Functional Study Of LGL/SRO7/77/Tomosyn Family Genes Attyn11/12in Arabidopsis Thaliana

Vesicle trafficking is one of the basic events in eukaryotic cells. It is the major pattern to maintain the exchange of materials and communication of information among organelles. In plant, vesicle trafficking is involved in the process of stress response, which provide a novel approach to study the stress resistance.According to the existed reports, Lgl/Sro7/77/Tomosyn was involved in protein polarization and polarized vesicle trafficking. The family contains SNARE-related domains. Sro7p/77p and Tomosyn can combine with t-SNARE proteins, regulating the assembly of SNARE complex and finally accelerating or blocking the vesicle fusion. In terms of secretory vesicle trafficking, Sro7p/77p not only had part of overlapped function with Exocyst complex, but also participated in the abiotic stress response. In recent years, SNAREs was reported as an essential factor to response stress environment. Therefore, Lgl/Sro7/77/Tomosyn might participate in the stress response by considering the similar structure and interaction with SNAREs.Our study principally concentrates on the function of homologous genes of Lgl/Sro7/77/Tomosyn family in Arabidopsis thaliana, which were named as AtTyn11(At5g05570) and AtTyn12(At4g35560). They were classified as R-SNARE Tomosyn-like protein in the report, but it did not mention the detailed function.By the analysis of amino acid sequence and forecast of conservative domain via the professional websites and software, we found that AtTyn11/12had similar structure with Lgl/Sro7/77/Tomosyn family, implying that they might also share the similar function.Referring to the microarray information and applying various molecular and biochemical technologies, we identified the preliminary function of AtTyn11/12. The conclusions were summarized as follows: 1. AtTyn11and AtTyn12might share the overlapped function:As the microarray information and expression profiling indicated, AtTyn11nd AtTyn12expressed in some common sites in despite of some distinct sites.2. AtTynl2might be involved in abiotic stress response in Arabidopsis thaliana:Our data showed that expression of AtTyn12upregulated under the treatment of NaCl, drought, mannitol and ABA in WT (wild type) plants, which was in accord with the microarray information. In AtTynl2promoter::GUS transgenic plants, the expression of AtTyn12also upregulated under the treatment of NaCl.3. In normal situation, the tyn12-1and tyn12-2T-DNA insertion lines did not present the growth defection, which might be because of deletion of AtTynl2having not obvious defection in normal growth environment or redundant function between AtTynll and AtTyn12.4. Under the treatment of NaCl, the root length of tyn12T-DNA mutant lines were longer than of WT, but the difference not significant. Besides, the difference of germination rate was also not significant. The reason might be due to the redundant function between AtTynll and AtTynl2.There was not the related report about the function of Lg1/Sro7/77/Tomosyn family in plant. However, our study indicated that the structure was conservative between AtTyn11/12and Lgl/Sro7/77/Tomosyn family. Moreover, AtTyn12might participate in the abiotic stress response in Arabidopsis thaliana, which could be regarded as the preliminary indication of the function similarity between AtTyn11/12and Lg1/Sro7/77/Tomosyn family.Our study linked the vesicle trafficking pathway and stress response, providing a novel approach to explore for the stress resistance of plant. The further research needs to be done. Some ideas have been launching in the laboratory. For example, gaining the AtTynll/12dual deletion line and35S::AtTyn11/12cDNA::GFP overexpression line.