Abstract:

A full-length cDNA encoding fructose-6-phosphate, 2-kinase/fructose-2,6-bisphosphatase from maize (Zea mays L.) was cloned by the methods of reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE), and designated as mF2KP. The encoded protein is composed of two regions. Its COOH-terminal region is catalytic region and homologous to the enzymes from other eukaryotes; and its NH2-terminal region is common and special region only in plant. A truncated fragment of mF2KP covering integrated catalytic region was expressed in Escherichia coli. The fusion protein had the activities of fructose-6-phosphate, 2-kinase as well as fructose-2,6-bisphosphatase. Northern blot showed that the transcript level of mF2KP in seedlings initiated from strong-vigor seeds is lower than that from weak-vigor seeds. Key words: maize;fructose-2,6-bisphosphate;fructose-6-phosphate,2-kinase/fructose-2,6-bisphosphatase; seed vigor

玉米果糖-6-磷酸,2-激酶/果糖-2,6-二磷酸酶基因的结构与表达分析

王东 杜喜玲 张红生 钱晓茵  杨金水 翟虎渠

（1. 南京农业大学作物遗传与种质创新国家重点实验室，南京210095；
2.  复旦大学生命科学院遗传学研究所，上海200433）

摘要： 通过RT-PCR ,结合RACE技术 ,得到了玉米 (Zeamays L .)果糖-6-磷酸 ,2-激酶 /果糖-2 ,6-二磷酸酶的全长cDNA克隆 ,命名为mF2KP。氨基酸序列同源性比较发现 ,mF2KP蛋白可以分为两个部分 :C端包含高度保守的催化功能区 ,N端为植物中特有的多肽。将mF2KP基因中一段包含完整催化功能区的片段在大肠杆菌 (Escherichiacoli)中表达 ,融合蛋白具有果糖-6-磷酸 ,2-激酶 /果糖-2 ,6-二磷酸酶活性。Northern杂交证明在种子活力不同的幼苗中 ,mF2KP的转录水平存在明显差异。种子活力越高 ,幼苗中mF2KP的转录水平越低。
【关键词】：玉米；果糖-2，6-二磷酸；果糖-6-磷酸，2-激酶/果糖-2，6-二磷酸酶；种子活力

通讯作者。E-mail: hszhang@ njau.edu.cn。