Cataracts of varied etiologis, including heriditary cataracts, are associated with altered levels of gamma-crystallins. We now have succeeded in cloning different gamma-crystallin cDNA sequences and we have determined the complete nucleotide sequence of a bovine gamma-crystallin mRNA. Gamma-crystallins are characteristically synthesised in the terminally differentiating lens fibre cells and therefore, can be used as convenient markers of differential gene expression. The present study will attempt to elucidate the molecular genetic mechanisms involved in the development and regulation of the spatially and temporally controlled heterogeneity of gamma-crystallins in the calf and the human lens, during normal differentiation and diseased states. Toward this goal, using the cloned probes already available in our laboratory, we will isolate the major human gamma-crystallin gene(s) and characterize them by complete sequence analyses. Using recombinant DNA techniques, DNA sequences will be deleted from or added to the isolated human and/or bovine gene(s). The expression of these genes will be monitored in cell-free systems and in vivo, by microinjecting them into the nuclei of the lesn epithelial cells, maintained in primary cultures (gamma-crystallins are not synthesised in these cells). Transcriptional regulation in the differentiated lens fibres and epithelial cells will be investigated both in vitro and in vivo by studying the processing of the nuclear transcripts of the gamma-crystallin mRNA. Utilizing restriction enzymes and specific human and bovine cloned DNA probes, we will attempt to map sequence polymorphisms, mutations or defects in the gamma-crystallin gene sequences of the individuals suspected of having cataracts of genetic origin. This study will investigate the possible involvement of the regulation of gene expression in the maintenance of ocular transparency and in the development of cataractous lenses.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY006044-02
Application #
3261964
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1985-01-01
Project End
1989-04-30
Budget Start
1985-05-01
Budget End
1986-04-30
Support Year
2
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of California Los Angeles
Department
Type
Schools of Medicine
DUNS #
119132785
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
Jing, Zhe; Gangalum, Rajendra K; Bhat, Ankur M et al. (2014) HSF4 mutation p.Arg116His found in age-related cataracts and in normal populations produces childhood lamellar cataract in transgenic mice. Hum Mutat 35:1068-71
Jing, Zhe; Gangalum, Rajendra K; Mock, Dennis C et al. (2014) A gene-specific non-enhancer sequence is critical for expression from the promoter of the small heat shock protein gene ?B-crystallin. Hum Genomics 8:5
Gangalum, Rajendra K; Jing, Zhe; Bhat, Ankur M et al. (2014) Expression of the HSF4 DNA binding domain-EGFP hybrid gene recreates early childhood lamellar cataract in transgenic mice. Invest Ophthalmol Vis Sci 55:7227-40
Gangalum, Rajendra K; Horwitz, Joseph; Kohan, Sirus A et al. (2012) ?A-crystallin and ?B-crystallin reside in separate subcellular compartments in the developing ocular lens. J Biol Chem 287:42407-16
Rao, Narsing A; Saraswathy, Sindhu; Pararajasegaram, Geeta et al. (2012) Small heat shock protein ýýA-crystallin prevents photoreceptor degeneration in experimental autoimmune uveitis. PLoS One 7:e33582
Gangalum, Rajendra K; Bhat, Suraj P (2009) AlphaB-crystallin: a Golgi-associated membrane protein in the developing ocular lens. Invest Ophthalmol Vis Sci 50:3283-90
Nagineni, C N; Bhat, S P (1992) Lens fiber cell differentiation and expression of crystallins in co-cultures of human fetal lens epithelial cells and fibroblasts. Exp Eye Res 54:193-200
Porrello, K; Bhat, S P; Bok, D (1991) Detection of interphotoreceptor retinoid binding protein (IRBP) mRNA in human and cone-dominant squirrel retinas by in situ hybridization. J Histochem Cytochem 39:171-6
Bhat, S P (1990) Synthesis of nucleic acid probes on membrane supports: a procedure for the removal of unincorporated precursors. Anal Biochem 184:59-62
Nagineni, C N; Bhat, S P (1989) Alpha B-crystallin is expressed in kidney epithelial cell lines and not in fibroblasts. FEBS Lett 249:89-94

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