title: Identification of genes encoding granule-bound starch synthase involved in amylose metabolism in banana fruit.
abstract: Granule-bound starch synthase (GBSS) is responsible for amylose synthesis, but the role of GBSS genes and their encoded proteins remains poorly understood in banana. In this study, amylose content and GBSS activity gradually increased during development of the banana fruit, and decreased during storage of the mature fruit. GBSS protein in banana starch granules was approximately 55.0 kDa. The protein was up-regulated expression during development while it was down-regulated expression during storage. Six genes, designated as MaGBSSI-1, MaGBSSI-2, MaGBSSI-3, MaGBSSI-4, MaGBSSII-1, and MaGBSSII-2, were cloned and characterized from banana fruit. Among the six genes, the expression pattern of MaGBSSI-3 was the most consistent with the changes in amylose content, GBSS enzyme activity, GBSS protein levels, and the quantity or size of starch granules in banana fruit. These results suggest that MaGBSSI-3 might regulate amylose metabolism by affecting the variation of GBSS levels and the quantity or size of starch granules in banana fruit during development or storage.
authors: Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China.
authors: Hongxia
authors: H
authors: Miao
authors: Key Laboratory of Genetic Improvement of Bananas, Hainan Province, Haikou Experimental Station, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China.
authors: Peiguang
authors: P
authors: Sun
authors: Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China ; Department of Agriculture, Hainan University, Haikou, Hainan, China.
authors: Weixin
authors: W
authors: Liu
authors: Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China.
authors: Biyu
authors: B
authors: Xu
authors: Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China ; Key Laboratory of Genetic Improvement of Bananas, Hainan Province, Haikou Experimental Station, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China.
authors: Zhiqiang
authors: Z
authors: Jin
mesh_terms: D000688:Amylose / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation / Q000235:genetics; D005638:Fruit / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D028521:Musa / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D013214:Starch Synthase / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation / Q000235:genetics
chemical_list: D000688:Amylose; D013214:Starch Synthase