拟南芥PPRs基因与莲座叶衰老之间的关系  

Relationship between pentatricopeptide repeat gene PPRs and rosette leaf senescence in Arabidopsis

作　　者：朱正火 任育军[1] 李燕云[1] 缪颖[1] 

机构地区：[1]福建农林大学生命科学学院分子细胞和系统生物学中心,福建福州350002

出　　处：《福建农林大学学报（自然科学版）》2016年第3期282-289,共8页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

基　　金：国家自然科学基金项目(31470383);国家自然科学基金青年项目(31400260);福建省"百人计划"基金

摘　　要：研究了拟南芥中一个PPR(称PPRs)基因与莲座叶片衰老之间的关系.实时定量PCR分析发现这个基因在生长7周的拟南芥各种组织中几乎都有表达,在莲座叶、花序和角果中的表达较高,在莲座叶中的表达随植株的生长和衰老进程呈不断下降的趋势.体外衰老相关因素处理试验结果显示,在4周的莲座叶中因进行离体处理,叶片衰老的程序提前启动,PPRs基因的表达降至6周时叶片中的水平,而茉莉酸,冷、热和干旱处理则延缓了PPRs表达水平的降低.通过鉴定获得PPRs的超表达和反义抑制转基因植株,并对植株的莲座叶衰老表型进行观察,发现超表达和反义抑制植株叶片的衰老进程与野生型相比并无太大差别,但在茉莉酸处理后PPRs超表达植株表现出延迟衰老的表型.在超表达植株中检测一些与叶片衰老相关基因的表达,发现与野生型相比有些基因的表达出现明显变化.以上结果表明这个PPRs基因在拟南芥中可能在某种程度上参与了一些外源因素诱导下加速生长期拟南芥莲座叶片衰老进程的负调节.Pentatricopeptide repeats （PPR） play important roles in plant growth, development and dealing with endogenous and ex-ogenous stresses. To elucidate the function of a PPR gene （PPRs） on the regulation of rosette leaf senescence in Arabidopsis, real-time qPCR analysis was applied to evaluate the relative transcription level of PPRs gene in different tissues and organs in 7-week-oldwild-type Arabidopsis. Meanwhile, the 4th week old plants were treated with phytohormones, including jasmonic acid （JA） , salicylicacid （SA）, abscisic acid （ABA）, auxin （IAA） and gibberellins （GA3）, and abiotic treatments （coldness, hotness, wounding,drought, darkness and H2O2 ） for 24 hours. Results showed that the relative expression of PPRs gene was higher in rosette leaves,flowers and siliques than in the other tissues of the wide-type plants, and the relative expression decreased significantly in rosetteleaves when their senescence initiated. After being treated with various stresses, the relative expression of PPRs gene in 4-week-oldplants dropped to that of 6-week-old plants compared with the control plants, though JA, coldness, hotness, and drought-treatedplants had significantly higher expression of PPRs gene than other treatments. Phenotypes of rosette leaf at senescence period werealmost the same among over-expressing （OE-PPRs）, antisense-PPRs （AN-PPRs）, and wild-type plants. Nevertheless, leaf senes-cence of JA-treated OE-PPRs plants was significantly retarded compared with the wild-type, and it was consistent with variations inthe expression of senescence-associated genes between OE-PPRs and wild-type plants. This study has provided insight into the nega-tive regulation of PPRs gene in rosette leaf senescence period.

关 键 词：PPR基因 叶片衰老 拟南芥 超表达转基因植株 

分 类 号：Q291[生物学—细胞生物学]