由中國(guó)科學(xué)院昆明動(dòng)物研究所,、深圳華大基因研究院,、西南大學(xué),、上海腫瘤所等合作的研究成果“家蠶基因組甲基化譜”,，5月2日在國(guó)際著名學(xué)術(shù)雜志《自然—生物技術(shù)》（Nature Biotechnology）上發(fā)表,，這是中國(guó)科學(xué)家在家蠶基因組研究領(lǐng)域取得的又一項(xiàng)重要成果,。
作為表觀遺傳學(xué)的一種重要標(biāo)記，DNA甲基化在基因組防御,、基因調(diào)控等方面都發(fā)揮著重要作用,。相對(duì)于動(dòng)植物，昆蟲(chóng)甲基化水平很低,，其功能也一直存在爭(zhēng)議,。近年來(lái),，隨著越來(lái)越多昆蟲(chóng)甲基化基因和甲基化酶的報(bào)道，昆蟲(chóng)甲基化的功能和生物學(xué)意義引起了廣泛的興趣,。
最近,，中國(guó)科學(xué)院昆明動(dòng)物研究所王文研究員領(lǐng)導(dǎo)的馬普小組的相輝博士等，與深圳華大基因研究院,、西南大學(xué)蠶桑學(xué)重點(diǎn)實(shí)驗(yàn)室以及上海腫瘤所的朱景德研究員小組共同合作,，利用新一代測(cè)序技術(shù)構(gòu)建了第一張單堿基分辨率的昆蟲(chóng)甲基化譜——家蠶絲腺甲基化譜。
研究發(fā)現(xiàn)大約0.11%的基因組胞嘧啶被甲基化修飾,，比哺乳動(dòng)物和植物低至少50倍,。甲基化區(qū)域主要富集在基因區(qū)，并且與基因表達(dá)水平成正相關(guān),。動(dòng)植物中被報(bào)道發(fā)揮重要作用的啟動(dòng)子區(qū),、核糖體rDNA區(qū)甲基化調(diào)控，以及轉(zhuǎn)座子區(qū)的甲基化抑制,，在昆蟲(chóng)中似乎還不具備,。
家蠶甲基化譜的完成不但對(duì)理解昆蟲(chóng)表觀遺傳學(xué)調(diào)控的提供了重要的參考資料，也為進(jìn)一步發(fā)掘家蠶人工馴化過(guò)程中潛在的表觀遺傳學(xué)貢獻(xiàn)奠定了研究基礎(chǔ),。
（生物谷Bioon.com）
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Science：家蠶基因組測(cè)序成功
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生物谷推薦原文出處：
Nature Biotechnology DOI:10.1038/nbt.1626
Single base–resolution methylome of the silkworm reveals a sparse epigenomic map
Hui Xiang,Jingde Zhu,Quan Chen,Fangyin Dai,Xin Li,Muwang Li,Hongyu Zhang,Guojie Zhang,Dong Li,Yang Dong,Li Zhao,Ying Lin,Daojun Cheng,Jian Yu,Jinfeng Sun,Xiaoyu Zhou,Kelong Ma,Yinghua He,Yangxing Zhao,Shicheng Guo,Mingzhi Ye,Guangwu Guo,Yingrui Li,Ruiqiang Li,Xiuqing Zhang,Lijia Ma,Karsten Kristiansen,Qiuhong Guo,
Jianhao Jiang,Stephan Beck,Qingyou Xia,Wen Wang& Jun Wang et al.
Epigenetic regulation in insects may have effects on diverse biological processes. Here we survey the methylome of a model insect, the silkworm Bombyx mori, at single-base resolution using Illumina high-throughput bisulfite sequencing (MethylC-Seq). We conservatively estimate that 0.11% of genomic cytosines are methylcytosines, all of which probably occur in CG dinucleotides. CG methylation is substantially enriched in gene bodies and is positively correlated with gene expression levels, suggesting it has a positive role in gene transcription. We find that transposable elements, promoters and ribosomal DNAs are hypomethylated, but in contrast, genomic loci matching small RNAs in gene bodies are densely methylated. This work contributes to our understanding of epigenetics in insects, and in contrast to previous studies of the highly methylated genomes of Arabidopsis1 and human2, demonstrates a strategy for sequencing the epigenomes of organisms such as insects that have low levels of methylation.
