MicroRNA395 mediates regulation of sulfate accumulation and allocation in Arabidopsis thaliana.
Sulfur is a macronutrient that is necessary for plant growth and development. Sulfate, a major source of sulfur, is taken up by plant roots and transported into various tissues for assimilation. During sulfate limitation, expression of miR395 is significantly up-regulated. miR395 targets two families of genes, ATP sulfurylases (encoded by APS genes) and sulfate transporter 2;1 (SULTR2;1, also called AST68), both of which are involved in the sulfate metabolism pathway. Their transcripts are suppressed strongly in miR395-over-expressing transgenic Arabidopsis, which over-accumulates sulfate in the shoot but not in the root. APS1 knockdown mutants accumulate twice as much sulfate as the wild-type. By constructing APS4-RNAi transgenic plants, we found that silencing the APS4 gene also results in over-accumulation of sulfate. Even though miR395-over-expressing transgenic plants over-accumulate sulfate in the shoot, they display sulfur deficiency symptoms. Additionally, the distribution of sulfate from older to younger leaves is impaired in miR395-over-expressing plants, similar to a SULTR2;1 loss-of-function mutant. The aps1-1 sultr2;1 APS4-RNAi triply repressed mutants phenocopied miR395-over-expressing plants. Our research showed that miR395 is involved in the regulation of sulfate accumulation and allocation by targeting APS genes and SULTR2;1, respectively.
Liang
Gang
G
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
Yang
Fengxi
F
Yu
Diqiu
D
D027321:Anion Transport Proteins / Q000378:metabolism; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D035683:MicroRNAs / Q000378:metabolism*; D016254:Mutagenesis, Insertional; D018515:Plant Leaves / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000378:metabolism*; D013430:Sulfate Adenylyltransferase / Q000378:metabolism; D000076988:Sulfate Transporters; D013431:Sulfates / Q000378:metabolism*
C108684:AST68 protein, Arabidopsis; D027321:Anion Transport Proteins; D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D035683:MicroRNAs; D018749:RNA, Plant; D000076988:Sulfate Transporters; D013431:Sulfates; C036483:T-DNA; D013430:Sulfate Adenylyltransferase