Identification of genes encoding granule-bound starch synthase involved in amylose metabolism in banana fruit

PLoS One. 2014 Feb 4;9(2):e88077. doi: 10.1371/journal.pone.0088077. eCollection 2014.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amylose / genetics
  • Amylose / metabolism*
  • Down-Regulation / genetics
  • Fruit / enzymology*
  • Fruit / genetics*
  • Fruit / metabolism
  • Gene Expression Regulation, Enzymologic / genetics
  • Gene Expression Regulation, Plant / genetics
  • Genes, Plant / genetics
  • Musa / enzymology*
  • Musa / genetics*
  • Musa / metabolism
  • Starch Synthase / genetics*
  • Starch Synthase / metabolism
  • Up-Regulation / genetics

Substances

  • Amylose
  • Starch Synthase

Grants and funding

The work is financially supported by the Ministry of Science and Technology of the People's Republic of China (NO. 2011AA10020605) and the Modern Agro-industry Technology Research System (nycytx-33). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.