== External links ==
{{Commons category}}
{{Portal|Biology}}
*[https://www.ncbi.nlm.nih.gov/books/NBK5300/  GeneReviews/NCBI/NIH/UW entry on Adult Polyglucosan Body Disease]
*[https://www.ncbi.nlm.nih.gov/omim/232500,263570,607839,263570,607839  OMIM entries on Adult Polyglucosan Body Disease]
* {{PDBe-KB2|Q04446|1,4-alpha-glucan-branching enzyme}}

{{Glycogenesis and glycogenolysis}}
{{Glycosyltransferases}}
{{Enzymes}}

[[Category:Carbohydrate metabolism]]
[[Category:EC 2.4.1]]
[[Category:Genes mutated in mice]]
[[Category:Enzymes of known structure]]
[[Category:Enzymes]]
[[Category:Transferases]]