摘要
以砂梨黑皮病易感品种‘翠冠’果实为材料,克隆获得了调控α-法尼烯合成的关键限速酶3-羟基-3-甲基戊二酸单酰辅酶A还原酶(HMGR)基因家族中的两个成员Pphmgr1和Pphmgr2。Pphmgr1开放阅读框为1827bp,编码由609个氨基酸残基组成的蛋白;Pphmgr2开放阅读框为1707bp,编码由569个氨基酸残基组成的蛋白。序列比对结果显示:‘翠冠’PpHMGR1和PpHMGR2与苹果果实的MdHMGR1和MdHMGR2蛋白的同源性分别达到了90%和98%。在采后货架期28～32℃条件下,乙烯受体抑制剂1-MCP可明显抑制果实呼吸速率,减缓乙烯释放,显著降低果皮中α-法尼烯及其氧化产物共轭三烯的含量,减少黑皮病发病率并减轻发病程度。半定量RT-PCR结果显示1-MCP处理后果皮中Pphmgr2的表达受到显著抑制,但是Pphmgr1的表达几乎不受影响。
In this study, Pphmgrl and Pphmgr2, two members of hmgr gene family which encodes α-farnesene metabolism rate-limiting enzyme HMGR were cloned from scald-susceptible sandy pear variety ‘Cuiguan’ peel, respectively. Pphmgrl cDNA has an open reading frame of 1 827 bp nucleotides and encodes a polypeptide including 609 residues which relative molecular mass was 64. 80 kD; While Pphmgr2 cDNA has an opening reading frame of 1 707 bp nucleotides and encodes a polypeptide including 569 residues which relative molecular mass was 60.21 kD. The deduced amino acid sequences were from PPHMGR1 and PPHMGR2 showed 90% and 98% homology with apple MdHMGR1 and MdHMGR2, respectively. Under high temperature shelf life condition （28 - 32℃） , ethylene receptor inhibitor 1-MCP significantly decreased respiration rate and alleviated ethylene production rate. At the same time, ct-farnesene and conjugated trienols contents were significantly decreased and occurring times of their peak values were postponed together. The semiquantitative RT-PCR results showed that Pphmgrl was constitutively expression, while expression of Pphmgr2 was inhibited by 1-MCP.
出处
《园艺学报》
CAS
CSCD
北大核心
2009年第7期959-966,共8页
Acta Horticulturae Sinica
基金
江苏省博士后基金项目(070213C)
江苏省农业科学院博士后基金项目(6510613)
江苏省农业科技自主创新项目(CX1071106)
