Identification Of Brassica Napus Anthocyanin-susceptible Mutant As And Its Response To Adverse Stress

Anthocyanins,as one of the most important natural pigments in plants,are not only beneficial to plant pollination and seed propagation and to human health as well.Besides,they also play an influential role in adverse stress conditions.The Brassica napus anthocyanin-susceptible mutant as(anthocyanin-susceptible)obtained previously was used as the research object in the present study.The mutation traits investigation and proteomics research methods were used to study the molecular mechanisms and physiological changes of mutations of the anthocyanin-susceptible mutant as.The anthocyanin-susceptible mutant as was a natural mutant of Brassica napus from cv Zhongshuang 11.The mutant was prone to produce anthocyanins at the seedling,bolting and maturity stage,showing purple at different parts of the plant,whereas,the wild type had no such kind of phenotype.The protein expression profiles of the mutant and the wild type seedling leaves under natural growth conditions were analyzed through proteomics approach.Thirty two differential protein spots that exhibited at least 1.5 fold in both materials were obtained.These differential proteins were involved in anthocyanin synthesis and the response of plants to abiotic and biotic stresses such as cold,salt,water,heavy metal ion and pathogen infection etc.According to the results of mass spectrometry analysis,the response of the mutants to waterlogging stress and Sclerotinia sclerotiorum infection was studied.The results showed that anthocyanin-susceptible mutant as appeared purple phenotype and anthocyanin synthesis of the mutant was earlier than the wild type.Transcriptome sequencing analysis of seedling leaves at 8th day after waterlogging for 24 h at the germination stage showed that the differential genes were related to plant hypersensitivity response,kinase activity,signal transduction and energy metabolism.At seedling stage,the relevant physiological indicator of the wild type and the mutant fresh leaves at 12 th day of waterlogging time were detected,the results showed that the mutants had less chlorophyll content,more anthocyanin and malondialdehyde content than the wild type and their soluble sugar and soluble protein contents were also slightly different.In addition,the experiments of resistance to Sclerotinia at seedling stage showed the mycelia of S.sclerotiorum invading the leaves ofanthocyanin-susceptible mutant as slowly grew and were confined to the vicinity of the inoculation site,and the cell damage or cell death of the mutant leaves was significantly lighter than that of the wild type.This indicates that mutants were resistant to S.sclerotiorum infection.These results provided the evidences for cloning the mutant gene and studying the molecular mechanism of mutation.