Molecular cloning and expression analysis of three genes encoding starch synthase II in rice.
Three starch synthase (SS) genes, OsSSII-1, OsSSII-2 and OsSSII-3, were identified in rice (Oryza sativa L.) and localized to chromosomes 10, 2 and 6, respectively. The three OsSSII full-length cDNAs were cloned, and the predicted amino acid sequences were found to share 52-73% similarity with other members of the plant SSII family. The SS activity of each OsSSII was confirmed by expression and enzyme activity assay in Escherichia coli. Expression profile analysis revealed that OsSSII-1 was expressed in endosperms, leaves and roots; OsSSII-2 was mainly expressed in leaves, while OsSSII-3 was mainly expressed in endosperms. Similar to the OsSSI proteins, the OsSSII-2 and OsSSII-3 proteins were found in the soluble as well as the starch-granule-bound fractions in rice. The roles of the OsSSII proteins in starch biosynthesis in rice and the evolutionary relationships of the genes encoding monocotyledonous and dicotyledonous class-II SS enzymes are discussed.
Jiang
Huawu
H
State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, 310029 Hangzhou, PR China.
Dian
Weimin
W
Liu
Feiyang
F
Wu
Ping
P
D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology* / Q000235:genetics; D010940:Plant Proteins; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013214:Starch Synthase / Q000235:genetics* / Q000378:metabolism*
D010940:Plant Proteins; D011994:Recombinant Proteins; C111377:starch synthase II; D013214:Starch Synthase