Fu Y H, Marzluf G A
Department of Biochemistry, Ohio State University, Columbus 43210-1292.
Mol Cell Biol. 1990 Mar;10(3):1056-65. doi: 10.1128/mcb.10.3.1056-1065.1990.
The nitrogen regulatory circuit of Neurospora crassa consists of a set of unlinked structural genes which specify various nitrogen catabolic enzymes plus control genes and metabolic effectors which regulate their expression. The positive-acting nit-2 regulatory gene is required to turn on the expression of the nitrogen catabolic enzymes during conditions of nitrogen limitation. The complete nucleotide sequence of the nit-2 gene was determined. The nit-2 mRNA is 4.3 kilobases long and has a long nontranslated sequence at both its 5' and 3' ends. The nit-2 gene nucleotide sequence can be translated to yield a protein containing 1,036 amino acid residues with a molecular weight of approximately 110,000. Deletion analyses demonstrated that approximately 21% of the NIT2 protein at its carboxy terminus can be removed without loss of function. The nit-2 protein contains a single putative Cys2/Cys2 zinc finger domain which appears to function in DNA binding and which has striking homology to a mammalian trans-acting factor, GF-1.
粗糙脉孢菌的氮调节回路由一组不连锁的结构基因组成，这些结构基因指定了各种氮分解代谢酶，以及控制基因和调节它们表达的代谢效应物。在氮限制条件下，需要正向作用的nit-2调节基因来开启氮分解代谢酶的表达。测定了nit-2基因的完整核苷酸序列。nit-2 mRNA长4.3千碱基，在其5'和3'末端都有长的非翻译序列。nit-2基因核苷酸序列可被翻译产生一种含有1036个氨基酸残基、分子量约为110,000的蛋白质。缺失分析表明，在其羧基末端约21%的NIT2蛋白可以被去除而不丧失功能。nit-2蛋白包含一个单一的假定Cys2/Cys2锌指结构域，该结构域似乎在DNA结合中起作用，并且与哺乳动物反式作用因子GF-1具有显著的同源性。
