Characteristics And Genetic Identification Of Plant Type Mutant ZPR1of Arabidopsis

The modification of plant architecture plays a major role in breeding high yield of vegetables by establishing productive crop community. Arabidopsis thaliana was classified to Brassicae, Cruciferae, which is closely related to Brassica rapa, Brassica oleracea, Brassica juncea oilseed rape, showing highly similarity in genome. Here a novel mutant zpr1in Arabidopsis was screened and identified. In order to provide reference for vegetable architecture improvement, the phenotypic characteristics and molecular mechanism of the Arabidopsis mutant line zpr1were studied.Mutant zpr1is a recessive T-DNA insertion line and was investigated in phenotypic characteristics, hormone responses, light treatments, and genetic analysis. The gene was cloned and expressed in plant, as well as heredity resistance screening and bioinformatics analysis. The main results were as follows:(1) According to the observation of the phenotypic characters, comparing to the wild type Ws-2, the stem branch number of mutant line zprl was increased near terminal inflorescence. The stem leaves of mutant line zprl were lanceolate leaves different from the obovate leaves of wild-type. The other phenotypic characters such as the height of main inflorescence, plant height, branch height, and branch length in mutant zpr1were higher than those in wild type, and the branch number and silique number were also higher. But the seed weight of zpr1was less than wild type.(2) Plasmid rescue and IPCR identified the position of mutant gene in the genome and showed that the insertion of T-DNA fragment in the promoter region of ZPR1abolished its expression.(3) The experiments on hormone and light response indicated that the mutant zpr1was different from Ws-2in hormone sensitivity and light sensitivity.(4) The study on protein subcellular localization showed that ZPR1protein mainly localized in cell membrane, occasionally localized in parts of cell membrane, cytoplasm and the nucleus.(5) The ZPR1overexpression lines were found that the leaves were dark green, curly, growth retardation, but the knockdown lines were similar to mutant line zprl. The phenotype of mutant line zprl was further confirmed by the knockdown of ZPR1gene.(6) Analysis of the cis-acting element of transcriptional regulatory region identified multiple regulatory elements. Bioinformatic analysis discovered that Arabidopsis ZPR1gene which encoded a protein containing a-helix, β-fold, and random coil was closely related to cucumber ZPR1.It revealed that the expression of ZPR1has regulatory effects in the plant architecture development and the expression level will regulate the hormone sensitivity and light sensitivity. Eventually, this gene leads to the formation of plant architecture.