Effects Of Enhanced UV-B Radiation And He-Ne Laser Irradiation On MAP65-1of Arabidopsis Thaliana Leaves

With the continuous progress of human society, the rapiddevelopment of industrialization, the human impact on nature isbecoming more frequent, while the atmospheric environment hascaused serious damage. A large number of pollutants such as CFCs,chlorine, sulfur, NO and N02, etc. are not addressed discharged intothe atmosphere, causing some damage to the ozone layer, leadingto the surface of the ultraviolet radiation and the trend hascontinued to improve its affect plant metabolism, growth andviability of the plant therefore caused some damage. Laser as a newlight source, appropriate doses of He-Ne laser may have to promoteplant growth and metabolism, and is UV-B on plant damage causedby a certain repair.The microtubule binding protein MAP65is a “midzone MAP”,essential for the integrity of the anaphase and cell division. In thisstudy ecotype Columbia (Columbia-0) wild-type Arabidopsis as experimental material, set the four treatment groups, the controlgroup (CK), He-Ne laser (5mW·mm-2) exposure group (L), enhancedUV-B (15.55kJ·m-2·d-1) radiation group (B), and a composite of bothirradiated groups (BL), to study He-Ne laser and enhanced UV-Bradiation on Arabidopsis microtubule binding protein MAP65-1effects from physiological, cellular and molecular level. The mainsteps has the following aspects:(1) Determination of the optimaldose of He-Ne laser and UV-B on Arabidopsis through physiologicaland biochemical indexes Arabidopsis seedlings.(2) Analysis of theeffect of He-Ne laser and enhanced UV-B radiation on Arabidopsismicrotubule binding protein MAP65-1and tubulin effects bySDS-PAGE electrophoresis and Western blot.(3) By using indirectimmunofluorescence staining and confocal laser scanningmicroscopy system for normal processing group MAP65-1anddouble-labeled microtubules explore the somatic cells MAP65-1with the correlation between the distribution of microtubules andstudied enhanced UV-B radiation MAP65-1changes in thedistribution.(4) Using the PCR detection of He-Ne Laser andenhanced UV-B radiation on Arabidopsis MAP65-1gene expression.Comprehensive analysis of the He-Ne Laser and Enhanced UV-Bradiation on MAP65-1, and to explore microtubule binding proteinchanges after radiation for research in wheat research group enhanced UV-B radiation after the "fractional division" provides atheoretical basis.The results showed that:1. The appropriate dose of He-Ne laser irradiation can promotethe growth of Arabidopsis seedlings, and the optimal radiation doseis5mW·mm2,3min every day. When the irradiation time is longerthan3min, the promoting effect on seedling becomes smaller, andwith the irradiation time prolong even showed suppression;Arabidopsis continuous UV-B radiation nine days at a dose of15.55kJ·m-2· d-1, screened daily radiation time should be90min,radiation longer than90min, Arabidopsis seedlings of variousantioxidant enzymes activity declined sharply, seedlings tend todie.2. By Coomassie blue staining and SDS-PAGE electrophoresisand immunoblotting identification analysis found that themicrotubule depolymerization after UV-B radiation; In the He-Nelaser and UV-B complex treatment, the degree of microtubuledepolymerization decreased; After He-Ne laser treatment, themicrotubule polymerization. So that He-Ne laser to some extentalleviated the depolymerization of microtubule after UV-B. Thecontent of MAP65decreased in B group, the content of MAP65in BLgroup is still lower than the control group, but higher than B group,MAP65protein content increased in L group. The content of microtubule binding protein MAP65-1in the UV-B radiation aftergradation analysis,in the BL group, the content of MAP65-1markedly increased, the content of MAP65-1increased slightly in Lgroup.3. Indirect immunofluorescence staining and confocal laserscanning microscopy system scan showed that MAP65-1co-localization with microtubule in Arabidopsis protoplasts; AfterUV-B radiation, the positioning of MAP65-1in cytoplasm changes,and mainly clustered around the membrane of cell.4. Analysis the expression of MAP65-1gene expression by PCR,the results showed that: compared with the control group,enhanced UV-B radiation, the Arabidopsis MAP65-1geneexpression increased; while the combined treatment groupsArabidopsis MAP65-1gene expression decreased, but still higherthan the B group; After He-Ne laser treatment alone, compared withthe control MAP65-1gene expression decreased.