盐胁迫下大麦幼苗多胺与脯氨酸合成竞争前体L-Arg  

The Biosyntheses of Polyamines and Proline Competed for Precursor L-Arginine in Barley Seedlings under Salt Stress

作　　者：赵福庚[1] 孙诚[1] 刘友良[1] 章文华[1] 

机构地区：[1]南京农业大学农业部作物生长调控重点实验室,江苏南京210095

出　　处：《作物学报》2001年第5期622-626,共5页Acta Agronomica Sinica

基　　金：国家自然科学基金资助项目 (批准号 :30 0 70 45 5)

摘　　要：20 0 mmol/L Na Cl处理结合 14 C- Arg叶面饲喂 6日龄大麦幼苗 ,以 L - Arg(精氨酸 )为前体合成的 Pro(脯氨酸 )和 PAs(多胺 )含量显著上升。处理同时在心叶中滴加 ADC(精氨酸脱羧酶 )抑制剂 D-Arg,游离 Pro放射性明显上升 ,滴加精氨酸酶和鸟氨酸氨基转移酶抑制剂 L - Lys,则游离 Put(腐胺 )和 PAs总放射性明显上升。在心叶中滴加 Put,游离 Pro放射性明显提高 ,而滴加 Pro则游离 Put和PAs总放射性不同程度上升。心叶滴加谷氨酰胺转移酶抑制剂邻菲咯啉 ,造成 PAs总放射性下降 ,但游离 Put放射性明显上升 ,从而促进了 Pro放射性的提高。上述结果表明大麦幼苗中 PAs和 Pro的合成竞争共同前体 L-Six day old barley seedlings were put under salt stress of NaCl 200 mmol/L and 14 C Arg was spreaded on leaves. The result showed that contents of proline(Pro) and polyamines (PAs) biosynthesized from Larginine(L Arg) increased remarkably. In addition, with arginine decarboxylase(ADC) inhibitor D Arg dropping into spindle leaves, the radioactivity of free Pro raised dramatically, but that of free Put and total PAs increased sharply when arginase and ornithine aminotranferase (OAT) inhibitor L Lys was dropped. Dropping putrescine(Put) into spindle leaves results in increment of free Pro obviously, while dropping Pro, the radioactivities of free Put and total PAs increased at various extent. When treated with transglutaminase (TGase) inhibitor O phenanthroline at the same way, it led a decrease in total PAs radioactivity and an increase in free Put radioactivity, and promoted the radioactivity of Pro. These suggested that the competition for the same precursor L Arg exsisted in the biosyntheses of Pro and PAs under salt stress.

关 键 词：盐胁迫 脯氨酸 多胺 大麦 幼苗 精氨酸 合成 前体 竞争作用 

分 类 号：Q945[生物学—植物学]