Screening And Identification Of Proteins Interacting With Kernel Number Per Row-associated Protein（ZmSTKR）of Maize

The kernel number on the maize ear is determined by the differentiated floret number.The actual kernel number per ear is determined by the number of floret normally be pollinated.The initiation and maintenance of various meristems during the female inflorescence development will affect the number of female florets and ultimately affect kernel numbers.Therefore, the genes that control initiation and maintenance of various meristems may be closely related with the formation of kernel number. In previous study, our team have obtained a gene which is considered as a candidate for kernel number per row of maize andis designed as ZmSTKR. In the study, the proteins interacting with ZmSTKR were screened and identifedby the yeast two-hybrid system, and were then validated by Bimolecular Fluorescent Complementary(BiFC) in vivo.the domain structurein ZmSTKR was detected byyeast two-hybrid using progressively truncated protein. Our objective is to detect proteins interacting with ZmSTKR in order to lay a sound foundation for analysis of gene function and acting mechanism of ZmSTKR. The main results are as follows:1. Taking ZmSTKR as bait protein, we screenedyeast-two hybrid library and finally obtained 105 available sequences after the analysis of sequences. There are 20 gene sequences that encodetransmembrane transport-associated proteins accounting for 19 percent of the total available sequences. ribosomal proteins(2large subunit proteins,16 small subunit proteins) and heat shock proteins have obtained 18 and 15 gene sequences accounting for 17.1 percent and 14.3percent of the total respectively; We found some sequencesencoding kinase and phosphatase which have 4 and 2 sequences respectively. In addition,we also found 3 sequences encoding ubiquitin ligase. We obtained 64 UniGene removing redundant sequences.2. On the basis of the hypothesis that ZmSTKRmay be a candidate for maize kernel number per row, we chose some proteins which function in maize inflorescence development preferentially to carry out yeast-two hybrid. These proteins include TE1,LG2,zmPIN1, FEA2, BIF2, TB1,BD1, BA1, DLF1, KN1. Yeast- two hybird revealed that LG2 and TB1 existinteraction with ZmSTKR. The interaction verification of other proteins screened by cDNA library screen is in the works.3. Bimolecular Fluorescent Complementary revealed the ZmSTKR protein interacted with LG2 in arabidopsis protoplast, Inyeast-two hybrid, the false positive of TB1 results from autonomous activation.4. Yeast-two hybrid using progressively truncated ZmSTKR proteinshowed that all of truncated proteins didn’t interact with LG2, andindicating the complete protein structure of ZmSTKR is necessary to ensure the effective interaction between ZmSTKRand LG2.