AMMECR1基因是引起邻近基因缺失综合症AMME疾病的可能候选基因之一。AMME疾病患者一般患有遗传性肾炎，同时部分患者还会出现智力迟钝、面部发育不全、红细胞性贫血等症状。AMMECR1基因广泛存在于各种生物类群中，在进化中高度保守。在结构上，AMMECR1蛋白含有两个RAGNYA折叠，有人推测它可能是一种与RNA加工或转运相关的酶，但其确切功能仍未见报道。 本论文初步研究了非洲爪蛙AMMECR1基因在胚胎发育中的功能与作用机制。非洲爪蛙具有两个AMMECR1相关基因，AMMECR1和AMMECR1L（AMMECR1-like）。在爪蛙胚胎发育过程中，AMMECR1和AMMECR1L基因都是母源性表达的，并且在胚胎中枢神经系统高表达。通过显微注射特异性反义Morpholino抑制AMMECR1和AMMECR1L的表达，胚胎发育出现严重畸形，并伴随有神经嵴发育缺陷。原位杂交结果显示，神经嵴和中枢神经系统的标记基因如FoxD3、Sox2等的表达显著降低，信号分子shh的表达也受到抑制。在培养细胞中，AMMECR1L蛋白在细胞核中呈不连续的点状分布，通过与核斑的标记蛋白SC-35共染色表明，该结构并不是核斑。通过酵母双杂交筛选，我们发现了两个可能的AMMECR1相互作用蛋白，核糖核蛋白hnRNP U和组蛋白甲基转移酶DOT1L。结合对公共蛋白相互作用数据库的分析，我们还验证了AMMECR1可能与tRNA代谢相关的CLP1蛋白相互作用。以上研究结果初步揭示了AMMECR1基因在胚胎发育中的功能，为进一步研究其作用机制提供了线索。; AMMECR1 (Alport syndrome, Mental retardation, Midface hypoplasia, and Elliptocytosis Chromosomal Region gene 1) gene is one of the candidate genes that cause AMME disease (a kind of contiguous gene deletion syndrome). AMME disease patients ordinarily suffer from Alport syndrome, some of them accompany with additional features including mental retardation, midface hypoplasia, and elliptocytosis. AMMECR1 gene exists in various organisms, The protein sequence encoded by this gene was very conserved during evolution. Structurally, AMMECR1 protein have two RAGNYA folds. It is speculated that AMMECR1 protein may be an enzyme related to RNA processing and transport. So far, there are no reports about the exact functions of this gene. In our study, we explored the functions and molecular mechanisms of AMMECR1 gene during embryonic development. X.laevis have two homologous genes, AMMECR1 and AMMECR1L（AMMECR1-Like）. AMMECR1 and AMMECR1L genes are maternal expressed in X.laevis embryos, and strongly expressed in central nervous system. After knock down these genes by specific antisense morpholino, X. laevis embryos emerged severely malformations at tailbud stage, accompanied defects in neural crest development. Also the expression of neural crest and central nervous system marker genes FoxD3 and Sox2 have been affected, shh was downregulated too. In cultured cells, AMMECR1L-EGFP fusion protein distributed discreted points in nucleus.But these speckles can not be co-localization with SC35, a maker protein of nucleus speckles, so we rule out the possibility that these points are nucleus speckles. Through yeast two-hybrid screen, we find some proteins including hnRNP U and DOT1L may interact with AMMECR1. After analysis of the public protein interaction database, we explored the potential interactions between AMMECR1 and CLP1(tRNA metabolism related protein). Our data above preliminary revealed the functions of AMMECR1 gene during embryonic development, provide clues for further study of its mechanism.
修改评论