Biosynthesis and Regulation of Wheat Amylose and Amylopectin from Proteomic and Phosphoproteomic Characterization of Granule-binding Proteins.
Waxy starch has an important influence on the qualities of breads. Generally, grain weight and yield in waxy wheat (Triticum aestivum L.) are significantly lower than in bread wheat. In this study, we performed the first proteomic and phosphoproteomic analyses of starch granule-binding proteins by comparing the waxy wheat cultivar Shannong 119 and the bread wheat cultivar Nongda 5181. These results indicate that reduced amylose content does not affect amylopectin synthesis, but it causes significant reduction of total starch biosynthesis, grain size, weight and grain yield. Two-dimensional differential in-gel electrophoresis identified 40 differentially expressed protein (DEP) spots in waxy and non-waxy wheats, which belonged mainly to starch synthase (SS) I, SS IIa and granule-bound SS I. Most DEPs involved in amylopectin synthesis showed a similar expression pattern during grain development, suggesting relatively independent amylose and amylopectin synthesis pathways. Phosphoproteome analysis of starch granule-binding proteins, using TiO2 microcolumns and LC-MS/MS, showed that the total number of phosphoproteins and their phosphorylation levels in ND5181 were significantly higher than in SN119, but proteins controlling amylopectin synthesis had similar phosphorylation levels. Our results revealed the lack of amylose did not affect the expression and phosphorylation of the starch granule-binding proteins involved in amylopectin biosynthesis.
College of Life Science, Capital Normal University, 100048 Beijing, China.
Guan-Xing
GX
Chen
College of Life Science, Capital Normal University, 100048 Beijing, China.
Jian-Wen
JW
Zhou
College of Life Science, Capital Normal University, 100048 Beijing, China.
Yan-Lin
YL
Liu
College of Life Science, Capital Normal University, 100048 Beijing, China.
Xiao-Bing
XB
Lu
College of Life Science, Capital Normal University, 100048 Beijing, China.
Cai-Xia
CX
Han
Hubei Collaborative Innovation Center for Grain Industry, Yangtze University, 434025 Jingzhou, China.
Wen-Ying
WY
Zhang
Hubei Collaborative Innovation Center for Grain Industry, Yangtze University, 434025 Jingzhou, China.
Yan-Hao
YH
Xu
College of Life Science, Capital Normal University, 100048 Beijing, China.|Hubei Collaborative Innovation Center for Grain Industry, Yangtze University, 434025 Jingzhou, China.
Yue-Ming
YM
Yan
D000595:Amino Acid Sequence; D000687:Amylopectin / Q000096:biosynthesis*; D000688:Amylose / Q000096:biosynthesis*; D002523:Edible Grain / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D053858:Metabolic Networks and Pathways; D008958:Models, Molecular; D010766:Phosphorylation; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D040901:Proteomics; D013045:Species Specificity; D013213:Starch / Q000378:metabolism; D013214:Starch Synthase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014908:Triticum / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
D010940:Plant Proteins; D013213:Starch; D000688:Amylose; D000687:Amylopectin; C434607:granule-bound starch synthase I; C111377:starch synthase II; D013214:Starch Synthase