The Exploration Of BrMYB80b Sense LncRNA In Regulation Of Fertility In Brassica Rapa

Pollen development is not only a key part of plant sexual reproduction,but also related to many aspects of agricultural production.To sexual reproduction of vegetables,pollen development determines the quality of seed quality.The commodity value of the vegetables with seeds and fruits as the main organ of the product is also dependent on pollen development.In breeding practice,pollen development is closely related to male sterility,self-incompatibility and other agronomic traits.Long non-coding RNA(IncRNA)is a type of RNA that has a non-coding potential and longer than 200 nt.Many studies have shown that IncRNA involved in plant growth and development regulation.In the previous study,RNA-seq was employed on the fifth-grade buds of ’Bcajh97-01A/B’,identifying a lncRNA-BrMYB80bSSLncRNA specifically expressed in male sterile line.The IncRNA is located in the locus of transcription factor BrMYB80b,and MYB80 is the key transcription factor during the tetrad stage of pollen development.In this paper,the function of BrMYB80bSSLncRNA in pollen development was investigated.First,the full length of BrMYB80bSSLncRNA was obtained by RACE(rapid-amplification of cDNA ends)technique,and its coding potential was analyzed.Then,it was transformed into Brassica rapa to explore its function in pollen development and its functional form was deduced.The main findings are as follows:(1)The specific expression of BrMYB80bSSLncRNA in the ’Bcajh97-01A’ line was verified by qRT.It was also verified that BrMYB80a and BrMYB80b were differentially expressed in’Bcajh97-01A/B’.(2)The full length of BrMYB80bSSLncRNA was obtained by RACE technique,and the transcripts of sense BrMYB80b locus were also discovered.The coding potentials of three newly discovered transcripts were analyzed.It was testified that BrMYB80bSSLncRNA was a sense IncRNA.(3)BrMYB80bSSLncRNA overexpressed in Brassica rapa,and four pollen apertures was found in BrMYB80bSSLncRNA overexpressing transgenic cabbage,but some overexpressed plants did not observe this phenomenon,suggesting that the expression level may not reach the threshold.In BrMYB80bSSLncRNA highest expression of individual plants,the statistics to about 15%of the pollen has four apertures.(4)In the BrMYB80bSSLncRNA overexpressing transgenic plants,the expression of BrMYB80b was increased,suggesting that BrMYB80bSSLncRNA may regulate the development of pollen germination trough by regulating the expression of BrMYB80b.(5)BrMYB80a and BrMYB80b genes were knocked out by CRISPR-cas9 technology,but the transgenic cabbage lacking BrMYB80a and BrMYB80b function was not obtained.It is inferred that the mutant is not efficient or ineffective in Chinese cabbage,and the related technology system has yet to be optimization.