Cloning And Functional Analysis Of MdWUS Gene Of Apple

WUSCHEL—related homeobox(WOX)is a special kind of HB transcription factor in plants.It participates in many growth and development processes of plants,and WUSCHEL(WUS)gene is a member of WOX family.Reports from Arabidopsis thaliana suggest that WUS can promote plant regeneration.The low regeneration efficiency of apples leads to low genetic transformation efficiency of apples,which seriously interferes with the process of gene function identification of apples.The function of WUS in Apple has not been reported yet.In this study,the full-length coding region sequence of gene was cloned,and the overexpression vector was constructed to obtain plants overexpressing mdus gene and identify the function of mdus gene.The main results of this study are summarized as follows:1.The coding sequence of MdWUS gene was successfully cloned from the cDNA of' GL-3'apple by using PCR technology.The total length of the sequence is 981 bp,encoding 326 amino acids.Compared with other WUS genes of Rosaceae,they all have conserved HD domains.Further,through evolutionary analysis,it is found that MdWUS in apple and WUS gene in Rosaceae pear have the closest genetic and evolutionary relationship.2.Through the analysis of the spatio-temporal expression of' Hanfu' and GL-3,it was found that the MdWUS gene in apple had higher expression in stem tip and young leaves,and lower expression in root and fruit.3.transcriptional activation test and subcellular localization test prove that MdWUS is a nuclear localization protein with transcriptional activation activity.4.pRI-MdWUS overexpression vector was constructed and transformed into GL-3 apple by Agrobacterium tumefaciens.Four transgenic lines were obtained.Observation and analysis showed that overexpression of MDWIS has the functions of improving apple leaf regeneration efficiency and promoting bud tillering and lateral root formation.