Functional Analysis Of Ethylene Response Factor Gene CmERFI-5、CmERFI-13、CmERFI-15 During Fruit Development In Melon

The function of ethylene response factor gene CmERFI-5、 CmERFI-13、CmERFI-15 were studied from fruit of melon cv. Hetao. ERF gene was downstream component of ethylene signal transduction pathway, the fruit development was regulated through assoiciation with cis element GCC-box of upstream target genes. CmERFI-5、CmERFI-13 and CmERFI-15 gene cDNA were cloned from melon(Cucumis melo L.) by RT-PCR method. The full-lenth of the cloned gene cDNA,which were 934 bp、879 bp and 769 bp respectively, and the open reading frame were 732 bp、834 bp、636 bp respectively,243、277、 211 amino acids were encoded. The overexpression and RNAi vector 2of the target gene were injected into the mature green fruits of melon by transient expression of Agrobacterium method after constructed the overexpression vector and RNAi vector respectively, and the injection sites were observed. The injection site of fruit emerged green (delayed maturation) phenotype after inject the both of overexpression and RNAi interference vector of CmERFI-5 gene. The injection site of fruit emerged yellow after inject overexpression of CmERFI-13 gene vector, and emerged green after inject RNAi interference vector. The injection site of fruit emerged green and yellow after inject vector of overexpression and RNAi interference of CmERFI-15 gene respectively. Molecular detection result showed that, the expression of the target gene of the injection site was increased compared with control after the injection of overexpression vector of CmERFI-5, CmERFI-13 and CmERFI-15 gene, which indicated that exogenous introduced gene was expressed; the expression of the target gene was decreased compared with control after the injection of RNAi vector, which indicated that expression of the endogenous gene was successfully suppressed. qRT-PCR result of gene related to fruit ripening showed that,CmERFI-5 has no regulation effect, CmERFI-13 gene showed positive regulatory effect on CmACO1, CmACS1, CmADH2 and CmCCDl genes. CmERFI-15 gene exerted the negative regulation on CmACO1 and CmACS1 genes. In conclusion, CmERFI-5 gene performed no function during melon fruit maturation, CmERFI-13 gene may promote fruit ripening and CmERFI-15 gene showed the function of delay maturity.