| The leaf length and grain shape of maize are important agronomic traits c losely related to agricultural production.There are abundant natural variations i n different varieties of materials,but the corresponding quantitative trait genes are currently not fully understood.In the previous study,the parents Zheng58and Chang7-2 of the maize inbred were used as parent materials to construct t he F2generation hybrid population,and the 2567 individual plants in the F2g eneration population were subjected to the second generation high-throughput g enome reconstruction.Sequencing and combined with phenotypic statistics,and running a large of genetic analysis,we found that a novel QTL locus（Liu et al.,2019）that regulates the lower leaf length of maize localized at the positio n of 169Mb on chromosome 7.The candidate genes were choosed and combin ed with this region.According to the genome sequence information of Zheng58 and Chang7-2,we judged that the gene affecting this locus is Zm LNG1（Zm0001d022072）.It was confirmed by RACE that the size of the Zm LNG1 Transc ript under the background of Chang7-2 and Zheng58 was different.And the fr agment obtained by 3’RACE of the Zm LNG1 gene under the background of C hang7-2 was larger than the fragment obtained by amplification under the back ground of Zheng58.Through the analysis of the background of Zheng58 and t he anaylysis of the DNA sequence of the corresponding regions of Zheng58 a nd Chang7-2,it is found that a large of fragments are missing in the Zm LNG1region in the background of Chang7-2.It is possible that the fusion of the ca rboxyl end of the Zm LNG1 region in the background of Chang7-2 generated a new protein.In order to confirm the function of the Zm LNG1 allele in the Z heng58 and Chang7-2 background,we constructed a vector that overexpressed t he corresponding Zm LNG1 protein and transferred it into the maize inbred line B104 by genetic transformation technology.The transgenic results revealed that the Zm LNG1 protein under the Chang7-2 background didn’t have normal func tions,and the Zm LNG1 protein was over-expressed in the B104 material.Cam pared with the B104,The Zm LNG1 transgenic material in the Zheng58 backgro und showed elongation of leaves,thinner ears,the decrease in the number of r ows,the average number of grains in row changes in corn grain shape,The c orn heights becames more high.The Zm LNG1 is involved in regulation mecha nism of Zm LNG1,we confirmed by subcellular localization experiments that Z m LNG1 protein is located in the cytoskeleton under Zheng58 and Chang7-2 ba ckground.The functional difference of alleles in the two backgrounds is not ca used by thediscrepancy of in the protein localization.Through literature review,we found the homologous proteins in tomato,Arabidopsis,rice and other spec ies found that LNG1 can interact with TON1 protein and OFP protein family.Hence,we confirmed the interaction between Zm LNG1 under the background Z58 and chang7-2 by yeast two-hybrid experiments.The results show that Zm LNG1 protein can interact with Zm TON1 and Zm OFPs under the background of Z58,and Zm LNG1 protein can interact with Zm OFPs under the background of Chang7-2,but Zm TON1 cannot interact with Zm LNG1 under the backgrou nd of Chang7-2.The results of the LUC luciferase experiment are also consist ent with the results of the yeast two hybrid experiment,indicating that the car boxy terminalstructure of the Zm LNG1 protein is essential for its function and can bind TON1 protein.Therefore,How Zm TON1 affects the protein function of Zm LNG1?The function of the Zm LNG1 complex will require further discu ssion and exploration. |
