Preliminary Functional Analysis Of F-box Family Gene At5g22700in Arabidopsis

Bioinformatics analysis showed that At5g22700belongs to F-box gene,contain a conserved F-box domain, FBD domains. Its promoter function wasprediction by plantCARE, there are a lot of light and auxin responseelements. However, its function is not clear at present. In this paper, F-boxfamily gene At5g22700function is analysised. The research results madethe following:Firstly, the fragme nt of full length and F-box domain of At5g22700were amplified by PCR, then investigate if At5g22700interacts with ASKproteins by using the yeast two-hybrid and colony-lift filter assay.It foundAt5g22700interacts with ASK4,indicting that At5g22700may form SCFcomplex.Then, the two overexpressing line At5g22700ox-1, At5g22700ox-2were obtained by using Gateway cloning, Agrobacterium mediated floral dip.Meanwhile, T-DNA insertion mutant Salk₀60937, Salk₀09942wereordered from TAIR and identified. Checking the expression of At5g22700invarious tissues of Arabidopsis, it found At5g22700expressed in all thetissues, and the expression level in flowers and roots are relatively higher,indicating that At5g22700may be involve in root and flower development.Further, the function of At5g22700gene in the light signal pathwaywas analysis. It was found the expression level up-regulation under bluelight, down-regulation under red and no effect under far-red light. Rootlength was observed in different light, it found that the overexpression lineroot longer than wild-type plants under blue light. Analysis of changes indifferent light intensity, it found the intensity is more strong, thedifference between the overexpression plants and the wild type main isgreater, indicating that it may exist specific response to blue light. TheT-DNA mutant was no difference comp are with wild-type under any light, itsuggests that there may be functional redundancy phenomenon.Finally, the function of At5g22700gene in auxin signaling pathwaywas analysis. With the increasing concentration of auxin, theoverexpression plants were more sensitive than the wild type, the weaker light intensity, the more obvious inhibition. Using NPA, overexpressionline was sensitive than wild-type plants, inhibition percent wassignificantly larger than the wild type. Expression level of PIN1andPIN2were identified in the mutant plants, it foundoverexpression plants decreased significantly, while the T-DNAmutant higher than wild type. At the same time, auxinbiosynthesis related YUC family genes was analysis, the expression ofYUC gene family was reduced in overexpressing plants, and nosignificant change in the deletion mutants, it indicated At5g22700may bea positive regulator of auxin signal transduction pathway, inhibition ofpolar auxin transport and synthesis by feedback.