P51133 (UCRI3_TOBAC) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Cytochrome b-c1 complex subunit Rieske-3, mitochondrial EC=1.10.2.2 Alternative name(s): Complex III subunit 5-3 Rieske iron-sulfur protein 3 Short name=RISP3 Ubiquinol-cytochrome c reductase iron-sulfur subunit 3
Organism	Nicotiana tabacum (Common tobacco)
Taxonomic identifier	4097 [NCBI]
Taxonomic lineage	Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › lamiids › Solanales › Solanaceae › Nicotianoideae › Nicotianeae › Nicotiana

Protein attributes

Sequence length	268 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at transcript level

General annotation (Comments)

Function	Component of the ubiquinol-cytochrome c reductase complex (complex III or cytochrome b-c1 complex), which is a respiratory chain that generates an electrochemical potential coupled to ATP synthesis.
Catalytic activity	QH2 + 2 ferricytochrome c = Q + 2 ferrocytochrome c + 2 H+.
Cofactor	Binds 1 2Fe-2S cluster per subunit By similarity.
Subunit structure	The bc1 complex contains 10 subunits; 3 respiratory subunits, 2 core proteins and 5 low-molecular weight proteins.
Subcellular location	Mitochondrion inner membrane.
Tissue specificity	High levels are seen in the flowers while a low level expression is seen in the roots, leaves and stems.
Miscellaneous	The Rieske protein is a high potential 2Fe-2S protein.
Sequence similarities	Contains 1 Rieske domain.

Ontologies

Keywords
Biological process	Electron transport Respiratory chain Transport
Cellular component	Membrane Mitochondrion Mitochondrion inner membrane
Domain	Transit peptide Transmembrane
Ligand	2Fe-2S Iron Iron-sulfur Metal-binding
Molecular function	Oxidoreductase
PTM	Disulfide bond
Gene Ontology (GO)
Biological process	electron transport chain Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW mitochondrial inner membrane Inferred from electronic annotation. Source: UniProtKB-SubCell respiratory chain Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	2 iron, 2 sulfur cluster binding Inferred from electronic annotation. Source: UniProtKB-KW metal ion binding Inferred from electronic annotation. Source: UniProtKB-KW ubiquinol-cytochrome-c reductase 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 – 56	56	Mitochondrion Potential
	Chain	57 – 268	212	Cytochrome b-c1 complex subunit Rieske-3, mitochondrial		PRO_0000030678
Regions
	Domain	178 – 266	89	Rieske
Sites
	Metal binding	211	1	Iron-sulfur (2Fe-2S) By similarity
	Metal binding	213	1	Iron-sulfur (2Fe-2S); via pros nitrogen By similarity
	Metal binding	230	1	Iron-sulfur (2Fe-2S) By similarity
	Metal binding	233	1	Iron-sulfur (2Fe-2S); via pros nitrogen By similarity
Amino acid modifications
	Disulfide bond	216 ↔ 232		By similarity

Sequences

	Sequence		Length	Mass (Da)
	P51133 [UniParc]. Last modified October 1, 1996. Version 1. Checksum: 56E4BA99AAEC6FDF	FASTA	268	29,246
	10 20 30 40 50 60 MLRIAGRKLS SSAATRSSSA FFTRNPFTFT DDSSSPARSP SPASLASQFL DQFRGFSSNS 70 80 90 100 110 120 VSPAHQTGLV SDLPATVAAI KNPSSKIVYD DSNHERYPPG DPSKRAFAYF VLTGGRFVYA 130 140 150 160 170 180 SLVRLLILKF VLSMSASKDV LALASLEVDL SSIEPGTTVT VKWRGKPVFI RRRTEEDINL 190 200 210 220 230 240 ANSVDLGSLR DPQQDAERVK NPEWLVVIGV CTHLGCIPLP NAGDFGGWFC PCHGSHYDIS 250 260 GRIRKGPAPY NLEVPTYSFM EENKLLIG

References

[1]	"Flower-enhanced expression of a nuclear-encoded mitochondrial respiratory protein is associated with changes in mitochondrion number." Huang J., Struck F., Matzinger D.F., Levings C.S. III Plant Cell 6:439-448(1994) [PubMed: 8180500] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. SC58. Tissue: Flower.
+	Additional computationally mapped references.

Cross-references

Sequence databases
EMBL GenBank DDBJ	L16811 mRNA. Translation: AAA20832.1.
PIR	T02025.
3D structure databases
ProteinModelPortal	P51133.
SMR	P51133. Positions 101-268.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
InterPro	IPR017941. Rieske_2Fe-2S. IPR014349. Rieske_Fe-S_prot. IPR005805. Rieske_Fe-S_prot_C. IPR006317. Ubiquinol_cyt_c_Rdtase_Fe-S-su. IPR004192. Ubiquinol_cyt_Rdtase_TM. [Graphical view]
Gene3D	G3DSA:2.102.10.10. Rieske_reg. 1 hit. G3DSA:1.20.5.270. Ubiquinol_cyt_Rdtase_TM. 1 hit.
PANTHER	PTHR10134. Rieske. 1 hit.
Pfam	PF00355. Rieske. 1 hit. PF02921. UCR_TM. 1 hit. [Graphical view]
PRINTS	PR00162. RIESKE.
SUPFAM	SSF50022. Rieske_dom. 1 hit. SSF81502. UCR_TM_region. 1 hit.
TIGRFAMs	TIGR01416. Rieske_proteo. 1 hit.
PROSITE	PS51296. RIESKE. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

UCRI3_TOBAC

Accession

Primary (citable) accession number: P51133

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 1, 1996
Last sequence update:	October 1, 1996
Last modified:	May 31, 2011
This is version 72 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Plant Protein Annotation Program