摘要： 以苹果幼叶为试验材料,通过同源克隆和T-PC方法分离出B_LECTIN基因家族中的一个基因,命名为MdMBL。分析结果表明,克隆得到的MdMBL长度为1 181 bp,包括20 bp的5'非编码区、81 bp的3'非编码区和一个长度为1 080 bp编码359个氨基酸的开放阅读框,推测该蛋白质分子量为39.76 kDa,其等电点为8.72。在构建的MBL系统进化树中,MdMBL与葡萄的MBL的关系最近,其次为橹豆的MBL,与苹果的MBL2同源基因进化关系最远。相对荧光定量T-PC分析表明,MdMBL具有组织特异性,在茎中表达量最高,在花中表达量最低;低温胁迫促使MdMBL表达量升高,MdMBL在机械损伤处理下表达量先升高后降低;外源SA能够诱导MdMBL表达上调。

关键词: 苹果, 甘露糖结合凝集素, 基因克隆, 表达分析

Abstract: Mannose-binding Lectin(MBL),which belongs to B_LECTIN gene families,was isolated fom the young leaf of apple ( Malus domestica) by homologous cloning technology, named as MdMBL.The cDNA was 1 181 bp in length with an 5'non-coding egion of 20 bp,an 3'non-coding egion of 81 bp and an open eading fame ( OF) of 1 080 bp encoding a potein of 359 amino acids, and the estimated molecula weight and isoelectic point (pI)of the putative potein wee 39.76 kDa and 8.72,espectively.The phylogenetic tee of MBL showed that Md-MBL was closest with gapes MBL, followed by glycine max, and the evolutionay elationships of homologous genes in apple MdMBL2 was fathest.Quantitative eal-time PC analysis shows that the gene is tissue-specific and ex-pessed highest in stems, the lowest in flowes;The expession of MdMBL was pomoted inceased with the cold stess and the mechanical damage stess;Exogenous SA could induce up-egulation of MdMBL expession.

Key words: Malus domestica, Mannose-binding lectin( MBL), Gene cloning, Gene expession

中图分类号: 

• S661.1

• Q943