Class III POU genes: Generation of homopolymeric amino acid repeats under GC pressure in mammals
- 73 Downloads
The class III POU transcription factor genes play an important role in the nervous system. Comparison of their entire amino acid sequences disclosed a remarkable feature of particular mammalian class III POU genes. Alanine, glycine, and proline repeats were present in the mammalian Brain-1 gene, whereas most of these repeats were absent in the nonmammalian homologue. The mammalian Brain-2 gene had alanine, glycine, proline, and glutamine repeats, which were missing in the nonmammalian homologue. The mammalian Scip gene had alanine, glycine, proline, and histidine repeats, but the nonmammalian homologue completely lacked these repeats. In contrast, the mammalian Brain-4 gene had no amino acid repeats like its nonmammalian homologue. The mammalian genes containing the characteristic amino acid repeats had another feature, higher GC content. We found a positive correlation between the GC content and the amino acid repeat ratio. Those amino acids were encoded by triplet codons with relatively high GC content. These results suggest that the GC pressure has facilitated generation of the homopolymeric amino acid repeats.
Key wordsPOU Human Brain-1 GC pressure Amino acid repeats
Unable to display preview. Download preview PDF.
- Duboule D (1994) Guidebook to the homeobox genes. Sambrook and Tooze Publication at Oxford University Press, OxfordGoogle Scholar
- Huber I, Bitner-Glindzicz M, De Kok YJM, Van der Maarel SM, Ishikawa-Brush Y, Monaco AP, Robinson D, Maocolm S, Pembrey ME, Brunner HG, Cremers FPM, Ropers H (1994) X-linked mixed deafness (DFN3): cloning and characterization of the critical region allows the identification of novel microdeletions. Hum Mol Genet 3:1151–1154PubMedGoogle Scholar
- Orii H, Agata K, Watanabe K (1993) POU domain genes in planarianDugesia japonica: the structure and expression. Biochem Biophys Res Common 192:1395–1402Google Scholar
- Sambrook TH, Fritsche EF, Maniatis T (1989) Molecular cloning: a Laboratory Manual. 2nd ed. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NYGoogle Scholar
- Verrijizer CP, Van der Vliet PC (1993) POU domain transcription factors. Biochim Biophys Acta 1173:1–21Google Scholar