Molecular cloning, developmental expression, and hormonal regulation of zebrafish (Danio rerio) β crystallin B1, a member of the superfamily of β crystallin proteins
Journal
Biochemical and Biophysical Research Communications
Journal Volume
285
Journal Issue
1
Pages
343-349
Date Issued
2001
Author(s)
Abstract
The cDNA sequence of β crystallin B1 was determined from zebrafish (Danio rerio) and compared to the corresponding genes of bovine, rat, chicken, human, and Xenopus. Multispecies comparison of superfamily diversity demonstrated β crystallin B1 homology between zebrafish, bovine, chicken, and rat, but large distances to β crystallin B2 and B3. Zebrafish cDNA has a size of 943 nucleotides and encodes a polypeptide of 233 amino acids. Zebrafish β crystallin B1 shares 71.30, 75.86, and 71.00% similarities with bovine, chicken, and rat β crystallin B1, respectively, Northern blot analysis revealed a single 0.9-kb β crystallin B1 transcript which was expressed and progressively increased in the first 20 h of zebrafish embryogenesis. Whole-mount in situ hybridization revealed that the β crystallin B1 transcript was only specifically expressed in the lens region of the eye. A starvation experiment revealed no variation in mRNA levels after 14 and 21 days. An experiment in which hormone was injected showed that the β crystallin B1 transcript first increased 24 h after the injection of insulin-like growth factor I, insulin-like growth factor II, or growth hormone, then decreased 48 h after injection. The β crystallin B1 transcript continuously increased after insulin was injected. Taken together, our results identify the early specific expression of β crystallin B1 within the lens. Despite small differences, these results indicate that both the structure of the β crystallin B1 protein and its involvement with regulation by growth factors appear to have been remarkably conserved. © 2001 Academic Press.
Publisher
Academic Press Inc.
Type
journal article