Oxyopia Abstract

October 13, 2006
Friday, 4 PM
489 Minor Hall

Joseph Horwitz, PhD
Professor, Jules Stein Eye Institute
Host: Xiaohua Gong

Title

Structure and Function of alpha-crystallin

Abstract

In the last decade alpha-crystallin, a major protein component of the vertebrate eye lens has been the subject of intense investigations into its structure andfunction. Being a key member of the small heat-shock proteins, the "alphacrystallin domain" is a consensus sequence that is common to all the members of the small heat-shock protein super family. There are two alpha-crystallingenes, alpha A and alpha B. In the mammalian lens, the molar ratio of alpha Ato alpha B is generally three to one. In humans, the alpha A genes is found on chromosome 21 and encodes for a 173 amino acid residue protein, while the alpha B gene is found on chromosome 11 encoding for 175 amino acid residue protein. The amino acid sequence homology between alpha A and alpha B is about 57%. Alpha A-crystallin is found mainly in the lens with trace amounts in other tissues. Alpha B-crystallin is essentially considered to be a ubiquitous protein. Alpha B-crystallin is found to be over-expressed in many neurological diseases, and mutations in alpha A or B-crystallin can cause cataract and myopathy.

[Back to Horwitz - Oxyopia Page]