The mechanism of sex-specific splicing at the doublesex gene is different between Drosophila melanogaster and Bombyx mori
The mechanism of sex-specific splicing at the doublesex gene is different between Drosophila melanogaster and Bombyx mori
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DOI：
10.1016/s0965-1748(01)00067-4
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发表时间：
2001-11-01
影响因子：
3.8
通讯作者：
Shimada, T
中科院分区：
文献类型：
--
作者：
Suzuki, MG;Ohbayashi, F;Shimada, T
我们以前曾报道，Bmdsx，同源性的性别决定基因，doublex（dsx），被发现是性别特异性表达在各种组织中的幼虫，蛹，和成人阶段的家蚕，家蚕，并选择性剪接产生男性和女性特异性的mRNA。为了揭示Bmdsx前mRNA剪接模式的性别特异性差异，测定基因组序列并与男性和女性特异性Bmdsx cDNA序列进行比较。开放阅读框（ORF）由5个外显子组成。外显子3和4被特异性地掺入雌性型Bmdsx mRNA中。另一方面，外显子2剪接到外显子5以产生Bmdsx的雄性型mRNA。在果蝇dsx的情况下，OD 2结构域被分隔成性别独立和性别依赖区域的女性特异性内含子。性别特异性剪接发生在果蝇dsx基因的相同位置。然而，与果蝇dsx不同的是，雌性特异性内含子没有显示出弱的3'剪接位点，并且在雌性特异性外显子中没有发现TRA/TRA-2结合位点相关序列，甚至在Bmdsx基因的任何其他区域中也没有发现。此外，在体外剪接反应组成的HeLa细胞核提取物表明，女性型的Bmdsx mRNA代表默认剪接。这些是：结果表明，Bmdsx前体mRNA的性别特异性剪接模式的结构特征与果蝇dsx的相似，但Bmdsx前体mRNA的性别特异性选择性剪接的调控不同。(C)2001爱思唯尔科技有限公司版权所有。
We have previously reported that Bmdsx, a homologue of the sex-determining gene, doublesex (dsx), was found to be sex-specifically expressed in various tissues at larval, pupal, and adult stages in the silkworm, Bombyx mori, and was alternatively spliced to yield male- and female-specific mRNAs. To reveal sex-specific differences in splicing patterns of Bmdsx pre-mRNA, the genomic sequence was determined and compared with male- and female-specific Bmdsx cDNA sequences. The open reading frame (ORF) consisted of five exons. Exons 3 and 4 were specifically incorporated into the female type of Bmdsx mRNA. On the other hand, exon 2 was spliced to exon 5 to produce the male type mRNA of Bmdsx. As in the case of Drosophila dsx, the OD2 domain was separated by a female-specific intron into sex-independent and sex-dependent regions. Sex-specific splicing occurred in equivalent positions in the Drosophila dsx gene. However, unlike Drosophila dsx, the female-specific introns showed no weak 3' splice sites, and the TRA/TRA-2 binding site related sequences were not found in the female-specific exon, nor even in any other regions of the Bmdsx gene. Moreover, an in vitro splicing reaction consisting of HeLa cell nuclear extracts showed that the female-type of Bmdsx mRNA represented the default splicing. These: findings suggest that the structural features of the sex-specific splicing patterns of Bmdsx pre-mRNA are similar to those of Drosophila dsx but the regulation of sex-specific alternative splicing of Bmdsx pre-mRNA is different. (C) 2001 Elsevier Science Ltd. All rights reserved.