水稻花药绒毡层特异表达基因RA39的克隆与表达特性分析

利用cDNA减法杂交，差异杂交筛选和RACE等技术。从水稻（Orza sativaL.ssp.japonica)中克隆了一个新的绒毡层特异性cDNA，其编码基因被命名为RA39。该cDNA长1013bp。编码由298个氨基酸残基组成的多肽RA39是一个单拷贝基因。在绒毡层细胞中特异性表达。在小孢子母细胞减数分裂期的绒毡层细胞中有较高的表达活性。用PSORT和PPSEARCH软件进行的结构分析揭示出RA39蛋白的N端是一个由17个氨基酸残基组成的信号肽，该蛋白包含一个跨膜区和一个胞质尾区两个主要结构域以及多个蛋白激酶的磷酸化位点。

Molecular Cloning and Characterization of the Tapetum- specific Gene RA39 from Rice

A novel tapetum_specific cDNA clone of rice, its corresponding gene designed as RA39, is isolated by RNA subtractive hybridization, differential screening and rapid amplification of cDNA ends. The RA39 cDNA is 1 013 bp in length with an open reading frame encoding 298 amino acid residues. mRNA in situ hybridization reveals that RA39 is a tapetum_specific gene, and highly expressed at the meiosis stage of pollen mother cells. The deduced protein contains a signal peptide, a transmembrane region and a cytoplasmic tail, and is predicted to localize in endoplasmic reticulum by PSORT program. This cDNA sequence did not show significant homology to any known sequences in Genbank database. RA39 is the first gene identified to be expressed specifically in tapetal cells at the meiosis stage of pollen mother cells from cereals.