7zay

From Proteopedia

(Difference between revisions)

Current revision

Human heparan sulfate polymerase complex EXT1-EXT2

Structural highlights

7zay is a 2 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	Electron Microscopy, Resolution 2.8Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Disease

EXT1_HUMAN Trichorhinophalangeal syndrome type 2;Chondrosarcoma;Multiple osteochondromas. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry.

Function

EXT1_HUMAN Glycosyltransferase forming with EXT2 the heterodimeric heparan sulfate polymerase which catalyzes the elongation of the heparan sulfate glycan backbone (PubMed:10639137, PubMed:22660413, PubMed:36402845, PubMed:36593275, PubMed:9620772). Glycan backbone extension consists in the alternating transfer of (1->4)-beta-D-GlcA and (1->4)-alpha-D-GlcNAc residues from their respective UDP-sugar donors. Both EXT1 and EXT2 are required for the full activity of the polymerase since EXT1 bears the N-acetylglucosaminyl-proteoglycan 4-beta-glucuronosyltransferase activity within the complex while EXT2 carries the glucuronosyl-N-acetylglucosaminyl-proteoglycan 4-alpha-N-acetylglucosaminyltransferase activity (PubMed:36402845, PubMed:36593275). Heparan sulfate proteoglycans are ubiquitous components of the extracellular matrix and play an important role in tissue homeostasis and signaling (PubMed:10639137, PubMed:11391482, PubMed:22660413, PubMed:9620772).^[1] ^[2] ^[3] ^[4] ^[5] ^[6]

Publication Abstract from PubMed

Heparan sulfates are complex polysaccharides that mediate the interaction with a broad range of protein ligands at the cell surface. A key step in heparan sulfate biosynthesis is catalyzed by the bi-functional glycosyltransferases EXT1 and EXT2, which generate the glycan backbone consisting of repeating N-acetylglucosamine and glucuronic acid units. The molecular mechanism of heparan sulfate chain polymerization remains, however, unknown. Here, we present the cryo-electron microscopy structure of human EXT1-EXT2, which reveals the formation of a tightly packed hetero-dimeric complex harboring four glycosyltransferase domains. A combination of in vitro and in cellulo mutational studies is used to dissect the functional role of the four catalytic sites. While EXT1 can catalyze both glycosyltransferase reactions, our results indicate that EXT2 might only have N-acetylglucosamine transferase activity. Our findings provide mechanistic insight into heparan sulfate chain elongation as a nonprocessive process and lay the foundation for future studies on EXT1-EXT2 function in health and disease.

Structure of the human heparan sulfate polymerase complex EXT1-EXT2.,Leisico F, Omeiri J, Le Narvor C, Beaudouin J, Hons M, Fenel D, Schoehn G, Coute Y, Bonnaffe D, Sadir R, Lortat-Jacob H, Wild R Nat Commun. 2022 Nov 19;13(1):7110. doi: 10.1038/s41467-022-34882-6. PMID:36402845^[7]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ McCormick C, Duncan G, Goutsos KT, Tufaro F. The putative tumor suppressors EXT1 and EXT2 form a stable complex that accumulates in the Golgi apparatus and catalyzes the synthesis of heparan sulfate. Proc Natl Acad Sci U S A. 2000 Jan 18;97(2):668-73. PMID:10639137 doi:10.1073/pnas.97.2.668
↑ Cheung PK, McCormick C, Crawford BE, Esko JD, Tufaro F, Duncan G. Etiological point mutations in the hereditary multiple exostoses gene EXT1: a functional analysis of heparan sulfate polymerase activity. Am J Hum Genet. 2001 Jul;69(1):55-66. PMID:11391482 doi:10.1086/321278
↑ Baietti MF, Zhang Z, Mortier E, Melchior A, Degeest G, Geeraerts A, Ivarsson Y, Depoortere F, Coomans C, Vermeiren E, Zimmermann P, David G. Syndecan-syntenin-ALIX regulates the biogenesis of exosomes. Nat Cell Biol. 2012 Jun 3;14(7):677-85. doi: 10.1038/ncb2502. PMID:22660413 doi:http://dx.doi.org/10.1038/ncb2502
↑ Leisico F, Omeiri J, Le Narvor C, Beaudouin J, Hons M, Fenel D, Schoehn G, Coute Y, Bonnaffe D, Sadir R, Lortat-Jacob H, Wild R. Structure of the human heparan sulfate polymerase complex EXT1-EXT2. Nat Commun. 2022 Nov 19;13(1):7110. doi: 10.1038/s41467-022-34882-6. PMID:36402845 doi:http://dx.doi.org/10.1038/s41467-022-34882-6
↑ Li H, Chapla D, Amos RA, Ramiah A, Moremen KW, Li H. Structural basis for heparan sulfate co-polymerase action by the EXT1-2 complex. Nat Chem Biol. 2023 May;19(5):565-574. PMID:36593275 doi:10.1038/s41589-022-01220-2
↑ McCormick C, Leduc Y, Martindale D, Mattison K, Esford LE, Dyer AP, Tufaro F. The putative tumour suppressor EXT1 alters the expression of cell-surface heparan sulfate. Nat Genet. 1998 Jun;19(2):158-61. PMID:9620772 doi:10.1038/514
↑ Leisico F, Omeiri J, Le Narvor C, Beaudouin J, Hons M, Fenel D, Schoehn G, Coute Y, Bonnaffe D, Sadir R, Lortat-Jacob H, Wild R. Structure of the human heparan sulfate polymerase complex EXT1-EXT2. Nat Commun. 2022 Nov 19;13(1):7110. doi: 10.1038/s41467-022-34882-6. PMID:36402845 doi:http://dx.doi.org/10.1038/s41467-022-34882-6

1 Structural highlights
2 Disease
3 Function
4 Publication Abstract from PubMed
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/7zay"

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[7zay]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7ZAY OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7ZAY FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=UDP:URIDINE-5-DIPHOSPHATE'>UDP</scene></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 2.8&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BMA:BETA-D-MANNOSE'>BMA</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=UDP:URIDINE-5-DIPHOSPHATE'>UDP</scene></td></tr>
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=7zay FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7zay OCA], [https://pdbe.org/7zay PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7zay RCSB], [https://www.ebi.ac.uk/pdbsum/7zay PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7zay ProSAT]</span></td></tr>
 </table>
 == Disease ==
-[https://www.uniprot.org/uniprot/EXT1_HUMAN EXT1_HUMAN] Chondrosarcoma;Multiple osteochondromas;Trichorhinophalangeal syndrome type 2. The disease is caused by variants affecting the gene represented in this entry.  The gene represented in this entry is involved in disease pathogenesis. A chromosomal aberration resulting in the loss of functional copies of TRPS1 and EXT1 has been found in TRPS2 patients.  The disease is caused by variants affecting the gene represented in this entry.
+[https://www.uniprot.org/uniprot/EXT1_HUMAN EXT1_HUMAN] Trichorhinophalangeal syndrome type 2;Chondrosarcoma;Multiple osteochondromas. The disease is caused by variants affecting the gene represented in this entry.  The disease is caused by variants affecting the gene represented in this entry.
 == Function ==
-[https://www.uniprot.org/uniprot/EXT1_HUMAN EXT1_HUMAN] Glycosyltransferase required for the biosynthesis of heparan-sulfate. The EXT1/EXT2 complex possesses substantially higher glycosyltransferase activity than EXT1 or EXT2 alone. Appears to be a tumor suppressor. Required for the exosomal release of SDCBP, CD63 and syndecan (PubMed:22660413).<ref>PMID:11518722</ref> <ref>PMID:22660413</ref>
+[https://www.uniprot.org/uniprot/EXT1_HUMAN EXT1_HUMAN] Glycosyltransferase forming with EXT2 the heterodimeric heparan sulfate polymerase which catalyzes the elongation of the heparan sulfate glycan backbone (PubMed:10639137, PubMed:22660413, PubMed:36402845, PubMed:36593275, PubMed:9620772). Glycan backbone extension consists in the alternating transfer of (1->4)-beta-D-GlcA and (1->4)-alpha-D-GlcNAc residues from their respective UDP-sugar donors. Both EXT1 and EXT2 are required for the full activity of the polymerase since EXT1 bears the N-acetylglucosaminyl-proteoglycan 4-beta-glucuronosyltransferase activity within the complex while EXT2 carries the glucuronosyl-N-acetylglucosaminyl-proteoglycan 4-alpha-N-acetylglucosaminyltransferase activity (PubMed:36402845, PubMed:36593275). Heparan sulfate proteoglycans are ubiquitous components of the extracellular matrix and play an important role in tissue homeostasis and signaling (PubMed:10639137, PubMed:11391482, PubMed:22660413, PubMed:9620772).<ref>PMID:10639137</ref> <ref>PMID:11391482</ref> <ref>PMID:22660413</ref> <ref>PMID:36402845</ref> <ref>PMID:36593275</ref> <ref>PMID:9620772</ref>
 <div style="background-color:#fffaf0;">
 == Publication Abstract from PubMed ==

7zay

From Proteopedia

Current revision

Human heparan sulfate polymerase complex EXT1-EXT2

Structural highlights

Disease

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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