title: Sucrose phosphate synthase and sucrose phosphate phosphatase interact in planta and promote plant growth and biomass accumulation.
abstract: Bioinformatic analysis indicates that sucrose phosphate synthase (SPS) contains a putative C-terminal sucrose phosphate phosphatase (SPP)-like domain that may facilitates the binding of SPP. If an SPS-SPP enzyme complex exists, it may provide sucrose biosynthesis with an additional level of regulation, forming a direct metabolic channel for sucrose-6-phosphate between these two enzymes. Herein, the formation of an enzyme complex between SPS and SPP was examined, and the results from yeast two-hybrid experiments suggest that there is indeed an association between these proteins. In addition, in planta bioluminescence resonance energy transfer (BRET) was observed in Arabidopsis seedlings, providing physical evidence for a protein interaction in live cells and in real time. Finally, bimolecular fluorescence complementation (BiFC) was employed in an attempt to detect SPS-SPP interactions visually. The findings clearly demonstrated that SPS interacts with SPP and that this interaction impacts soluble carbohydrate pools and affects carbon partitioning to starch. Moreover, a fusion construct between the two genes promotes plant growth in both transgenic Arabidopsis and hybrid poplar.
authors: Department of Wood Science, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
authors: Victoria J
authors: VJ
authors: Maloney
authors: Department of Wood Science, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
authors: Ji-Young
authors: JY
authors: Park
authors: Department of Wood Science, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada.
authors: Faride
authors: F
authors: Unda
authors: Department of Wood Science, University of British Columbia, 2424 Main Mall, Vancouver, BC, V6T 1Z4, Canada shawn.mansfield@ubc.ca.
authors: Shawn D
authors: SD
authors: Mansfield
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism; D018533:Biomass; D005964:Glucosyltransferases / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010944:Plants / Q000378:metabolism*; D011485:Protein Binding
chemical_list: D005964:Glucosyltransferases; C022698:sucrose-phosphate synthase; C083874:sucrose-phosphate synthase phosphatase; D010749:Phosphoprotein Phosphatases
keywords: BRET; BiFC; biomass; cellulose; poplar; protein–protein interaction; sucrose phosphate phosphatase; sucrose phosphate synthase; yeast two-hybrid.