The Expression Mode Of OsPIL15Gene And The Function In Rice Development

It had been reported that the phytochrome-interacting factors(PIFs)are very important in lightsignaling pathway in Arabidopsis thaliana. Sequence analysis showed that there are six potential PIFtranscription factors (OsPIL11-OsPIL16) in rice genome, but their expression and function are stillunknown.To access the biological functions of OsPIL15gene in rice growth, we analyzed theorgan-specificity of OsPIL15expression as well as effects of light and exogenous hormones on OsPIL15expression. The results show that the expression level of OsPIL15gene in leaves much higher than in otherorganizations, especially in the flag leaf is the highest, and the expression level in root and stem is higherthan the panicle, old spike and embryos. Which suggest that the expression of OsPIL15gene has obvioustissue specific, and controled by development, therefore, which imply that the OsPIL15gene have differentroles in different periods of the growth, and play an important role in feel the light signal. What more theexpression of the gene regulated by light cycle and biological clock.In order to further analysis the function of OsPIL15gene in photomorphosis of the plant, weconstruct the overexpression carrier of OsPIL15gene, and introduced into wild-type (WT), through thecomparision of transgenic and wild type rice plants phenotype, found that the overexpress lines didn'tgrown in the dark condition, but it grown normally in other light condition, which suggest light induced thegrowth of transgenic lines. In order to analyze the phenomenon of the dark condition, we tested theexogenous and endogenous ABA influence on the growth of transgenic lines. The results showed thatOsPIL15transgenic lines have very sensitive to exogenous ABA, and OsPIL15gene regulate theexpression of ABA synthesis related genes, but it not get the exact conclusion, so it is postulated that otherhormones also participate in this response process.Through analyze the phenotype of wild type and OsPIL15transgenic lines under white lightfound that up-ground height of the transgenic lines are significantly lower than wild type, and the angle ofthe second leaf and the second sheath are significantly larger than wild type, whatmore, transgenic lines areyellower than wild type, and it content low chlorophyll, therefore, OsPIL15gene negetive regulation the up ground length and chlorophyll synthetic, but positive regulation the sheath length,leaf length,leaf angleand stomata density. In addition, we analyze the flowering and sterility, the results showed that, comparedwith the wild type, the transgenic lines was delayed7-10days, so it suggest OsPIL15gene can delayflowering of plants, and it have significantly differences in effective tiller number,spike length,spike weigtand seed set percentage that OsPIL15gene regulate fertility of rice, so the next step we will analyzed therelationship of OsPIL15gene with the fertility.