Tomato Mitochondrial Transcription Termination Factor (mTERF) Whole Genome Identification And Research On The Function Of Resistance Related Genes

The mitochondrial transcription termination factor family(mTERF)is a class of highly conserved DNA-binding proteins that exist in multicellular organisms and are gene expression regulators with a similar leucine zipper structure.mTERF plays an important regulatory role on the function of mitochondrial genes,participates in the regulation of mitochondrial gene replication,transcription and translation,and plays an important regulatory role in biological evolution,plant growth and development,and abiotic stress.There have been some studies on the mTERF gene family of plants,such as corn,grapes,peppers,but the study on the mTERF gene family of tomato has not been reported yet.In this experiment,we screened and identified stress resistance genes in the tomato mTERF gene family by genome-wide mining and bioinformatics analysis,and performed functional verification of some genes with significant stress resistance responses.The results provide a theoretical basis for further elucidating the role of mTERF gene in the regulation of tomato stress response.The results of the study are as follows:1.The genome-wide identification of tomato mTERF gene family was carried out by bioinformatics analysis,and it was found that there were 28 mTERF genes in tomato.After phylogenetic analysis and chromosomal location analysis,it was found that the tomato mTERF gene family was divided into 6 groups and distributed on 8 different chromosomes.Analysis of the cis-acting elements of the tomato mTERF gene family revealed a large number of cis-acting elements related to plant hormone regulation and abiotic stress response,and a few cis-acting elements related to circadian rhythm control and regulation of light response.2.Under low temperature,drought and high salt stress treatments,most of the tomato mTERF genes responded to more than one stress response.After screening,it was found that 6 genes responded to drought stress,10 genes responded to cold stress,4 genes responded to salt stress,and 2 genes responded to salt stress.The genes respond to drought,low temperature and high salt stress simultaneously.Tissue-specific expression analysis showed that the selected 15 different subgroup genes had different expression levels in different tissues,and the same gene had different expression levels in the same tissue.3.The screened SLmTERF13,SLmTERF21,and SLmTERF23 genes that were significantly up-regulated under drought and salt stress were functionally verified.It was found that the silencing of SLm TERF13,SLmTERF21,and SLm TERF23 reduced the drought resistance of tomato plants to different degrees,and the silencing of SLmTERF13 and SLmTERF21 reduced the salt tolerance of tomato.4.The subcellular localization of two genes SLmTERF13 and SLmTERF21 with obvious anti-counterregulatory effects found that both genes were located in the nucleus.The gene SLmTERF21 with the most obvious anti-stress response regulation effect was overexpressed and constructed to obtain T0 generation plants.Compared with the wild-type control plants,the plants overexpressing the SLmTERF21 gene grew faster and had more collateral leaves.