International Mammalian Genome Society

The 16th International Mouse Genome Conference (2002)


POSTER 145 - THE INDENTIFICATION OF MUTATIONS OF THE LENS GAP JUNCTION PROTEIN Gja3 LEADING TO CATARACT IN THE MOUSE

J Favor
GSF

2) Gong X, 1) Neuhäuser-Klaus A, 1) Pretsch W, 1) Sandulache R
1) GSF, 2) Scripps Research Institute

Cell-cell communication in the avascular lens is essential for the exchange of ions, metabolites and small cell signaling molecules among the epithelial and lens fiber cells. Disruption of the normal physiological state could lead to cataract. Gap-junctional channels play an important role in lens intercellular communication. Three gap junction proteins (Gja1, Gja3, Gja8) are expressed in the lens and are the subunits of gap junction formation. It follows that mutations in the corresponding genes are likely associated with eye abnormalities. In the analysis of our collection of dominant eye mutations in the mouse, 3 have been mapped to chromosome 14 in the vicinity of Gja3. Heterozygotes of all three mutations result in cataract (nuclear, sub-cortical or total). To date two have been molecularly confirmed as mutant alleles of Gja3. Together with our results for Gja8, the present results indicate the physiological importance of these two genes for lens development/function. In contrast, we have not yet identified a mutation of the Gja1 gene. A number of explanations are possible including chance, a low inherent locus mutability or haplo-sufficiency. Gap junction formation entails a number of steps including protein expression, oligomerization in the cell, membrane incorporation and hemichannel docking of adjoining cells. Different domains of the gap junction proteins are important for specific steps. The generation of allelic series at these and other loci, especially point mutations following chemical mutagenesis, will be important in analysing the function of the respective genes and gene domains.Research supported in part by NIH grant R01EY10321.


Abstracts * Officers * Bylaws * Application Form * Meeting Calendar * Contact Information * Home * Resources * News and Views * Membership

Base url http://imgs.org
Last modified: Saturday, November 3, 2012