红麻线粒体基因NAD3和COB的RNA编辑与表达分析

RNA editing and expression analysis of NAD3 and COBin mitochondria of kenaf

以红麻细胞质线粒体近等基因系UG93A(不育系)、UG93B(保持系)及UG93A×福红992(恢复系)的F1代为材料,研究花药线粒体基因NAD3和COB的转录与表达。结果发现,在3种供试材料中,基因NAD3的CDS区在DNA水平和RNA编辑水平上均无差异;不育系与保持系的COB基因DNA编码序列无差异,但在RNA水平上发生了编辑,8个位点的编辑均发生于密码子的第一或第二位碱基,且导致氨基酸种类变化,主要为亲水性氨基酸转变为疏水性氨基酸;COB基因在UG93A中的RNA编辑频率低于UG93B;NAD3和COB基因在3种材料中的转录本大小基本相同,但在表达水平上表现为不育系显著低于保持系和F1代。由此推测NAD3和COB基因在红麻花药发育过程中有着重要的作用。

Transcription and expression of NAD3 and COB were analyzed using F1 plant of three near isogenic mitochondria lines including UG93A（male sterile line）,UG93B（maintainer line）and UG93A×FuHong992（restorer line）kenaf as study materials.The results showed that：The coding sequence and RNA editing of NAD3 displayed no differences among these three lines;The coding sequence of COBis completely consistent,and there were 8editing sites of RNA editing,which occurred at the first or the second position of codons with alteration of amino acid type and was mostly converting hydrophilic amino acid into hydrophobic amino acid;The editing frequencies of COB were lower in sterile cytoplasm than in fertile cytoplasm;There was no size difference of NAD3 and COB mRNA in the three lines,but the expression level of NAD3 and COB was reduced significantly in UG93 Acompared to UG93 Band F1,indicating that NAD3 and COB might play an important role during the anther development of kenaf.