These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Structure and expression of the scallop Omega-crystallin gene. Evidence for convergent evolution of promoter sequences.
    Author: Carosa E, Kozmik Z, Rall JE, Piatigorsky J.
    Journal: J Biol Chem; 2002 Jan 04; 277(1):656-64. PubMed ID: 11682475.
    Abstract:
    Omega-crystallin of the scallop lens is an inactive aldehyde dehydrogenase (1A9). Here we have cloned the scallop Omega-crystallin gene. Except for an extra novel first exon, its 14-exon structure agrees well with that of mammalian aldehyde dehydrogenases 1, 2, and 6. The -2120/+63, -714/+63, and -156/+63 Omega-crystallin promoter fragments drive the luciferase reporter gene in transfected alphaTN4-1 lens cells and L929 fibroblasts but not in Cos7 cells. Putative binding sequences for cAMP-responsive element-binding protein (CREB)/Jun, alphaACRYBP1, AP-1, and PAX-6 in the Omega-crystallin promoter are surprisingly similar to the cis-elements used for lens promoter activity of the mouse and chicken alphaA-crystallin genes, which encode proteins homologous to small heat shock proteins. Site-specific mutations in the overlapping CREB/Jun and Pax-6 sites abolished activity of the Omega-crystallin promoter in transfected cells. Gel shift experiments utilizing extracts from the alphaTN4-1, L929, and Cos7 cells and the scallop stomach and oligonucleotides derived from the putative binding sites of the Omega-crystallin promoter showed complex formation. Gel shift experiments showed binding of recombinant Pax-6 and CREB to their respective sites. Our data suggest convergent evolutionary adaptations that underlie the preferential expression of crystallin genes in the lens of vertebrates and invertebrates.
    [Abstract] [Full Text] [Related] [New Search]