单 位：
中南林业科技大学经济林育种与栽培国家林业局重点实验室
关键词：
配子体自交不亲和;雪花梨;快速扩增cDNA末端;S16-RNase基因
摘 要：
通过逆转录PCR(RT-PCR)及快速扩增cDNA末端(RACE)技术从中国白梨品种雪花梨中克隆到S16-RNase基因的全长cDNA序列(GenBank接受号为DQ991388).该cDNA克隆总长1101bp,包含1个完整的开放阅读框,编码228个氨基酸.S16-RNase表现出梨S-RNase基因的基本结构特征,即其具有5个保守区(C1,C2,C3,RC4及C5)和1个高变区.在推导氨基酸水平上,S16-RNase与梨其他S-RNase基因的相似性为63%至74%,但与苹果S9-RNase的相似性高达95%.通过多序列比对构建进化树,分析梨S16-RNase与蔷薇科植物其他S-RNase基因的遗传进化关系.结果表明,S16-RNase与苹果亚科S-RNase基因形成一个亚科特异而非种特异的S-RNase基因类群;且不同S-RNase基因间存在属内种间遗传距离远于属间种间遗传距离现象.
译 名：
Cloning and sequence analysis of full length cDNA encoding S_(16)-RNase from 'Xuehua' pear(Pyrus bretschneideri Rehd.)
作 者：
TAN Xiao-feng, ZHANG Lin, YUAN De-yi, ZENG Yan-ling, JIANG Ao-fang (Key Lab of Non-wood Forest Product of Forestry Ministry, Central South University of Forestry and Technology, Changsha 410004, China)
关键词：
gametophytic self-incompatibility (GSI); 'Xuehua' pear; rapid amplification of cDNA ends; S16-RNase gene
摘 要：
The full length cDNA encoding S16-RNase (GenBank accession no. DQ991388) was cloned from styles of Chinese white pear (Pyrus bretschneideri Rehd.) cultivar 'Xuehua' by reverse transcription-PCR (RT-PCR) and rapid amplification of cDNA ends (RACE) technology. The S16-RNase cDNA contained 1101 nucleotides including a complete open reading frame (ORF) predicted to encode a protein of 228 amino acids. The S16-RNase displayed the basic structural features of pear S-RNases, i.e. five conserved regions (C1, C2, C3, RC4 and C5) and a hypervariable (HV) region. At the deduced amino acid level, S16-RNase showed 63% to 74% similarity with other pear S-RNases, whereas it showed an extremely high similarity (95%) with apple (Malus domestica Borkh.) S9-RNase. Based on multiple amino acid sequences alignment and phylogenetic tree construction, the evolutionary relationship between S16-RNase and other S-RNases of Rosaceae plants was investigated. Results show that S16-RNase clustered with maloideous S-RNases, forming a subfamily-specific S-RNase group but not a species-specific group. In addition, the genetic distance of S-RNases was greater among some intragenus species than that of among intergenus species.
