烟草NPR1基因家族鉴定及其在南方根结线虫胁迫下的表达分析OA北大核心CSTPCD

The research was aimed to mining the non-expressor of PR genes(NPR1)family members in-volved in tobacco resistance to the Meloidogyne incognita disease.Members of the tobacco NtNPR1 gene family were identified and analyzed using bioinformatics method based on the protein sequences of AtNPR1 family members in Arabidopsis.Relative expression level of key candidate resistance genes of NtNPR1 family in tobac-co resistant(NC95)and susceptible(Changbohuang,CBH)varieties infected by M.incognita were analyzed by qRT-PCR.The endogenous salicylic acid(SA)content in roots of the two tobacco varieties were measured by LC-MS/MS.The results showed that a total of 12 NtNPR1 genes were identified from the genome of com-mon tobacco,which were classified into three subgroups.Within each subgroup,the protein structure and con-served motif length and position of NtNPR1 family members were highly similar.The length of encoded amino acids ranged between 462 and 588 aa,and all of them were hydrophilic and localized in nucleus.After being infected with M.incognita,the SA content and expression level of NtNPR1 family members in roots increased in the resistant variety and decreased in the susceptible variety,among which,NtNPR6 changed the most ob-viously.In conclusion,the NPR1 gene is closely related to tobacco resistance to M.incognita,and the Nt-NPR6 gene could be used as a critical gene in response to M.incognita stress.