Identification And Expression Analysis Of FveD27 Gene In Woodland Strawberry

For the perennial herbaceous strawberry,the development of new stem branching is an important biological process,which is regulated by various complex factors such as genetics,environment and hormones.It is known that the novel plant hormone strigolactone is a key factor regulating the branch development of plants,but the role of strigolactone in the growth and development of strawberry is still unclear.In this experiment,we cloned the DWARF27(D27)coding region of the key gene for the synthesis of strigolactone from woodland strawberry ‘Yellow Wonder'.GFP was used to make a subcellular localization of Fve D27.The promoter of Fve D27 gene and GUS fusion expression vector were constructed and the expression of Fve D27 gene was revealed by GUS activity analysis,and its function was explored by phenotypic analysis of the Fve D27 gene overexpressing plants.The main results are as follows:1.The Fve D27 gene sequence was cloned from the woodland strawberry resource‘Yellow Wonder' by RT-PCR.The gene coding region was 789 bp in length.This sequence is identical to the sequence in the transcriptome data of the subject group,but is 3 bp less than the Fve D27 gene sequence in the NCBI database.2.The pRI101-Fve D27-e GFP fusion vector was constructed,and the subcellular localization method of tobacco indicated that Fve D27 was localized in the chloroplast.3.Quantitative analysis of the organ-specific expression in strawberry Fve D27 gene was performed by q RT-PCR,which showed that the expression level was higher in the new leaves and shoot tips,followed by petiole and old leaves,and the lowest expression in roots.A primer for the promoter of the Fve D27 gene was designed based on the woodland strawberry genome sequence,and a 1670 bp promoter was cloned by PCR.The pRI201-Fve D27-GUS fusion expression vector was constructed and transformed into forest strawberry 'Ruegen'.The GUS activity analysis of the transgenic plants showed that the blue color was expressed in the young leaves and stem apices of the transgenic plants.A small amount of expression was observed in the petiole and mature leaves,which was consistent with the q RT-PCR results.4.The overexpression vector of Fve D27 gene was constructed,and ‘Yellow Wonder'was genetically transformed to obtain 7 transgenic lines of strawberry overexpressing Fve D27 by Agrobacterium-mediated method.Phenotypic survey results showed that Fve D27 has a significant function of inhibiting tillering,and also has a regulatory effect on stem diameter,flowering time,and number of inflorescence.The results of this study provide new ideas for regulating the number of new stem branches,flowering period and increasing yield.