Tandem 41-bp repeats in chicken and Japanese quail genomes: FISH mapping and transcription analysis on lampbrush chromosomes
Tandem 41-bp repeats in chicken and Japanese quail genomes: FISH mapping and transcription analysis on lampbrush chromosomes
复制标题
DOI：
10.1007/s00412-007-0117-5
复制
发表时间：
2007-12-01
期刊：
影响因子：
1.6
通讯作者：
Gaginskaya, Elena
中科院分区：
文献类型：
--
作者：
Deryusheva, Svetlana;Krasikova, Alla;Gaginskaya, Elena
利用鸡、日本鹌鹑和火鸡发育卵母细胞的巨型灯刷染色体(LBC)，精确分析了41-BP重复序列的染色体分布，即鸡基因组中的CNM和PO41重复序列，以及日本鹌鹑中的BglII重复序列。PO41重复序列在所有加利形目物种中都是保守的，而其他重复序列是物种特有的。在鸡和鹌鹑中，着丝粒和亚端粒区域共享同源的卫星序列。RNA聚合酶II转录着丝粒和亚端粒区域的41BP重复序列。在灯刷阶段注射到卵母细胞中的BrUTP掺入证明了这些重复序列的持续转录。与CNM和PO41重复序列两条链互补的RNA存在于鸡的LBC环中，而链特异的富含G的转录本是日本鹌鹑BglII重复序列的特征。来自41-bp重复序列的RNA不进行共转录U SnRNP依赖的剪接。同时，用hnRNP蛋白K富含CNM和PO41重复序列富含C-RNA的转录单位的核糖核蛋白基质，并对卫星转录的潜在启动子进行了讨论。
The chromosomal distribution of 41-bp repeats, known as CNM and PO41 repeats in the chicken genome and BglII repeats in the Japanese quail, was analyzed precisely using giant lampbrush chromosomes (LBC) from chicken, Japanese quail, and turkey growing oocytes. The PO41 repeat is conserved in all galliform species, whereas the other repeats are species specific. In chicken and quail, the centromere and subtelomere regions share homologous satellite sequences. RNA polymerase II transcribes the 41-bp repeats in both centromere and subtelomere regions. Ongoing transcription of these repeats was demonstrated by incorporation of BrUTP injected into oocytes at the lampbrush stage. RNA complementary to both strands of CNM and PO41 repeats is present on chicken LBC loops, whereas strand-specific G-rich transcripts are characteristic of BglII repeats in the Japanese quail. The RNA from 41-bp repeats does not undergo cotranscriptional U snRNP-dependent splicing. At the same time, the ribonucleoprotein matrix of transcription units with C-rich RNA of CNM and PO41 repeats was enriched with hnRNP protein K. Potential promoters for satellite transcription are discussed.