Transcriptome Analysis Of The Young Panicle In Stamen Formation Stage Of OsRhoGDI2 Overexpression Rice

Rice OsRhoGDI2 gene is a proteon-coding gene,isolated from the young panicle in stamen formation,and interacted with rice Rho protein OsRacD.Transgenic experiments in the laboratory found that over-expression of OsRhoGDI2 had a significant effect on the yield traits of panicle length,grains per spike and seed setting rate.The expression of OsRhoGDI2 gene suggests that the gene may be related to the development of young spikelets.On the basis of this study,over-expressing transgenic rice of OsRhoGDI2(OE-GDI2)screened and identified in T4 and T5 generations,The differential expression genes of young spikelets between wild-type(WT)and OE-GDI2 were compared by RNA-seq,and through follow-up bioinformatics analysis obtained phenotypic changes of OE-GDI2 in the molecular basis and related processes,established foundation to study the molecular mechanism of rice panicle length,grain number per spike,seed setting rate,and to elucidate the function of the gene in the development of rice panicle.The OE-GDI2 was screened and identified in T4 and T5 generations by PCR and qRT-PCR,and the statistical analysis was performed its yield-related traits.The results showed that OE-GDI2 in T4 and T5 generations were positive plants more than 96%,the expression level of OsRhoGDI2 gene was 2 to 5 times higher than that of control group in transgenic rice.The statistical analysis of OE-GDI2 agronomic characters in T4 generation showed that Spike length was shorter than WT average about 1cm,and the average number of grains per spike was more than 15 grains.Its was took young panicle in stamen formation,selected OE-GDI2 and WT in T4 generation each 3,and performed transcriptome analysis and comparison.The results showed that there were 584 differential expression genes in OE-GDI2 and WT rice young panicles,among 283 genes were up-regulated and 301 genes were down-regulated.;after the gene functional clustering analysis of KEGG,the differential expression genes were mainly related to the protein processing in endoplasmic reticulum,starch and sucrose metabolism and carbon metabolism.KEGG clustering analysis of up-regulated genes in transgenic rice showed that the differential expression genes were mainly related to ribosome,plant hormone signal transduction and carbon metabolism;suggested that the phenotypic changes in OE-GDI2 may be closely related.to protein synthesis,glucose metabolism and plant hormone signal transduction and other pathways.The differential expression genes in plant hormone signal transduction and carbon metabolism pathways screened by RNA-seq was validated by qRT-PCR;the results showed that RNA-seq results consistent with the gene were Up to 85.7%,indicating more reliable of RNA-seq results.The contents of four plant hormones,including IAA,ABA,CTK and JA,were determined in rice panicles,which identified OE-GDI2 rice young panicles of T5 generation.The results showed that the contents of IAA,ABA,ZR and MeJA in OE-GDI2 were significantly lower than those in WT,suggesting that changes in IAA,ABA,CTK and JA contents may be related to phenotypic changes in rice spike.In this study,the OE-GDI2 was screened and identified in T4 and T5 generations,and performed statistical analysis in the yield traits of transgenic rice.On this basis,the differential expression genes and the related metabolic pathways were analyzed in the young spikelets by RNA-seq,the contents of IAA,ABA,CTK and JA in transgenic rice were detected.and the relationship between the phenotypic changes of transgenic rice and the plant hormone signal transduction was analyzed from the perspective of hormone metabolism,Which laid the foundation for the molecular mechanism of OsRho GDI2 gene affecting rice yield traits.