Sucrose Phosphate Synthase Genes in Plants: Its Role and Practice for Crop Improvement.

Plants convert solar energy and carbon dioxide into organic compounds through photosynthesis. Sucrose is the primary carbonate produced during photosynthesis. Sucrose phosphate synthase (SPS) is the key enzyme controlling sucrose biosynthesis in plants. There are at least three gene families in higher plants, named A, B, and C. However, in monocotyledonous plants from Poaceae, there are at least five gene families, named A, B, C, DIII, and DIV. Each family of genes in different plants shows a divergent expression pattern. So different families of genes participate in diverse biological functions, including sucrose accumulation, plant growth and production, and abiotic stress tolerance. SPS activity in plants is regulated by exogenous factors through gene expression and reversible protein phosphorylation. It is a practicable way to improve crop traits through gene transformation. This work analyzes the cloning, phylogeny, and regulatory mechanism of the gene in plants, reviews its biological function as well as its role in crop improvement, and discusses the challenges and future perspectives. This paper can serve as a reference for further study on plant genes and eventually for crop improvement.