致病疫霉组蛋白H2A变异体序列与表达

在真核生物中,DNA缠绕在组蛋白上形成核小体,一个组蛋白分子包括H2A、H2B、H3和H4各2个核心组蛋白亚基。在这4种核心组蛋白中,H2A富含多样化,且在细胞的生物途径中起重要作用的变异体,因此,H2A家族一直是研究热点。致病疫霉是重要的病原菌也是研究卵菌的模式物种之一,目前关于卵菌表观遗传的研究还未见报道。本研究针对致病疫霉组蛋白H2A变异体,利用基因组信息和基因芯片数据,通过序列比对、系统发育分析以及基因表达水平检测,发现在致病疫霉基因组中存在组蛋白H2A变异体H2A.X.1、H2A.X.2和H2A.Z,它们在不同生长发育阶段和侵染过程呈现特异的表达谱。研究结果为进一步研究致病疫霉表观遗传机制奠定了基础。

Sequence analysis and expression patterns of histone H2A variants in Phytophthora infestans

In eukaryotic cells, DNA is packaged inside the nucleus together with histones to form nucleosomes. Each histone molecule contains two of each core histone subunits H2A, H2B, H3 and H4. Among core histones, the H2A family is of great interest due to the high diversity of specialized variants. These variants have shown important role in critical cellular processes. Epigenetic mechanism in oomycetes is barely known. Phytophthora infestans is a severe pathogen and a model species in oomycetes. In this study, we studied the sequence and expression pattern of H2A variants of P. infestans through genome search, sequences alignment, phylogenetic analysis and realtime qPCR detection. P. infestans contains conserved genes encoding histone variants H2A.X.1, H2A.X.2 and H2A.Z, and these genes have specific expression patterns during development and infection stages. Our datasets provide useful inputs to help explore the epigenetic mechanisms of oomycetes.