Preliminary Study On Three Highly Expressed Functional Unknown Genes In Muskmelon Fruit Development

Being a typical horticultural cash crop,muskmelon is an essential alternative model plant to tomatoes for fleshy fruit development research.In this study,Cucumis melo L.was used as the experimental subject,and some molecular biology techniques were used to investigate the characteristics of three function-unknown genes MELO3C015185,MELO3C020745 and MELO3C011405,as well as their functions during the fruit maturation process.The main results of this study are as follow:? Based on the transcriptome data of muskmelon fruit,three functional unknown genes were screened and identified.The gene IDs were MELO3C015185,MELO3C020745 and MELO3C011405,respectively.By bioinformatics analysis,it was found that MELO3C015185 protein was hydrophobic protein with a transmembrane domain and no signal peptide.Subcellular localization predicted that the protein was located on the cell membrane.MELO3C020745 protein and MELO3C011405 protein are hydrophobic and has no transmembrane domain and no signal peptide.Subcellular localization predicts that the MELO3C020745 protein is located in cytoplasm and the MELO3C011405 protein is located in the nucleus.? Real-time fluorescence quantitative PCR detection results showed that the expression level of MELO3C015185 gene was stem > leaf > male flower >growth period.The expression of MELO3C020745 gene was the highest in fruits during climate period,followed by in male flowers.The expression of MELO3C011405 gene was the highest in bisexual flowers and the second in fruits during ripening period.The results of subcellular localization showed that MELO3C015185,MELO3C020745 and MELO3C011405 proteins were located in cell membrane,cytoplasm and nucleus,respectively.? The cDNA of MELO3C015185,MELO3C020745 and MELO3C011405 genes were cloned and their ORFs were 777 bp,249 bp and 264 bp,respectively.Three overexpression vectors pP-5185,pP-0745,pP-1405 and gene editing vectors pYL-5185,pYL-0745,pYL-1405 were constructed respectively.? Overexpression vectors pP-5185,pP-0745,pP-1405 and editing vectors pYL-5185,pYL-0745,pYL-1405 were introduced into muskmelon by ovary injection.The T1 generation transformed seeds were detected by PCR.The positive rates were 8.3%,11.6%,15%,21.7%,16.7% and 10%,respectively.The T1 transformed seeds were sown in sunlight greenhouse,5 plants,4 plants,5 plants and 5 plants,4 plants and 4 plants were obtained respectively by PCR detection.By statistic analysis of the mature period of transgenic plants of positive T1 generation,we can see that the mature period of transgenic plants of MELO3C020745 gene overexpression vector is 2.7 days earlier than that of wild type control,while the mature period of transgenic plants of editing vector is 7.3 days later than that of wild type control.The maturity of the transformed plants with the other two genes MELO3C015185 gene and MELO3C011405 gene is almost the same as that of the wild-type control.Preliminary results show that MELO3C015185 gene and MELO3C011405 gene may not have any effect on fruit ripening,while MELO3C020745 gene plays a role in promoting fruit ripening.