摘要
FZP是水稻中控制小穗分化的一个关键基因 ,先前已将它定位在第 7染色体上。通过进一步对该基因进行精细定位和图位克隆 ,找到 2个SSR标记NRM6和NRM8,将该基因锁定在一个遗传距离为 1 2cM的范围内 (两标记与目标基因的遗传距离分别为 0 2cM和 1 0cM) ,相应的物理距离为 14 4kb。发现在预期的目标基因位置 ,存在一个具有类似AP2结构域的基因。已知AP2是一个控制植物花发育的重要基因。因此 ,这个基因应是FZP的一个候选基因。PCR扩增结果显示 ,突变体中该基因有一个大约 4kb的插入片段 ,与fzp共分离。由此可以初步认为 ,该基因就是FZP。
FZP is a key gene for spikelet differentiation in rice.Mutation of the gene blocks the differentiation of spikelets and makes rachis branches develop unlimitedly.A mutant of the gene named frizzle panicle (fzp) was previously found from the high generation progeny of a cross between two Oryza sativa ssp. indica rice varieties,V20B and Hua1B.With the mutant, FZP had been mapped to a chromosomal region of about 26 4 cM in width between two SSR (Simple Sequence Repeat) markers,RM172 and RM18,on chromosome 7.In this study,high resolution mapping of the gene was carried out for the positional cloning of the gene.Two flanking SSR markers,NRM6 and NRM8,were identified,which are 0 2 cM and 1 0 cM apart from the target gene,respectively,bracketing the target gene within an interval of 1 2 cM or 144 kb.An APETALA2 (AP2) domain like gene was found at the expected position of FZP .As AP2 is known to play an important role in the floral development,we took it as the most possible candidate of FZP .PCR analysis showed that the mutant allele of the AP2 domain like gene contains an insert of about 4 kb in length,suggesting that the gene is very likely FZP .
基金
国家 8 63计划 (编号 :2 0 0 1AA2 2 2 2 71)
国家 973规划~~
