To elucidate the effects of nitrogen starvation on the expression of nitrogen assimilation related genes, ten ESTs were isolated in Micractinium pus ilium by using Suppression Subtraction Hybridization (SSH) , which showed high similarity to those genes involved in nitrogen assimilation. Real -time PCR confirmed that the transcript levels of seven genes were significantly increased after nitrogen starvation, including genes encoding nitrate reductase, NMT1/HI5 like domain protein, strombine dehydrogenase, oxidoreductase FAD/NAD(P)-binding, ribosomal proein L36a, cytochrome cdl-nitrite reductase-like and NADH:cytochrome b5 reductase. On the other hand, genes encoding aspartate aminotransferase, stomatin and gamma-glutamyl phosphate reductase were down-regualted by nitrogen starvation in Micractinium pusillum.%以微茫藻为材料,利用抑制差减杂交技术,分离鉴定了10种与已知功能基因具有较高同源性的基因片段,这些片段的同源基因均与氮源的吸收利用相关.实时荧光定量PCR验证了7种基因在氮缺乏条件下转录水平明显上调,包括:硝酸还原酶基因、NMT1/rHI5家族蛋白基因、N-羟甲基-L-丙氨酸脱氢酶基因、核糖体蛋白L36a基因、FAD/NAD (P)结合的氧化还原酶基因、NADH:细胞色素b5还原酶基因和细胞色素cd1-亚硝酸还原酶类似基因.而天冬氨酸转氨酶、红细胞膜蛋白7.2b和γ-谷氨酰磷酸还原酶这3种基因在氮缺乏时下调表达.
展开▼
