P0A707 (IF3_ECOLI) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Translation initiation factor IF-3

Cleaved into the following 2 chains:

1. Translation initiation factor IF-3, N-terminally processed
2. Translation initiation factor IF-3S

Gene names

Name:	infC
Synonyms:	fit
Ordered Locus Names:	b1718, JW5829

Organism

Escherichia coli (strain K12) [Reference proteome] [HAMAP]

Taxonomic identifier

83333 [NCBI]

Taxonomic lineage

cellular organisms › Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacteriales › Enterobacteriaceae › Escherichia › Escherichia coli

Protein attributes

Sequence length	180 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	IF-3 binds to the 30S ribosomal subunit and shifts the equilibrum between 70S ribosomes and their 50S and 30S subunits in favor of the free subunits, thus enhancing the availability of 30S subunits on which protein synthesis initiation begins. HAMAP-Rule MF_00080
Subunit structure	Monomer.
Subcellular location	Cytoplasm HAMAP-Rule MF_00080.
Post-translational modification	Phosphorylated on threonine residue(s). Ref.8
Miscellaneous	A short form called IF-3S/IF-3 beta is found both in vivo and in vitro and is probably produced by degradation of the long form IF-3L/IF-3 alpha. HAMAP-Rule MF_00080
Sequence similarities	Belongs to the IF-3 family.
Caution	Was originally (Ref.10) thought to control the translation of its own gene by binding to its mRNA; it now seems that discrimination against the AUU start codon is a kinetic effect (Ref.12).

Ontologies

Keywords
Biological process	Protein biosynthesis
Cellular component	Cytoplasm
Ligand	RNA-binding
Molecular function	Initiation factor
PTM	Cleavage on pair of basic residues Methylation Phosphoprotein
Technical term	3D-structure Complete proteome Direct protein sequencing Reference proteome
Gene Ontology (GO)
Biological_process	response to cold Inferred from direct assay PubMed 14730025. Source: EcoCyc ribosome disassembly Inferred from mutant phenotype PubMed 18565340. Source: EcoCyc
Cellular_component	cytoplasm Inferred from electronic annotation. Source: UniProtKB-SubCell membrane Inferred from direct assay PubMed 16858726. Source: UniProtKB
Molecular_function	ribosome binding Inferred from direct assay PubMed 11684020. Source: EcoCyc translation initiation factor activity Inferred from direct assay PubMed 4922687. Source: EcoCyc
Complete GO annotation...

Binary interactions

With	Entry	#Exp.	IntAct	Notes
rpsG	P02359	3	EBI-546262,EBI-543074

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Chain

1 – 180

180

Translation initiation factor IF-3 HAMAP-Rule MF_00080

PRO_0000367498

Initiator methionine

1

1

Removed; alternate HAMAP-Rule MF_00080

Chain

2 – 180

179

Translation initiation factor IF-3, N-terminally processed HAMAP-Rule MF_00080

PRO_0000014499

Chain

7 – 180

174

Translation initiation factor IF-3S HAMAP-Rule MF_00080

PRO_0000364089

Sites

Site

107

1

Important for 30S binding

Site

110

1

Important for 30S binding

Amino acid modifications

Modified residue

1

1

N-methylmethionine; in Translation initiation factor IF-3; alternate HAMAP-Rule MF_00080

Experimental info

Mutagenesis

107

1

Y → F or L: Reduced ribosome binding. Ref.9

Mutagenesis

110

1

K → R or L: Reduced ribosome binding. Ref.9

Sequence conflict

22

1

Q → E AA sequence Ref.1

Sequence conflict

34 – 36

3

LGI → IGMV AA sequence Ref.1

Sequence conflict

47

1

E → Q AA sequence Ref.1

Sequence conflict

52

1

D → N AA sequence Ref.1

Sequence conflict

61

1

E → Q AA sequence Ref.1

Sequence conflict

87

1

K → E AA sequence Ref.1

Sequence conflict

90

1

V → K AA sequence Ref.1

Sequence conflict

103

1

D → N AA sequence Ref.1

Sequence conflict

105

1

G → N AA sequence Ref.1

Sequence conflict

161

1

F → S in AAA51467. Ref.3

Sequence conflict

178

1

K → Q AA sequence Ref.1

Sequence conflict

180

1

Missing AA sequence Ref.1

Secondary structure

1

.

.

.

.

.

.

.

.

.

.

.

.

.

.

.

180

Helix Strand Turn

Details...

Beta strand

92 – 98

7

Helix

104 – 107

4

Helix

109 – 119

11

Beta strand

122 – 128

7

Helix

140 – 152

13

Turn

153 – 155

3

Beta strand

156 – 159

4

Beta strand

171 – 176

6

Sequences

	Sequence		Length	Mass (Da)
	P0A707 [UniParc]. Last modified July 21, 1986. Version 1. Checksum: 6120EB6AD42E9ABE	FASTA	180	20,564
	10 20 30 40 50 60 MKGGKRVQTA RPNRINGEIR AQEVRLTGLE GEQLGIVSLR EALEKAEEAG VDLVEISPNA 70 80 90 100 110 120 EPPVCRIMDY GKFLYEKSKS SKEQKKKQKV IQVKEIKFRP GTDEGDYQVK LRSLIRFLEE 130 140 150 160 170 180 GDKAKITLRF RGREMAHQQI GMEVLNRVKD DLQELAVVES FPTKIEGRQM IMVLAPKKKQ

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"The primary structure of the initiation factor IF-3 from Escherichia coli." Brauer D., Wittmann-Liebold B. FEBS Lett. 79:269-275(1977) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE, DIFFERENT PROTEIN FORMS, N-TERMINAL METHYLATION. Strain: K.
[2]	"Sequence of a 1.26-kb DNA fragment containing the structural gene for E.coli initiation factor IF3: presence of an AUU initiator codon." Sacerdot C., Fayat G., Dessen P., Springer M., Plumbridge J.A., Grunberg-Manago M., Blanquet S. EMBO J. 1:311-315(1982) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[3]	Miller H.I. Submitted (NOV-1986) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
[4]	"A 570-kb DNA sequence of the Escherichia coli K-12 genome corresponding to the 28.0-40.1 min region on the linkage map." Aiba H., Baba T., Fujita K., Hayashi K., Inada T., Isono K., Itoh T., Kasai H., Kashimoto K., Kimura S., Kitakawa M., Kitagawa M., Makino K., Miki T., Mizobuchi K., Mori H., Mori T., Motomura K. , Nakade S., Nakamura Y., Nashimoto H., Nishio Y., Oshima T., Saito N., Sampei G., Seki Y., Sivasundaram S., Tagami H., Takeda J., Takemoto K., Takeuchi Y., Wada C., Yamamoto Y., Horiuchi T. DNA Res. 3:363-377(1996) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[5]	"The complete genome sequence of Escherichia coli K-12." Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V., Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F., Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B., Shao Y. Science 277:1453-1474(1997) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / MG1655 / ATCC 47076.
[6]	"Highly accurate genome sequences of Escherichia coli K-12 strains MG1655 and W3110." Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S., Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T. Mol. Syst. Biol. 2:E1-E5(2006) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA]. Strain: K12 / W3110 / ATCC 27325 / DSM 5911.
[7]	"Separation of two forms of IF-3 in Escherichia coli by two-dimensional gel electrophoresis." Suryanarayana T., Subramanian A.R. FEBS Lett. 79:264-268(1977) [PubMed] [Europe PMC] [Abstract] Cited for: DIFFERENT PROTEIN FORMS. Strain: Al9, CP78, K and MRE600.
[8]	"Phosphorylation of Escherichia coli translation initiation factors by the bacteriophage T7 protein kinase." Robertson E.S., Nicholson A.W. Biochemistry 31:4822-4827(1992) [PubMed] [Europe PMC] [Abstract] Cited for: PHOSPHORYLATION.
[9]	"Structure-function analysis of Escherichia coli translation initiation factor IF3: tyrosine 107 and lysine 110 are required for ribosome binding." Debellis D., Liveris D., Goss D., Ringquist S., Schwartz I. Biochemistry 31:11984-11990(1992) [PubMed] [Europe PMC] [Abstract] Cited for: MUTAGENESIS OF TYR-107 AND LYS-110.
[10]	"AUU-to-AUG mutation in the initiator codon of the translation initiation factor IF3 abolishes translational autocontrol of its own gene (infC) in vivo." Butler J.S., Springer M., Grunberg-Manago M. Proc. Natl. Acad. Sci. U.S.A. 84:4022-4025(1987) [PubMed] [Europe PMC] [Abstract] Cited for: MECHANISM OF TRANSLATION REGULATION.
[11]	"Escherichia coli proteome analysis using the gene-protein database." VanBogelen R.A., Abshire K.Z., Moldover B., Olson E.R., Neidhardt F.C. Electrophoresis 18:1243-1251(1997) [PubMed] [Europe PMC] [Abstract] Cited for: IDENTIFICATION BY 2D-GEL.
[12]	"How initiation factors maximize the accuracy of tRNA selection in initiation of bacterial protein synthesis." Antoun A., Pavlov M.Y., Lovmar M., Ehrenberg M. Mol. Cell 23:183-193(2006) [PubMed] [Europe PMC] [Abstract] Cited for: MECHANISM OF TRANSLATION REGULATION.
[13]	"Site-directed mutagenesis and NMR spectroscopic approaches to the elucidation of the structure-function relationships in translation initiation factors IF1 and IF3." Spurio R., Paci M., Pawlik R.T., la Teana A., Digiacco B.V., Pon C.L., Gualerzi C.O. Biochimie 73:1001-1006(1991) [PubMed] [Europe PMC] [Abstract] Cited for: STRUCTURE BY NMR, MUTAGENESIS.
[14]	"1H and 15N resonance assignments and structure of the N-terminal domain of Escherichia coli initiation factor 3." Garcia C., Fortier P.-L., Blanquet S., Lallemand J.-Y., Dardel F. Eur. J. Biochem. 228:395-402(1995) [PubMed] [Europe PMC] [Abstract] Cited for: STRUCTURE BY NMR.
[15]	"Heteronuclear NMR studies of E. coli translation initiation factor IF3. Evidence that the inter-domain region is disordered in solution." Moreau M., de Cock E., Fortier P.-L., Garcia C., Albaret C., Blanquet S., Lallemand J.-Y., Dardel F. J. Mol. Biol. 266:15-22(1997) [PubMed] [Europe PMC] [Abstract] Cited for: STRUCTURE BY NMR.
[16]	"On the global architecture of initiation factor IF3: a comparative study of the linker regions from the Escherichia coli protein and the Bacillus stearothermophilus protein." Hua Y., Raleigh D.P. J. Mol. Biol. 278:871-878(1998) [PubMed] [Europe PMC] [Abstract] Cited for: STRUCTURE BY NMR.
[17]	de Cock E., Blanquet S., Lallemand J.-Y., Dardel F. Submitted (DEC-1998) to the PDB data bank Cited for: STRUCTURE BY NMR OF 90-180.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

V00291 Genomic DNA. Translation: CAA23561.1.
K02844 Genomic DNA. Translation: AAA51467.1.
U00096 Genomic DNA. Translation: AAC74788.1.
AP009048 Genomic DNA. Translation: BAA15485.1.

PIR

FIEC3. S13748.

RefSeq

NP_416233.1. NC_000913.2.
YP_489980.1. NC_007779.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
2IFE	NMR	-	A	84-180	[»]

ProteinModelPortal

P0A707.

SMR

P0A707. Positions 15-86, 90-180.

ModBase

Search...

Protein-protein interaction databases

DIP

DIP-36176N.

IntAct

P0A707. 48 interactions.

MINT

MINT-1221578.

STRING

511145.b1718.

PTM databases

PhosSite

P010443.

Proteomic databases

PaxDb

P0A707.

PRIDE

P0A707.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

EnsemblBacteria

AAC74788; AAC74788; b1718.
BAA15485; BAA15485; BAA15485.

GeneID

12933198.
946225.

KEGG

ecj:Y75_p1693.
eco:b1718.

PATRIC

32118740. VBIEscCol129921_1788.

Organism-specific databases

EchoBASE

EB0501.

EcoGene

EG10506. infC.

Phylogenomic databases

eggNOG

COG0290.

HOGENOM

HOG000035157.

KO

K02520.

OMA

APKAPIN.

ProtClustDB

PRK00028.

Enzyme and pathway databases

BioCyc

EcoCyc:EG10506-MONOMER.
ECOL316407:JW5829-MONOMER.

Gene expression databases

Genevestigator

P0A707.

Family and domain databases

Gene3D

3.10.20.80. 1 hit.

HAMAP

MF_00080. IF-3.

InterPro

IPR019813. Translation_initiation_fac3_CS.
IPR001288. Translation_initiation_fac_3.
IPR019815. Translation_initiation_fac_3_C.
IPR019814. Translation_initiation_fac_3_N.
[Graphical view]

PANTHER

PTHR10938. PTHR10938. 1 hit.

Pfam

PF00707. IF3_C. 1 hit.
PF05198. IF3_N. 1 hit.
[Graphical view]

SUPFAM

SSF54364. IF3. 1 hit.
SSF55200. IF3. 1 hit.

TIGRFAMs

TIGR00168. infC. 1 hit.

PROSITE

PS00938. IF3. 1 hit.
[Graphical view]

ProtoNet

Search...

Other

ChEMBL

CHEMBL1075077.

EvolutionaryTrace

P0A707.

Entry information

Entry name

IF3_ECOLI

Accession

Primary (citable) accession number: P0A707
Secondary accession number(s): P02999, P76905

Entry history

Integrated into UniProtKB/Swiss-Prot:	July 21, 1986
Last sequence update:	July 21, 1986
Last modified:	May 1, 2013
This is version 77 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Prokaryotic Protein Annotation Program