P0C586 (SSY23_ORYSI) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Soluble starch synthase 2-3, chloroplastic/amyloplastic
EC=2.4.1.21

Alternative name(s):
Soluble starch synthase II-3
Starch synthase IIa

Gene names

Name:	SSII-3
Synonyms:	ALK

Organism

Oryza sativa subsp. indica (Rice)

Taxonomic identifier

39946 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Viridiplantae › Streptophyta › Streptophytina › Embryophyta › Tracheophyta › Euphyllophyta › Spermatophyta › Magnoliophyta › Liliopsida › commelinids › Poales › Poaceae › BEP clade › Ehrhartoideae › Oryzeae › Oryza › Oryza sativa

Protein attributes

Sequence length	810 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Plays an important role during endosperm starch synthesis. Determines the type of amylopectin structure of starch grain. Synthesizes long B1 amylopectin chains by elongating short A and B1 chains, independently of the other soluble starch synthases. Barely active in japonica subspecies. Ref.2 Ref.3
Catalytic activity	ADP-glucose + (1,4-alpha-D-glucosyl)(n) = ADP + (1,4-alpha-D-glucosyl)(n+1).
Pathway	Glycan biosynthesis; starch biosynthesis.
Subcellular location	Plastid › amyloplast. Plastid › chloroplast. Note: Amyloplast or chloroplast, granule-bound and soluble. Ref.3 Ref.4
Tissue specificity	Expressed most exclusively in endosperm. Ref.3 Ref.4
Developmental stage	Expressed in developing caryopsis at 5 to 15 days after flowering. Expressed exclusively in the endosperm at 5 to 10 days after flowering. Ref.3
Miscellaneous	Increased activity due to variations in subspecies indica is associated with the synthesis of the L-type amylopectin, which contains much lower proportion of short amylopectin chains than the S-type amylopectin found in most japonica varieties. The difference in amylopectin chain composition explains why starch from japonica subspecies has a lower gelatinisation temperature than starch from indica subspecies.
Sequence similarities	Belongs to the glycosyltransferase 1 family. Bacterial/plant glycogen synthase subfamily.
Sequence caution	The sequence AAQ99280.1 differs from that shown. Reason: Erroneous gene model prediction.

Ontologies

Keywords
Biological process	Starch biosynthesis
Cellular component	Amyloplast Chloroplast Plastid
Domain	Transit peptide
Molecular function	Glycosyltransferase Transferase
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological_process	starch biosynthetic process Inferred from electronic annotation. Source: UniProtKB-UniPathway
Cellular_component	amyloplast Inferred from electronic annotation. Source: UniProtKB-SubCell chloroplast Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	starch synthase activity Inferred from electronic annotation. Source: EC
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Transit peptide	1 – 16	16	Chloroplast Potential
	Chain	17 – 810	794	Soluble starch synthase 2-3, chloroplastic/amyloplastic		PRO_0000295651
Regions
	Compositional bias	53 – 60	8	Poly-Pro
	Compositional bias	178 – 235	58	Pro-rich
	Compositional bias	278 – 309	32	Asp-rich
Sites
	Binding site	333	1	ADP-glucose By similarity
Experimental info
	Mutagenesis	88	1	E → D: Reduced activity; when associated with F-781. Loss of activity; when associated with M-737. Loss of activity; when associated with S-604 and F-781. Ref.2
	Mutagenesis	604	1	G → S: Loss of activity; when associated with M-737 and/or F-781. Ref.2
	Mutagenesis	737	1	V → M: Loss of activity. Loss of activity; when associated with D-88 and/or S-604 and/or F-781. Ref.2
	Mutagenesis	781	1	L → F: Reduced activity. Reduced activity; when associated with D-88. Loss of activity; when associated with S-604 and/or M-737. Ref.2

Sequences

	Sequence		Length	Mass (Da)
	P0C586 [UniParc]. Last modified July 24, 2007. Version 1. Checksum: A08DE310DC90B319	FASTA	810	88,327
	10 20 30 40 50 60 MSSAVVASST TFLVALASSA SRGGPRRGRV VGVAAPPALL YDGRAGRLAL RAPPPPRPRP 70 80 90 100 110 120 RRRDAGVVRR ADDGENEAAV ERAGEDDEEE EEFSSGAWQP PRSRRGGVGK VLKRRGTVPP 130 140 150 160 170 180 VGRYGSGGDA ARVRGAAAPA PAPTQDAASS KNGALLSGRD DDTPASRNGS VVTGADKPAA 190 200 210 220 230 240 ATPPVTITKL PAPDSPVILP SVDKPQPEFV IPDATAPAPP PPGSNPRSSA PLPKPDNSEF 250 260 270 280 290 300 AEDKSAKVVE SAPKPKATRS SPIPAVEEET WDFKKYFDLN EPDAAEDGDD DDDWADSDAS 310 320 330 340 350 360 DSEIDQDDDS GPLAGENVMN VIVVAAECSP WCKTGGLGDV AGALPKALAR RGHRVMVVVP 370 380 390 400 410 420 RYGDYAEAQD VGIRKYYKAA GQDLEVKYFH AFIDGVDFVF IDAPLFRHRQ DDIYGGNRQE 430 440 450 460 470 480 IMKRMILFCK AAVEVPWHVP CGGVPYGDGN LVFLANDWHT ALLPVYLKAY YRDNGMMQYT 490 500 510 520 530 540 RSVLVIHNIA YQGRGPVDEF PYMELPEHYL DHFKLYDPVG GEHANIFGAG LKMADRVVTV 550 560 570 580 590 600 SPGYLWELKT TEGGWGLHDI IRENDWKMNG IVNGIDYREW NPEVDVHLQS DGYANYTVAS 610 620 630 640 650 660 LDSGKPRCKA ALQRELGLEV RDDVPLIGFI GRLDGQKGVD IIGDAMPWIA GQDVQLVLLG 670 680 690 700 710 720 SGRRDLEVML QRFEAQHNSK VRGWVGFSVK MAHRITAGAD VLVMPSRFEP CGLNQLYAMA 730 740 750 760 770 780 YGTVPVVHAV GGLRDTVSAF DPFEDTGLGW TFDRAEPHKL IEALGHCLET YRKYKESWRG 790 800 810 LQVRGMSQDL SWDHAAELYE EVLVKAKYQW

References

[1]	"Map-based cloning of the ALK gene, which controls the gelatinization temperature of rice." Gao Z., Zeng D., Cui X., Zhou Y., Yan M., Huang D., Li J., Qian Q. Sci. China, Ser. C, Life Sci. 46:661-668(2003) Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: cv. Shuangke Zao.
[2]	"Essential amino acids of starch synthase IIa differentiate amylopectin structure and starch quality between japonica and indica rice varieties." Nakamura Y., Francisco P.B. Jr., Hosaka Y., Sato A., Sawada T., Kubo A., Fujita N. Plant Mol. Biol. 58:213-227(2005) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, MUTAGENESIS OF GLU-88; GLY-604; VAL-737 AND LEU-781. Strain: cv. IR36 and cv. Kasalath.
[3]	"Molecular cloning and expression analysis of three genes encoding starch synthase II in rice." Jiang H.W., Dian W.M., Liu F., Wu P. Planta 218:1062-1070(2004) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 71-78, FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY, DEVELOPMENTAL STAGE.
[4]	"A comprehensive expression analysis of the starch synthase gene family in rice (Oryza sativa L.)." Hirose T., Terao T. Planta 220:9-16(2004) [PubMed] [Europe PMC] [Abstract] Cited for: SUBCELLULAR LOCATION, TISSUE SPECIFICITY, NOMENCLATURE.

Cross-references

Sequence databases
EMBL GenBank DDBJ	AY423717 Genomic DNA. Translation: AAQ99280.1. Sequence problems. AB115917 mRNA. Translation: BAD90593.1. AB115918 mRNA. Translation: BAD90594.1.
UniGene	Os.5738.
3D structure databases
ProteinModelPortal	P0C586.
ModBase	Search...
Protein family/group databases
CAZy	GT5. Glycosyltransferase Family 5.
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Organism-specific databases
Gramene	P0C586.
Phylogenomic databases
eggNOG	COG0297.
HOGENOM	HOG000294940.
Enzyme and pathway databases
UniPathway	UPA00152.
Gene expression databases
ArrayExpress	P0C586.
Family and domain databases
InterPro	IPR001296. Glyco_trans_1. IPR011835. Glycogen/starch_synth. IPR013534. Starch_synth_cat_dom. [Graphical view]
Pfam	PF08323. Glyco_transf_5. 1 hit. PF00534. Glycos_transf_1. 1 hit. [Graphical view]
TIGRFAMs	TIGR02095. glgA. 1 hit.
ProtoNet	Search...

Entry information

Entry name

SSY23_ORYSI

Accession

Primary (citable) accession number: P0C586
Secondary accession number(s): Q5DWW9 , Q5DWX1, Q67X47, Q6TDS3, Q944W5

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 24, 2007
Last sequence update:	July 24, 2007
Last modified:	April 3, 2013
This is version 32 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program