| In flowering plants, tapetum plays an important role in pollen development. The rice (Oryza sativa) male sterile mutant, tapetum degeneration retardation (tdr), exhibit aborted degeneration of the tapetum and middle layer, as well as collapse of microspores. The TDR is preferentially expressed in the tapetum and encodes a putative basic/helix-loop-helix protein. We are selection,verification and function of TDR dowmstream-genes by ChIP and ChIP-sequence, The major research results presented in this study are briefly summarized as following:1 The DNA fragments of upstream promoter region of genes regulated by TDR have been isolated by using ChIP and ChIP-sequence. The 151 downstream genes are shown to be likely direct targets of TDR2 The ChIP technology could identify the TDR downstream-genes and primraryly proved the ChIP-sequence results by ChIP-PCR towards 20 possible TDR down-regulated genes3 Study on possible downstream-gene Os503 through Real-Time ChIP-PCR in vivo and EMSA in vitro. It proves that Os503 directly regulated by the TDR in specific binding E-box sites of Os503 upstream promoter region, as well as ChIP-sequence provide corroboration.4 The T-DNA insertion mutant of Os503 have been obtained, with identifying the mutant, its main phenotype is the appearance of sterile pollen at the stage of pollen maturation, which then leads to the decrease of the sterility degree.5 Analysis the special expression pattern of Os503 gene through RT-PCR and in situ showed that this gene is expressed largely form the vacuolated stage to the heading stage of the anther development, and it is mainly expressed in the tapetum and the microspore of the anther.What mentioned above indicate that Os503 is regulated by TDR, and it functions in the process of the tapetum and microspore of the anther in rice. |
