Study Of Genes Expression In Response To Chinese Cabbage (Brassica Campestris L.ssp.pekinensis) Root Infected By Plasmodiophora Brassicae Woron

Clubroot in Chinese cabbage caused by Plasmodiophora brassicae Woron is a soil-born disease worldwide that hazards cruciferous crops seriously. In this study, transcriptome sequencing technology(RNA-seq) was used to transcriptome sequencing of the root infected by Plasmodiophora brassicae Woron after inoculation. Mapped to different genomic databases, sequencing results were applied to functional annotation. Combinded with bio-technology platform, the differentially expressed genes was sclected in root tissue infected by Plasmodiophora brassicae Woron. The molecular mechanism in response to Chinese cabbage root infected by Plasmodiophora brassicae Woron was preliminary discussion from two aspects, namely, cell cycle and callose accumulation. The main research results were as follows:1. RNA-seq was applied in building the root transcriptome of Chinese cabbage, which obtained20.8Gb data totally. It assembled65128unigenes by Denovo. There were53045unigenes mapped to NT, NR, SwissProt, TrEMBL, KEGG, COG and GO database. There were4986genes which were found differentially expression after the root tissue was infected by Plasmodiophora brassicae Woron. Among them,3394genes expressed down-regulatedly and1592genes expressed up-regulatedly. There were111metabolic pathways including1672differential genes which were found by KEGG.2. Real-time quantitative PCR was applied to checking the relative expression of differential genes related to cell cycle if their|LOG2(TR/CK)|≥2. Multiple genes were expressed differentially in the root infected by Plasmodiophora brassicae Woron. The results of transcriptome sequencing were consistent with the expression analysis results of real-time quantitative PCR. Promoting genes such as CDKA;1, DOF1.7and CDKB1were up-regulated expression, while repressing gene such as DELLA-RGA1were down-regulated expression. Thus cell cycle was accelerating starting, which regulated cell proliferation.3. Real time quantitative PCR was employed in checking the the relative expression of differential genes related to callose deposition if their|LOG2(TR/CK)|≥2.Multiple genes were found differential expression in the root infected by Plasmodiophora brassicae Woron. The results of transcriptome sequencing were consistent with the expression analysis results of real-time quantitative PCR. Callose synthases, GSL3, GSL4and GSL6were down-regulated expression. While callase(β-1.3-glucanase), BG13, BG14were up-regulated expression. Thereby callose accumulation was inhibited, which caused that the defense function of cell wall declined.