沙田柚S-RNase基因的克隆及序列分析

Cloning and Sequence Analysis of S-RNase Gene from Citrus grandis var.Shatinyu Hort

利用高通量测序技术对沙田柚自交和异交花柱进行转录组测序。通过差异分析得到沙田柚S-RNase基因序列。该基因全长为1 238bp(GenBank登录号为KP172529),开放阅读框(ORF)全长为834bp,共编码278个氨基酸,编码的蛋白质的相对分子质量为31.402kDa,理论等电点为5.30。S-RNase蛋白为亲水性蛋白,共有17个可能的磷酸化位点。氨基酸序列分析表明,其编码的氨基酸与柚Citrus maxima、沙糖桔Citrus reticulata和甜橙Citrus sinensis的同源性分别为99%、98%和96%。系统进化树显示沙田柚S-RNase基因与柚、沙糖桔和甜橙亲缘关系很近,属于同一进化分支。

In this paper, the transcriptome of the self-pollinated style and cross-pollinated style of Citrus grandis var. Shatinyu Hort were sequenced by high-throughput sequencing technology. S-RNase gene sequences of Citrus grandis var. Shatinyu Hort was obtained through different analytical method. It is 1 238 bp （GenBank accession number：KP172529） in length with an open reading frame（ORF）of 834 bp, encoding 278 amino acids with deduced molecular weight of 31.402 kDa, and theoretical pI value of 5.30. Bioinformatics analysis showed that S-RNase is a hydrophilic protein, and there are 17 phosphorylation sites within the polypeptide chain. The homology analysis of amino acid sequence indicated that the S- RNase protein shared high homology with that of Citrus maxima （99%）, Citrus reticulate （98%） and Citrus sinensis （96%）. Phylogenetic analysis revealed that S-RNase gene showed closer kinship with that of Citrus maxima, Citrus reticulate and Citrus sinensis, indicating that they belong to the same evolutionary branch.