The Function And Evolution Of Arabidopsis Thaliana AtD14 And AtDLK2

Strigolactone as a new type of plant hormones,it can interact with protein D14 and MAX2,then degrade D53 protein--the inhibitor of strigolactone.But whether D14 has the same function with MAX2,and what's the function of DLK2--D14 high homologous protein,the answer is unknown.We design experiments to reveal DLK2 and D14 function on the drought stress,salt stress and osmotic stress,in order to observe the germination rate and root length,found that D14 and DLK2 gene do not involved in the response of germination rate and root length.The DLK2pro:GUS/dlk2-3 is stained by GUS dyeing from seed to seedling,DLK2 gene is not express in the endosperm,but express on the coat of seed in globular stage.The expression of DLK2 gene in root on drought stress is from strong to weak,and can't be recovered when stress relieve.The expression in hypocotyl near the root is weaker as time pass by,and its expression would be a little recovered when stress relieve.The DLK2 gene expression in leaves is stronger than in root;Under high concentration of salicylic acid,DLK2 gene expression was strengthened,it indicates that DLK2 gene is regulated by high concentration salicylic acid;and on the hydrogen peroxide treatment,the expression at sixth hour is much stronger than the time point of third and twelveth hour,it shows that hydrogen peroxide induced DLK2 strongest at sixth hour.Abscisic acid involved in almost all abiotic stress in the plant,So we set up different concentrations of abscisic acid,found that when the abscisic acid concentration higher than 4 ?M,the total leaf and root length of dlk2 mutant were significantly higher than that of contrast,showing that abscisic acid has a negative effect to DLK2 gene.Low N treatment make Col-0 and mutant dlk2-3 the firstly branch number reduced,and max2-2 and d14 mutants' rossete development restrained.