不同氮源对小麦幼苗谷氨酰胺合成酶的影响  

INFLUENCE OF NITROGEN SOURCES ON GLUTAMINE SYNTHETASE IN WHEAT SEEDLING

作　　者：黄勤妮[1] 印莉萍[1] 柴晓清[1] 刘祥林[1] 洪剑明[1] 赵微平[1] 

机构地区：[1]首都师范大学生物系,北京100037

出　　处：《Acta Botanica Sinica》1995年第11期856-862,共7页Acta Botanica Sinica（植物学报：英文版）

摘　　要：利用ＤＥＡＥ－纤维素柱层析、酶活性测定、Ｎｏｒｔｈｅｒｎ 分子杂交等技术，研究了小麦（Ｔｒｉｔｉｃｕｍ ａｅｓｔｉｖｕｍ Ｌ．）幼苗的根、叶和离体叶在不同氮源培养条件下谷氨酰胺合成酶（ＧＳ）活性和同工酶变化， 以及不同氮源对ＧＳ基因转录－ＧＳ－ｍ ＲＮＡ 的影响． 同时与硝酸还原酶（ＮＲ）活性进行比较， 结果表明∶当以ＮＨ＋４ 作唯一氮源时，小麦幼苗根谷氨酰胺合成酶（ＧＳｒ）和叶细胞质谷氨酰胺合成酶（ＧＳ１）活性要比以ＮＯ－３ 作唯一氮源的高．当以ＮＯ－３ 为唯一氮源时， ＮＯ－３ 则促进完整叶片和离体叶片叶绿体谷氨酰胺合成酶（ＧＳ２）活性． 从转录水平上看，ＮＨ＋４ 促进根ＧＳ－ｍ ＲＮＡ 的合成，而ＮＯ－３ 促进叶ＧＳ－ｍ ＲＮＡInfluence of nitrogen sources on the activity of glutamine synthetase(GS),GS isozymes and GS mRNA in wheat (Triticum aestivum L.) seedlings has been studied by DEAE cellulose column chromatography,enzyme activity assay and Northern blot technique,and activity of GS and nitrate reductase (NR) was compared.The results indicated that the activity of GS in roots (GSr) and cytoplasmic GS (GS1) in both intact and excised leaves was higher with NH + 4 N as the sole nitrogen source than with NO 3 - N. However, NO - 3 promated the activity of chloroplasmic GS (GS2) in leaves of wheat with NO - 3 N as the sole nitrogen surce. On the level of transcription, NH + 4 raised the level of GS mRNA in roots, but NO - 3 raised the level of GS mRNA in leaves of wheat seedling.

关 键 词：小麦 谷氨酰胺合成酶 氮源 

分 类 号：S512.101[农业科学—作物学]