Open AccessIdentification of Genes Encoding Granule-Bound Starch Synthase Involved in Amylose Metabolism in Banana Fruit
Author(s) -
Hongxia Miao,
Ping Sun,
Weixin Liu,
Biao Xu,
Zhiqiang Jin
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0088077
Subject(s) - starch synthase , amylose , starch , biochemistry , biology , gene , enzyme , granule (geology) , food science , chemistry , amylopectin , paleontology
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.