Nayler O, Cap C, Stamm S
Max-Planck Institute of Neurobiology, Max-Planck Institute of Biochemistry, Am Klopferspitz 18a, Martinsried, D-82152, Germany.
Genomics. 1998 Oct 15;53(2):191-202. doi: 10.1006/geno.1998.5471.
Htra2-beta is a human homologue of Drosophila transformer-2 and a member of the SR-like protein family. Here we report the isolation and characterization of the complete htra2-beta gene (HGMW-approved symbol SFRS10). The gene spans 21,232 bp and is composed of 10 exons and 9 introns. Radiation hybrid mapping localized the gene to chromosome 3q. The region upstream of the transcription initiation codon contains an Alu element and several potential transcription factor binding sites. RT-PCR and comparison with EST clones revealed five different RNA isoforms generated by alternative splicing. These isoforms encode three diverging open reading frames, and two of these, htra2-beta3 and htra2-beta4, lack the first SR domain. Htra2-beta3 is developmentally regulated and expressed predominantly in brain, liver testis, and weakly in kidney. Furthermore, the domain structure of htra2-beta3 resembles a variant found in the Drosophila male germline, indicating a remarkable conservation of alternative transformer-2 variants. Finally, we show that htra2-beta3 is expressed in the nucleus and interacts with a subset of SR proteins in a yeast two-hybrid system and in vivo.
Htra2-β是果蝇transformer-2的人类同源物，也是SR样蛋白家族的成员。在此，我们报告完整htra2-β基因（HGMW批准符号为SFRS10）的分离和特征。该基因跨度为21,232 bp，由10个外显子和9个内含子组成。辐射杂种图谱将该基因定位到3号染色体q区。转录起始密码子上游区域包含一个Alu元件和几个潜在的转录因子结合位点。RT-PCR及与EST克隆的比较揭示了通过可变剪接产生的五种不同RNA异构体。这些异构体编码三个不同的开放阅读框，其中两个，htra2-β3和htra2-β4，缺少第一个SR结构域。Htra2-β3受发育调控，主要在脑、肝、睾丸中表达，在肾中表达较弱。此外，htra2-β3的结构域结构类似于果蝇雄性生殖系中发现的一种变体，表明transformer-2可变体具有显著的保守性。最后，我们表明htra2-β3在细胞核中表达，并在酵母双杂交系统和体内与一部分SR蛋白相互作用。
