PDF(Pubmed)
Abstract：
BACKGROUND: The piRNA pathway in animal gonads functions as an \'RNA-based immune system\', serving to silence transposable elements and prevent inheritance of novel invaders. In Drosophila, this pathway relies on three gonad-specific Argonaute proteins (Argonaute-3, Aubergine and Piwi) that associate with 23-28 nucleotide piRNAs, directing the silencing of transposon-derived transcripts. Transposons constitute a primary driver of genome evolution, yet the evolution of piRNA pathway factors has not received in-depth exploration. Specifically, channel nuclear pore proteins, which impact piRNA processing, exhibit regions of rapid evolution in their promoters. Consequently, the question arises whether such a mode of evolution is a general feature of transposon silencing pathways.
RESULTS: By employing genomic analysis of coding and promoter regions within genes that function in transposon silencing in Drosophila, we demonstrate that the promoters of germ cell-specific piRNA factors are undergoing rapid evolution. Our findings indicate that rapid promoter evolution is a common trait among piRNA factors engaged in germline silencing across insect species, potentially contributing to gene expression divergence in closely related taxa. Furthermore, we observe that the promoters of genes exclusively expressed in germ cells generally exhibit rapid evolution, with some divergence in gene expression.
CONCLUSIONS: Our results suggest that increased germline promoter evolution, in partnership with other factors, could contribute to transposon silencing and evolution of species through differential expression of genes driven by invading transposons.
RESULTS: By employing genomic analysis of coding and promoter regions within genes that function in transposon silencing in Drosophila, we demonstrate that the promoters of germ cell-specific piRNA factors are undergoing rapid evolution. Our findings indicate that rapid promoter evolution is a common trait among piRNA factors engaged in germline silencing across insect species, potentially contributing to gene expression divergence in closely related taxa. Furthermore, we observe that the promoters of genes exclusively expressed in germ cells generally exhibit rapid evolution, with some divergence in gene expression.
CONCLUSIONS: Our results suggest that increased germline promoter evolution, in partnership with other factors, could contribute to transposon silencing and evolution of species through differential expression of genes driven by invading transposons.
摘要：
背景：动物性腺中的piRNA途径充当“基于RNA的免疫系统”，用于沉默可转座元素，防止小说入侵者的继承。在果蝇中,该途径依赖于三种与23-28个核苷酸的piRNAs相关的性腺特异性Argonaute蛋白（Argonaute-3，Aubergine和Piwi），指导转座子衍生的转录物的沉默。转座子构成了基因组进化的主要驱动力，然而，piRNA通路因子的进化尚未得到深入的探索。具体来说,通道核孔蛋白，影响piRNA加工，在它们的启动子中表现出快速进化的区域。因此,问题是，这种进化模式是否是转座子沉默途径的一般特征。
结果：通过对果蝇在转座子沉默中起作用的基因中的编码和启动子区域进行基因组分析，我们证明生殖细胞特异性piRNA因子的启动子正在经历快速进化。我们的发现表明，快速启动子进化是参与跨昆虫物种种系沉默的piRNA因子的共同特征。可能导致密切相关的分类群的基因表达差异。此外，我们观察到只在生殖细胞中表达的基因的启动子通常表现出快速进化，基因表达有一定差异。
结论：我们的结果表明，种系启动子进化增加，与其他因素合作，可以通过入侵转座子驱动的基因差异表达来促进转座子沉默和物种进化。
结果：通过对果蝇在转座子沉默中起作用的基因中的编码和启动子区域进行基因组分析，我们证明生殖细胞特异性piRNA因子的启动子正在经历快速进化。我们的发现表明，快速启动子进化是参与跨昆虫物种种系沉默的piRNA因子的共同特征。可能导致密切相关的分类群的基因表达差异。此外，我们观察到只在生殖细胞中表达的基因的启动子通常表现出快速进化，基因表达有一定差异。
结论：我们的结果表明，种系启动子进化增加，与其他因素合作，可以通过入侵转座子驱动的基因差异表达来促进转座子沉默和物种进化。
