Molecular interaction between PHO2 and GIGANTEA reveals a new crosstalk between flowering time and phosphate homeostasis in Oryza sativa.
Plants are often confronted to nutrient limiting conditions, such as inorganic phosphate (Pi) deficiency, resulting in a reduction in growth and yield. PHO2, encoding a ubiquitin-conjugating E2 enzyme, is a central component of the Pi-starvation response signalling pathway. A yeast-two-hybrid screen using Oryza sativa (rice) PHO2 as bait, revealed an interaction between OsPHO2 and OsGIGANTEA, a key regulator of flowering time, which was confirmed using bimolecular fluorescence complementation (BiFC). Characterization of rice Osgi and Ospho2 mutants revealed that they displayed several similar phenotypic features supporting a physiological role for this interaction. Reduced growth, leaf tip necrosis, delayed flowering and over-accumulation of Pi in leaves compared to wild type were shared features of Osgi and Ospho2 plants. Pi analysis of individual leaves demonstrated that Osgi, similar to Ospho2 mutants, were impaired in Pi remobilization from old to young leaves, albeit to a lesser extent. Transcriptome analyses revealed more than 55% of the genes differentially expressed in Osgi plants overlapped with the set of differentially expressed genes in Ospho2 plants. The interaction between OsPHO2 and OsGI links high-level regulators of Pi homeostasis and development in rice.
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.|College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China.
Shuai
S
Li
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Yinghui
Y
Ying
Australian Research Council Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, 6009, WA, Australia.
David
D
Secco
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Chuang
C
Wang
ARC Centre of Excellence in Plant Energy Biology, Department of Animal, Plant and Soil Science, School of Life Science, La Trobe University, Bundoora, VIC, 3086, Australia.
Reena
R
Narsai
ARC Centre of Excellence in Plant Energy Biology, Department of Animal, Plant and Soil Science, School of Life Science, La Trobe University, Bundoora, VIC, 3086, Australia.
James
J
Whelan
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
Huixia
http://orcid.org/0000-0001-6890-5672
H
Shou
D018533:Biomass; D035264:Flowers / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D006706:Homeostasis; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D010641:Phenotype; D010710:Phosphates / Q000378:metabolism*; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D011485:Protein Binding; D013997:Time Factors; D059467:Transcriptome / Q000235:genetics
D010710:Phosphates; D010940:Plant Proteins
UBC24; flowering regulation; phospate signaling pathway; protein-protein interaction