Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114.
Proc Natl Acad Sci U S A. 1986 Sep;83(18):6825-8. doi: 10.1073/pnas.83.18.6825.
Nitrate is the major source of nitrogen taken from the soil by higher plants but requires reduction to ammonia prior to incorporation into amino acids. The first enzyme in the reducing pathway is a nitrate-inducible enzyme, nitrate reductase (EC 1.6.6.1). A specific polyclonal antiserum raised against purified barley nitrate reductase has been used to immunoprecipitate in vivo labeled protein and in vitro translation products, demonstrating that nitrate induction increases nitrate reductase protein and translatable mRNA. A partial cDNA clone for barley nitrate reductase has been isolated and identified by hybrid-selected translation. RNA blot-hybridization analysis shows that nitrate induction also causes a marked increase in the steady-state level of nitrate reductase mRNA.
硝酸盐是高等植物从土壤中吸收的主要氮源，但需要还原为氨，才能被整合到氨基酸中。还原途径中的第一个酶是硝酸盐诱导酶，即硝酸还原酶（EC 1.6.6.1）。一种针对纯化的大麦硝酸还原酶制备的特异性多克隆抗血清，已被用于免疫沉淀体内标记的蛋白质和体外翻译产物，证明硝酸盐诱导可增加硝酸还原酶蛋白和可翻译的 mRNA。已分离并通过杂交选择翻译鉴定出大麦硝酸还原酶的部分 cDNA 克隆。RNA 印迹杂交分析表明，硝酸盐诱导也会导致硝酸还原酶 mRNA 的稳态水平显著增加。
