Isolation And Expression Analysis Of CsRDRs In Root-Knot Of Cucumis Sativus L.

RDRs (RNA-dependent RNA polymerase, RDRP) are widespread in eukaryotes, and plants have four kinds of RDRs, its members involved in plant growth, participate in multiple control function. In order to determine the type of RDR genes involving in the root-knot development of cucumber, five CsRDR genes were isolated from cucumber. And the CsRDR gene sequences and expressing characterics were analyzed). The main results are as follows:1. The research uses RT-PCR approaches to isolate genes related to root-knot formation based on genome sequence of Cucumis sativus L. inbred lines. Five CsRDR genes were isolated from Cucumis sativus L, including CsRDR1a, CsRDR1b, CsRDR1c, CsRDR2 and CsRDR6 (GenBank accession No. HQ738485-HQ738489). Localization of CsRDR on Cucumis sativus L. chromosomes showed CsRDR1a,CsRDR1b and CsRDR1c on chromosome 5 while chromosomes 1 and 2 had CsRDR2 and CsRDR6, respectively.2. The CsRDR protein sequences contained the characteristic gene sequence of eukaryotes DbDGD (b is F in RDR3, is L in RDR1, RDR2, RDR6). Phylogenetic analysis of RDRs from different plant.CsRDR1a,CsRDR1b and CsRDR1c belonging to the group I of RDR, CsRDR2 belonging to the group II and CsRDR6 belonging to the group IV.3. qPCR analysis showed that the expression of CsRDR1a, CsRDR1b, CsRDR2, CsRDR6 increased at different levels in different stages upon Meloidogyne incognita infection. CsRDR1a, CsRDR2 and CsRDR6 displayed a significant increase in expression at the early stage (6 hours after M. incognita infection), while the expression of CsRDR1b was enhanced at 36 hours after the inoculation. The results revealed that CsRDR genes were related to the root-knot development of Cucumis sativus, which laid a foundation for the prevention of root-knot nematode through molecular breeding technology.