外源ABA对低温胁迫下小桐子幼苗脯氨酸积累及其代谢途径的影响  

Effect of Exogenous Abscisic Acid on Proline Accumulation and Metabolic Pathways in Jatropha curcas Seedlings under Cold Stress

作　　者：邓凤飞 杨双龙[1] 龚明[1] 

机构地区：[1]云南师范大学生命科学学院、生物能源持续开发利用教育部工程研究中心、云南省生物质能与环境生物技术重点实验室,昆明650500

出　　处：《植物生理学报》2015年第2期221-226,共6页Plant Physiology Journal

基　　金：国家自然科学基金(31260169),国家自然科学基金(31260064);云南师范大学研究生科研创新基金

摘　　要：本文以小桐子为材料,研究了外源脱落酸(ABA)对低温胁迫下小桐子幼苗脯氨酸积累的影响。结果表明,低温胁迫(5℃)可促进小桐子幼苗体内脯氨酸的积累,上调脯氨酸合成关键酶Δ~1-吡咯琳-5-羧酸合成酶(P5CS)和鸟氨酸转氨酶(OAT)的活性,上调P5CS基因(JcP5CS)的表达,及抑制脯氨酸降解酶脯氨酸脱氢酶(Pro DH)的活性。用外源ABA处理低温胁迫下的小桐子幼苗,发现150μmol·L^(-1)的ABA可显著提高其低温胁迫下的脯氨酸含量,上调P5CS的活性和JcP5CS的表达水平,及抑制ProDH的活性。表明外源ABA可通过活化脯氨酸合成的谷氨酸途径和抑制脯氨酸的降解途径来促进低温胁迫下小桐子幼苗脯氨酸的积累。Jatropha curcas seedlings were used as materials to study the effect of exogenous abscisic acid （ABA） on proline accumulation under cold stress. The results showed that cold stress （5 ~C） led to a significant accumulation of proline in J. curcas seedlings. It also induced a rapid increase of activities of the key enzymes Al-pyrroline-5-carboxylate synthetase （P5CS） and ornithine aminotransferase （OAT） of proline biosynthesis, and an up-regulation ofP5CS gene （JcPSCS） expression, and a decrease of the activity of the key enzyme pro- line dehydrogenase （ProDH） of proline degradation. Treatment with 150 μmol·L-1 abscisic acid （ABA） could enhance the accumulation of proline in J. curcas seedlings under cold stress. ABA also increased the activity of P5CS, and improved the expression level of Jcp5cs. Furthermore, the ABA treatment decreased the activity of ProDH in Jr. curcas seedlings under cold stress. These results showed that the ABA-induced proline accumula- tion in the J. curcas seedlings under cold stress might be a combined result of the activation of glutamate path- ways of proline biosynthesis and inhibition of proline degradation pathway.

关 键 词：小桐子 低温胁迫 脱落酸 脯氨酸 代谢途径 

分 类 号：Q945.78[生物学—植物学]