Computer construction and analysis of protein models of the mutant gammaD-crystallin gene.
BACKGROUND
Gammad-crystallin plays an important role in human cataract formation. Being highly stable, gammaD-crystallin proteins are composed of two domains. In this study we constructed and analyzed protein models of the mutant gammaD-crystallin gene, which caused a special fasciculiform congenital cataract affecting a large Chinese family.


METHODS
gammaD-crystallin protein structure was predicted by Swiss-Model software using bovine gammaD-crystallin as a template and Prospect software using human betab2-crystallin as a template. The models were observed with a Swiss-Pdb viewer.


RESULTS
The mutant gammaD-crystallin structure predicted by the Swiss-Model software showed that proline23 was an exposed surface residue and P23T change made a decreased hydrogen bond distance between threonine23 and asparagine49. The mutant gammaD-crystallin structure predicted by the Prospect software showed that the P23T change exerted a significant effect on the protein's tertiary structure and yielded hydrogen bonds with aspartic acid21, asparagine24, asparagine49 and serine74.


CONCLUSIONS
The mutant gammaD-crystallin gene has a significant effect on the protein's tertiary structure, supporting that alteration of gamma-crystallin plays an important role in human cataract formation.
Yao
Ke
K
Eye Center, Affiliated Second Hospital, Zhejiang University School of Medicine, Hangzhou 310009, China. xlren@zju.edu.cn
Sun
Zhao-hui
ZH
Shentu
Xing-chao
XC
Wang
Kai-jun
KJ
Tan
Jian
J
D000818:Animals; D002417:Cattle; D003198:Computer Simulation; D006860:Hydrogen Bonding; D008958:Models, Molecular; D009154:Mutation; D017434:Protein Structure, Tertiary; D038222:gamma-Crystallins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology
D038222:gamma-Crystallins