2j9i
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="2j9i" size="350" color="white" frame="true" align="right" spinBox="true" caption="2j9i" /> '''LENGSIN IS A SURVIVOR OF AN ANCIENT FAMILY O...)
Next diff →
Revision as of 18:52, 29 January 2008
|
LENGSIN IS A SURVIVOR OF AN ANCIENT FAMILY OF CLASS I GLUTAMINE SYNTHETASES IN EUKARYOTES THAT HAS UNDERGONE EVOLUTIONARY RE-ENGINEERING FOR A TISSUE-SPECIFIC ROLE IN THE VERTEBRATE EYE LENS.
Overview
Lengsin is a major protein of the vertebrate eye lens. It belongs to the, hitherto purely prokaryotic GS I branch of the glutamine synthetase (GS), superfamily, but has no enzyme activity. Like the taxon-specific, crystallins, Lengsin is the result of the recruitment of an ancient enzyme, to a noncatalytic role in the vertebrate lens. Cryo-EM and modeling, studies of Lengsin show a dodecamer structure with important similarities, and differences with prokaryotic GS I structures. GS homology regions of, Lengsin are well conserved, but the N-terminal domain shows evidence of, dynamic evolutionary changes. Compared with birds and fish, most mammals, have an additional exon corresponding to part of the N-terminal domain;, however, in human, this is a nonfunctional pseudoexon. Genes related to, Lengsin are also present in the sea urchin, suggesting that this branch of, the GS I family, supplanted by GS II enzymes in vertebrates, has an, ancient role in metazoans.
About this Structure
2J9I is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
Lengsin is a survivor of an ancient family of class I glutamine synthetases re-engineered by evolution for a role in the vertebrate lens., Wyatt K, White HE, Wang L, Bateman OA, Slingsby C, Orlova EV, Wistow G, Structure. 2006 Dec;14(12):1823-34. PMID:17161372
Page seeded by OCA on Tue Jan 29 20:52:02 2008
