ISA — Oryza sativa Japonica

Summary

OsISA (OS08G0520900) on rice chromosome 8 encodes a protein with isoamylase activity (EC 3.2.1.68), 1,4-alpha-glucan branching enzyme activity, cation binding, and O-glucosyl hydrolase activity, belonging to the glycoside hydrolase superfamily. The gene is associated with starch granule initiation, amylopectin and glycogen anabolism and breakdown, amyloplast organization, endosperm development, and embryo development ending in seed dormancy. It localizes to the isoamylase complex, chloroplast isoamylase complex, amyloplast, and cytoplasm. Observed phenotypes include effects on starch and endosperm. The gene is linked to sugary, dull, and floury endosperm traits, grain appearance, amylose content, seed weight, sugar, starch, and protein content, and grain yield. Studies of related genes in other species connect the family to starch metabolism and arabinose metabolism, and to starch biosynthesis and accumulation.

Annotations

Chromosome
8
Related genes
ISA, ISA1
GO terms
taste, NO storage, Digestion, carbohydrate metabolism, Embryo Development Ending In Seed Dormancy, glycogen anabolism, Amyloplast, starch anabolism
Publications
15749471, 23393426, 25663508, PMID:15862090, PMID:7773016, PMID:12834068, PMID:16953433, PMID:20018713
Traits
arabinose metabolism, Modified amylopectin structure with increased short chains, decreased long chains, Reduced Starch, Increased Soluble Glucan Accumulation, Reduced Leaf Starch Content, Defective Amylopectin Biosynthesis, Reduced Starch, Phytoglycogen Production, No Change in Amylose-Amylopectin Ratio, Normal Maltose and Maltotriose Production, Increased water soluble polysaccharides content