The Analyses Of PIN3of Capsella Bursa-pastoris And Its Influence To Carpel Morphogenesis

The different growth patterns build the various phenotypes of plants. The auxin and its polar transport is important for tissue morphogenesis and it is the main factor determines the growth patterns. The Arabidopsis thaliana and Capsella bursa-pastoris are both the herb plants belong to the same generic Cruciferae. But the carpel’s shape is quite different that the Arabidopsis thaliana is in cylindrical and heart-shaped of Capsella bursa-pastoris. In order to reveal the difference in carpel morphogenesis of the two weeds that we probe an auxin polar transport difference in the two carpels.The PIN3is the key gene involves in auxin polar transport, in order to explore its function in carpel morphogenesis, we cloned the1488bp upstream sequence of the PIN3gene in Capsella bursa-pastoris by chromosome walking method. The bioinformatic analysis recognized that the sequence contained TATA-box、 CAAT-box which is typically in eukaryote promoter elements and with the light responsive element, cis-acting regulatory element involved in the salicylic acid responsiveness, cis-acting regulatory element involved in anaerobic induction, ds-acting regulatory element involved in high level expression of endosperm etc. The phylogenies comparison of the two promoter sequence of the PIN3gene in Arabidopsis and Capsella showed that they share82%homology. By the analysis of online software for plant promoter that we find these two promoters had partial common light responsive element and other different light responsive element. There are also different cis-acting regulatory elements involved in abiotic stress response in the two promoters. It is may just because of these differentiated elements with in the promoter that the PIN3gene expression is in different model in Arabidopsis and Capsella that lead to the different characteristic of auxin polar transport and determine the different morphogenesis in carpel in the two plants.To validated the differentially expressed of promoter, we constructed a CbPIN3pro::GUS vector by GUS report gene and transformed the Arabidopsis. But we didn’t get the transgenic plants so far.We constructed a plant expression vector pBI121::CbPIN3by Capsella PIN3gene cDNA and its promoter. The recombinant is then transformed into Arabidopsis by Agrobacterium-mediated inflorescence infiltration and finally we got two transgenic Arabidopsis plants by selected of antibiotics and molecular detection which had similar phenotype. The plant morphology and carpel’s shape of transgenic Arabidopsis had great changes which displayed the typical phenotype of auxin interference. Although the transgenic carpel is still held the cylindrical growth, but the longitudinal length got shorter in different extent and the average length is0.27times of it is in the wild type. The transgenic plants are growing weak than the wild type as a whole. We predicate that the CbPIN3gene expression in the transgenic arabidopsis interferes the auxin normal distribution in the carpel and affects its normal growth by decrease the capability of longitudinal auxin polar transport in the carpel that leads to shorten carpel.