中国梨S-RNase基因启动子的TAIL-PCR克隆及功能预测

Clone and functional prediction of S-RNase promoter regions in Chinese pear

利用TAIL-PCR技术从中国砂梨品种‘金花’、‘懋功’及白梨品种‘鸭梨’基因组DNA中分别扩增出长度为854、1448和1137bp的S13-、S12-、S21-RNase基因5′端上游序列,并提交GenBank,序列号为HM047239、HM047240、HM047241。经PLACE和PlantCARE软件顺式调控元件预测发现,这3个启动子均具有典型核心启动子TATA盒和CAAT盒,且在上游均存在光应答调控元件(box4,G-box)、脱落酸应答元件ABRE及水杨酸应答元件TCA-element等,由此可知其可能受光照、脱落酸、水杨酸等多种条件的共同调节。此外,与已知日本梨S2-、S3-、S4-、S5-RNase基因启动子序列比对发现,S-RNase启动子TATA盒上游存在一约200bp的同源区域。以MEG4.0构建系统发育树表明,梨属和苹果属S-RNase等位基因多态性可能在亚科的分化之前就已形成。

Using TAIL-PCR, 5′-flanking regions of the S_13-, S_12-, S_21-RNase genes with a length of 854 bp, 1 448 bp and 1 137 bp were successfully isolated from ‘Jinhua’and ‘Maogong’（Pyrus pyrifolia） and ‘Yali’（Pyrus bretschneideri） genomic DNA, the GenBank numbers are HM047239, HM047240 and HM047241. The core promoter regions and some upstream regulatory elements in the three fragments were analyzed using PLACE and PlantCARE software. It is found that all of these genes have the putative TATA box and CAAT box, and the promoters were affected by a variety of conditions as light, ABA, salicylic acid. Alignment analysis for promoter sequences of S_13-, S_12-, S_21-with 5′flanking sequences of S_2-, S_3-, S_4-, S_5-revealed a homologous region of about 200 bp in the upstream sequences of the TATA box in S-RNase promoters. Phylogenetic tree constructed by MEG 4.0 suggests that the divergence of S-RNase gene was formed before the differentiation of subfamilies.