Cloning and Functional Analysis of LtMYB305 in Liriodendron tulipifera
[Objective]MYB305 as a member of the MYB R2R3 subfamily,plays an important role in plant nectary development,nectar protein expression,starch accumulation and hydrolysis,and flavonoid synthesis.Therefore,it is of great significance to study the expression profile and function of MYB305 for the molecular mechanism study of Liriodendron tulipifera floral nectary.[Method]Having floral nectary of nectariferous plant L.tulipifera as materials,the anthocyanidin content in five stages of floral nectary was detected by spectrophotometry,LtMYB305 gene was cloned via RACE(rapid-amplification of cDNA ends)technology,and relative expressions among different tissues were analyzed by RT-qPCR assay.Then,subcellular localization of LtMYB305 protein was verified using tobacco leaves as materials,and the function of LtMYB305 gene was studied by genetic transformation approaches of wild type Arabidopsis thaliana(col).[Result]The anthocyanidin in the nectaries of L.tulipifera was accumulated from the late expanding stage,increased sharply at the early flowering stage,and reached the highest of 27.14 μg/g at the withering stage,which was consistent with the process of nectar secretion and coloring.The full-length of LtMYB305 was 931 bp encoding 198 amino acids and its protein was hydrophilic and non-transmembrane.LtMYB305 was expressed highly only in the nectary of L.tulipifera at anthesis stage,and hardly in other tissues.LtMYB305 protein was localized in the nucleus.After the overexpression of LtMYB305,the nectary groove of the lateral nectary disappeared and deepened,the expressions of AtMYB30,AtPIN,AtSWEET9 genes related to flower nectary were up-regulated,and the expressions of AtCRC,AtBOP1/2,AtMYB21,AtSWEET3/4/7 genes were down-regulated.[Conclusion]The LtMYB305 has typical characteristics of transcription factor and is involved to the nectary development in L.tulipifera.
国家科技期刊平台
NSTL
万方数据
维普
