OsGIF1 (GRAIN INCOMPLETE FILLING 1) gene is considered as domestication gene and encodes a cell-wall invertase required for carbon partitioning during early grain-filling. In wild rice, GIF1 is responsible for grain weight reduction. Ectopic expression of GIF1 gene from cultivated rice with 35S or rice Waxy promoter resulted in smaller grains, whereas overexpression of GIF1 driven by its native promoter increased grain production (Wang et al., 2008). Loss of function mutant of the cell wall invertase gene OsGIF1 were hypersusceptible to postharvest fungal pathogens, with decreased levels of sugars and a thinner glume cell wall in comparison with the wild-type. The GIF1 overexpressing plants accumulated higher levels of glucose, fructose and sucrose compared with the wild-type plants (Sun et al., 2014).