Screening Of Key TCP Transcription Factors Involved In Tomato Leaf Shape Development And Function Analysis Of SlTCP24

Leaf shape is an important biological shape for evaluating population yield ability,and leaf improvement is an important goal of plant type breeding.The change of leaf shape usually affects the physiological functions of plants such as photosynthesis,transpiration and stress resistance,and then affects the growth and development of plants.TEOSINTE BRANCHED1/CYCLOIDEA/PROLIFERATING CELL FACTORS(TCP)transcription factor is a kind of transcription factor unique to plants,which plays an important role in the growth and development of plants.The purpose of this study is to screen the influence of SlTCP24,a tomato transcription factor TCP family,which plays an important role in regulating tomato leaf morphology,on tomato leaf development;At the same time,the regulatory network of the influence of TCP transcription factor on tomato leaf morphological development was explored by using transgenic technology and molecular biology.The main results are as follows:1、According to the expression level of TCP in leaf development,and screened out 10 TCP family members related to leaf blades development process,including SlTCP2,SlTCP4,SlTCP8,SlTCP11,SlTCP14,SlTCP15,SlTCP19,SlTCP22,SlTCP24,SlTCP25,Then bioinformatic analysis was performed on them.The results indicated that these 10 SlTCP members were distributed in 8 different chromosomal locations.There were relatively larger differences in their length of basic group,amino acid and molecular weight.And all of the TCPs were unstable hydrophilic proteins.Analysis of SITCPs protein structure and element indicated that in center about 50 aa length amino acid sequences were relatively well conserved.Moreover,serine took relatively larger proportion.The site prediction of SlTCPs protein subcellular fraction were all localized on the nucleus.The above mentioned SlTCPs protein all contained the conserved domains of typical TCP family.Its classification of conserved motif was consistent with the branching of phylogenetic tree.2、 Using typical tomato leaf shape mutant materials LA2922 and LA2532 and their corresponding wild types,this experiment conducted q RT-PCR.The results indicated that the expression levels of SlTCP2,SlTCP11,SlTCP14,SlTCP15,SlTCP19 and SlTCP24 in leaf blades of LA2922 and LA2532 were in the opposit direction.SlTCP24 was highly expressed in mesophyll cells,and showed a dynamic expression of first decreasing,then increasing and then decreasing during the development of leaves.3、Through subcellular localization,it was found that SlTCP24 protein was localized in the nucleus,and has transcriptional activation activity.4、Ten transgenic plants of SlTCP24 overexpression were obtained by tomato genetic transformation.Compared with wild-type tomato,the leaves of 60-day OE-SlTCP24 tomato showed grow more a pair of laterool leaflet and several brain lobes.Compared with wild-type tomato,the leaves of 90-day OE-SlTCP24 tomato showed the leaves wrinkle and bend downward,and leaves crack deeper.Use VIGS technology to obtain SlTCP24 instant silence tomato,p TRV2-SlTCP24 is 60-day leaves have no brain lobes,the laterool leaflet is the same as that of wild type and there are two pairs,there is no obvious wrinkle and leaf crack in the leaves.4、The mesophyll cells of OE-SlTCP24 tomato are larger than those of wild-type tomato.In addition,the number of chloroplasts,chlorophyll value and photosynthetic rate in OE-SlTCP24 tomato leaves decreased.Compared with the control,the mesophyll cell area of p TRV2-SlTCP24 tomato was smaller.Although the chlorophyll value in the leaves decreased,the number of chloroplasts per unit area of the leaves increased and the photosynthetic rate increased.