Arabidopsis STERILE APETALA, a multifunctional gene regulating inflorescence, flower, and ovule development
Arabidopsis STERILE APETALA, a multifunctional gene regulating inflorescence, flower, and ovule development
复制标题
DOI：
10.1101/gad.13.8.1002
复制
发表时间：
1999-04-15
影响因子：
10.5
通讯作者：
Angenent, GC
中科院分区：
文献类型：
--
作者：
Byzova, MV;Franken, J;Angenent, GC
拟南芥 STERILE APETALA (SAP) 的隐性突变会导致花序、花和胚珠发育严重异常。在汁液花中，萼片是心皮状的，花瓣短而窄或无，配子体形成，在第一次减数分裂期间或之后在汁液胚珠中停滞。在花同源异型基因 APETALA2 (AP2) 的汁液和突变等位基因之间的双突变体中观察到更严重的畸变，表明这两个基因都参与雌配子体发育的起始。 SAP 与器官特性基因 AGAMOUS (AG) 一起是维持花特性所必需的，其作用方式与 APETALA1 类似。与sap突变体花中的外部两个花器官相反，ag/sap双突变体中正常的萼片和花瓣发育，表明SAP负向调节花被轮中的AG表达。原位杂交实验显示 SAP 突变体中 AG 的异位表达，支持了 SAP 的这种假定的地籍功能。我们通过转座子标记克隆了 SAP 基因，并揭示了它编码一种具有序列基序的新型蛋白质，该蛋白质也存在于植物和动物转录调节因子中。与突变表型一致，SAP 在花序和花分生组织、花器官原基和胚珠中表达。综上所述，我们认为 SAP 属于一类新的转录调节因子，对于拟南芥花发育的许多过程至关重要。
A recessive mutation in the Arabidopsis STERILE APETALA (SAP) causes severe aberrations in inflorescence and flower and ovule development. In sap flowers, sepals are carpelloid, petals are short and narrow or absent, gametophyte formation, is arrested in sap ovules during or just after the first meiotic division. More severe aberrations were observed in double mutants between sap and mutant alleles of the floral homeotic gene APETALA2 (AP2) suggesting that both genes are involved in the initiation of female gametophyte development. Together with the organ identity gene AGAMOUS (AG) SAP is required for the maintenance of floral identity acting in a manner similar to APETALA1. In contrast to the outer two floral organs in sap mutant flowers, normal sepals and petals develop in ag/sap double mutants, indicating that SAP negatively regulates AG expression in the perianth whorls. This supposed cadastral function of SAP is supported by in situ hybridization experiments showing ectopic expression of AG in the sap mutant. We have cloned the SAP gene by transposon tagging and revealed that it encodes a novel protein with sequence motifs, that are also present in plant and animal transcription regulators. Consistent with the mutant phenotype, SAP is expressed in inflorescence and floral meristems, floral organ primordia, and ovules. Taken together, we propose that SAP belongs to a new class of transcription regulators essential for a number of processes in Arabidopsis flower development.