title: Functional analysis of the novel mycorrhiza-specific phosphate transporter AsPT1 and PHT1 family from Astragalus sinicus during the arbuscular mycorrhizal symbiosis.
abstract: Arbuscular mycorrhizas contribute significantly to inorganic phosphate (Pi) uptake in plants. Gene networks involved in the regulation and function of the Pht1 family transporters in legume species during AM symbiosis are not fully understood. In order to characterize the six distinct members of Pht1 transporters in mycorrhizal Astragalus sinicus, we combined cellular localization, heterologous functional expression in yeast with expression/subcellular localization studies and reverse genetics approaches in planta. Pht1;1 and Pht1;4 silenced lines were generated to uncover the role of the newly discovered dependence of the AM symbiosis on another phosphate transporter AsPT1 besides AsPT4. These Pht1 transporters are triggered in Pi-starved mycorrhizal roots. AsPT1 and AsPT4 were localized in arbuscule-containing cells of the cortex. The analysis of promoter sequences revealed conserved motifs in both AsPT1 and AsPT4. AsPT1 overexpression showed higher mycorrhization levels than controls for parameters analysed, including abundance of arbuscules. By contrast, knockdown of AsPT1 by RNA interference led to degenerating or dead arbuscule phenotypes identical to that of AsPT4 silencing lines. AsPT4 but not AsPT1 is required for symbiotic Pi uptake. These results suggest that both, AsPT1 and AsPT4, are required for the AM symbiosis, most importantly, AsPT1 may serve as a novel symbiotic transporter for AM development.
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Xianan
authors: X
authors: Xie
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Wu
authors: W
authors: Huang
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Fengchuan
authors: F
authors: Liu
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Nianwu
authors: N
authors: Tang
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Yi
authors: Y
authors: Liu
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Hui
authors: H
authors: Lin
authors: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.|College of Life Science and Technology, Huazhong Agricultural University, Wuhan Hubei, 430070, China.
authors: Bin
authors: B
authors: Zhao
mesh_terms: D000595:Amino Acid Sequence; D027883:Astragalus Plant / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology*; D017124:Conserved Sequence; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D038821:Mycorrhizae / Q000502:physiology*; D028061:Phosphate Transport Proteins / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000382:microbiology; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic; D034622:RNA Interference; D013559:Symbiosis / Q000502:physiology*; D015003:Yeasts / Q000235:genetics
chemical_list: D028061:Phosphate Transport Proteins; D010940:Plant Proteins