Functional characterization of the rice SPX-MFS family reveals a key role of OsSPX-MFS1 in controlling phosphate homeostasis in leaves.
• Proteins possessing the SPX domain are found in several proteins involved in inorganic phosphate (Pi) transport and signalling in yeast and plants. Although the functions of several SPX-domain protein subfamilies have recently been uncovered, the role of the SPX-MFS subfamily is still unclear. • Using quantitative RT-PCR analysis, we studied the regulation of SPX-MFS gene expression by the central regulator, OsPHR2 and Pi starvation. The function of OsSPX-MFS1 in Pi homeostasis was analysed using an OsSPX-MFS1 mutant (mfs1) and osa-miR827 overexpression line (miR827-Oe). Finally, heterologous complementation of a yeast mutant impaired in Pi transporter was used to assess the capacity of OsSPX-MFS1 to transport Pi. • Transcript analyses revealed that members of the SPX-MFS family were mainly expressed in the shoots, with OsSPX-MFS1 and OsSPX-MFS3 being suppressed by Pi deficiency, while OsSPX-MFS2 was induced. Mutation in OsSPX-MFS1 (mfs1) and overexpression of the upstream miR827 (miR827-Oe) plants impaired Pi homeostasis in the leaves. In addition, studies in yeast revealed that OsSPX-MFS1 may be involved in Pi transport. • The results suggest that OsSPX-MFS1 is a key player in maintaining Pi homeostasis in the leaves, potentially acting as a Pi transporter.
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.|Joint Research Laboratory in Genomics and Nutriomics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Chuang
C
Wang
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Wei
W
Huang
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Yinghui
Y
Ying
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Shuai
S
Li
Joint Research Laboratory in Genomics and Nutriomics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.|Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley 6009, WA, Australia.
David
D
Secco
Australian Research Council Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, PMB1, Glen Osmond, SA 5064, Australia.
Steve
S
Tyerman
Joint Research Laboratory in Genomics and Nutriomics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.|Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley 6009, WA, Australia.
James
J
Whelan
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.|Joint Research Laboratory in Genomics and Nutriomics, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Huixia
H
Shou
D000595:Amino Acid Sequence; D001692:Biological Transport / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics*; D017930:Genes, Reporter; D005816:Genetic Complementation Test; D005966:Glucuronidase / Q000378:metabolism; D006706:Homeostasis / Q000187:drug effects / Q000235:genetics; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D010710:Phosphates / Q000172:deficiency / Q000378:metabolism* / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000235:genetics; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics
D035683:MicroRNAs; D010710:Phosphates; D010940:Plant Proteins; D005966:Glucuronidase