Lengsin is a survivor of an ancient family of class I glutamine synthetases re-engineered by evolution for a role in the vertebrate lens.
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ABSTRACT:
SUBMITTER: Wyatt K
PROVIDER: S-EPMC1868402 | biostudies-literature | 2006 Dec
REPOSITORIES: biostudies-literature
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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 Keith K White Helen E HE Wang Luchun L Bateman Orval A OA Slingsby Christine C Orlova Elena V EV Wistow Graeme G
Structure (London, England : 1993) 20061201 12
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 ...[more]
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