拟南芥miR156与miR399在低磷胁迫中的对话机制初探

Initial Exploration of Cross Talk between miR156 and miR399 of Arabidopsis thaliana under Low Phosphorus Stress

为了进一步研究miR156与miR399在低磷响应过程中是否存在对话机制,采用杂交方法,将35S:MIM156(miR156功能降低拟南芥植株)与miR399f(miR399f超表达拟南芥植株)杂交获得杂交转基因植株35S:MIM156miR399f。采用原位显色法和根际酸化能力测定法,研究低磷胁迫下35S:MIM156、miR399f及35S:MIM156miR399f植株根际酸化情况,并测定其花青素和无机磷含量。结果表明,35S:MIM156植株的花青素含量较野生型(WT)植株显著降低,miR399f、35S:MIM156miR399f植株与WT无显著差异;35S:MIM156植株的酸化能力较WT显著降低,miR399f、35S:MIM156miR399f植株酸化能力均较WT显著增强;35S:MIM156、miR399f、35S:MIM156miR399f植株的无机磷含量均较WT显著升高。综合分析,推测在低磷条件下miR399参与了miR156调控的花青素积累和根际酸化过程,miR156和miR399共同参与磷平衡过程。

In order to explore whether the cross talk between miR156 and miR399 exists,the 35S : MIM156 miR399f double hybrid transgenic plant was constructed by crossing between 35S : MIM156 (transgenic plant silencing miR156)and miR399f(transgenic plant overexpressing miR399f).The rhizosphere acidification phenotype,anthocyanin and inorganic phosphorus contents of 35S : MIM156 miR399f, 35S : MIM156 and miR399f plants were studied by the in-situ coloration method,rhizosphere acidification activity assay and so on.The results showed that compared with WT(wild type),the anthocyan content of 35S : MIM156 plants significantly decreased,the anthocyan contents of miR399f and 35S : MIM156 miR399f plants were not significantly different from WT;the rhizosphere acidification ability of 35S : MIM156 significantly decreased,the rhizosphere acidification abilities of the miR399f and 35S : MIM156 miR399f plants significantly increased;the inorganic phosphorus contents of 35S : MIM156 ,miR399f and 35S : MIM156 miR399f plants significantly increased.Overall,it was speculated that miR399 was involved in the process of anthocyanin accumulation and rhizosphere acidification processes regulated by miR156,and miR156 and miR399 both took part in phosphate homeostasis process under low phosphorus stress.