ID   IF3_ECOLI               Reviewed;         180 AA.
AC   P0A707; P02999; P76905;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   21-JUL-1986, sequence version 1.
DT   27-MAR-2024, entry version 147.
DE   RecName: Full=Translation initiation factor IF-3 {ECO:0000255|HAMAP-Rule:MF_00080};
DE   Contains:
DE     RecName: Full=Translation initiation factor IF-3, N-terminally processed {ECO:0000255|HAMAP-Rule:MF_00080};
DE   Contains:
DE     RecName: Full=Translation initiation factor IF-3S {ECO:0000255|HAMAP-Rule:MF_00080};
GN   Name=infC {ECO:0000255|HAMAP-Rule:MF_00080}; Synonyms=fit, srjA;
GN   OrderedLocusNames=b1718, JW5829;
OS   Escherichia coli (strain K12).
OC   Bacteria; Pseudomonadota; Gammaproteobacteria; Enterobacterales;
OC   Enterobacteriaceae; Escherichia.
OX   NCBI_TaxID=83333;
RN   [1]
RP   PROTEIN SEQUENCE, DIFFERENT PROTEIN FORMS, SUBCELLULAR LOCATION, AND
RP   METHYLATION AT MET-1.
RC   STRAIN=K;
RX   PubMed=330233; DOI=10.1016/0014-5793(77)80801-6;
RA   Brauer D., Wittmann-Liebold B.;
RT   "The primary structure of the initiation factor IF-3 from Escherichia
RT   coli.";
RL   FEBS Lett. 79:269-275(1977).
RN   [2]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RX   PubMed=6325158; DOI=10.1002/j.1460-2075.1982.tb01166.x;
RA   Sacerdot C., Fayat G., Dessen P., Springer M., Plumbridge J.A.,
RA   Grunberg-Manago M., Blanquet S.;
RT   "Sequence of a 1.26-kb DNA fragment containing the structural gene for
RT   E.coli initiation factor IF3: presence of an AUU initiator codon.";
RL   EMBO J. 1:311-315(1982).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [GENOMIC DNA].
RA   Miller H.I.;
RL   Submitted (NOV-1986) to the EMBL/GenBank/DDBJ databases.
RN   [4]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911;
RX   PubMed=9097039; DOI=10.1093/dnares/3.6.363;
RA   Aiba H., Baba T., Fujita K., Hayashi K., Inada T., Isono K., Itoh T.,
RA   Kasai H., Kashimoto K., Kimura S., Kitakawa M., Kitagawa M., Makino K.,
RA   Miki T., Mizobuchi K., Mori H., Mori T., Motomura K., Nakade S.,
RA   Nakamura Y., Nashimoto H., Nishio Y., Oshima T., Saito N., Sampei G.,
RA   Seki Y., Sivasundaram S., Tagami H., Takeda J., Takemoto K., Takeuchi Y.,
RA   Wada C., Yamamoto Y., Horiuchi T.;
RT   "A 570-kb DNA sequence of the Escherichia coli K-12 genome corresponding to
RT   the 28.0-40.1 min region on the linkage map.";
RL   DNA Res. 3:363-377(1996).
RN   [5]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=K12 / MG1655 / ATCC 47076;
RX   PubMed=9278503; DOI=10.1126/science.277.5331.1453;
RA   Blattner F.R., Plunkett G. III, Bloch C.A., Perna N.T., Burland V.,
RA   Riley M., Collado-Vides J., Glasner J.D., Rode C.K., Mayhew G.F.,
RA   Gregor J., Davis N.W., Kirkpatrick H.A., Goeden M.A., Rose D.J., Mau B.,
RA   Shao Y.;
RT   "The complete genome sequence of Escherichia coli K-12.";
RL   Science 277:1453-1462(1997).
RN   [6]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=K12 / W3110 / ATCC 27325 / DSM 5911;
RX   PubMed=16738553; DOI=10.1038/msb4100049;
RA   Hayashi K., Morooka N., Yamamoto Y., Fujita K., Isono K., Choi S.,
RA   Ohtsubo E., Baba T., Wanner B.L., Mori H., Horiuchi T.;
RT   "Highly accurate genome sequences of Escherichia coli K-12 strains MG1655
RT   and W3110.";
RL   Mol. Syst. Biol. 2:E1-E5(2006).
RN   [7]
RP   DIFFERENT PROTEIN FORMS.
RC   STRAIN=Al9, CP78, K, and MRE600;
RX   PubMed=330232; DOI=10.1016/0014-5793(77)80800-4;
RA   Suryanarayana T., Subramanian A.R.;
RT   "Separation of two forms of IF-3 in Escherichia coli by two-dimensional gel
RT   electrophoresis.";
RL   FEBS Lett. 79:264-268(1977).
RN   [8]
RP   PHOSPHORYLATION.
RX   PubMed=1534259; DOI=10.1021/bi00135a012;
RA   Robertson E.S., Nicholson A.W.;
RT   "Phosphorylation of Escherichia coli translation initiation factors by the
RT   bacteriophage T7 protein kinase.";
RL   Biochemistry 31:4822-4827(1992).
RN   [9]
RP   MUTAGENESIS OF TYR-107 AND LYS-110.
RX   PubMed=1457399; DOI=10.1021/bi00163a005;
RA   Debellis D., Liveris D., Goss D., Ringquist S., Schwartz I.;
RT   "Structure-function analysis of Escherichia coli translation initiation
RT   factor IF3: tyrosine 107 and lysine 110 are required for ribosome
RT   binding.";
RL   Biochemistry 31:11984-11990(1992).
RN   [10]
RP   MECHANISM OF TRANSLATION REGULATION.
RX   PubMed=2954162; DOI=10.1073/pnas.84.12.4022;
RA   Butler J.S., Springer M., Grunberg-Manago M.;
RT   "AUU-to-AUG mutation in the initiator codon of the translation initiation
RT   factor IF3 abolishes translational autocontrol of its own gene (infC) in
RT   vivo.";
RL   Proc. Natl. Acad. Sci. U.S.A. 84:4022-4025(1987).
RN   [11]
RP   IDENTIFICATION BY 2D-GEL.
RX   PubMed=9298644; DOI=10.1002/elps.1150180805;
RA   VanBogelen R.A., Abshire K.Z., Moldover B., Olson E.R., Neidhardt F.C.;
RT   "Escherichia coli proteome analysis using the gene-protein database.";
RL   Electrophoresis 18:1243-1251(1997).
RN   [12]
RP   MECHANISM OF TRANSLATION REGULATION.
RX   PubMed=16857585; DOI=10.1016/j.molcel.2006.05.030;
RA   Antoun A., Pavlov M.Y., Lovmar M., Ehrenberg M.;
RT   "How initiation factors maximize the accuracy of tRNA selection in
RT   initiation of bacterial protein synthesis.";
RL   Mol. Cell 23:183-193(2006).
RN   [13]
RP   FUNCTION, AND SUBUNIT.
RX   PubMed=22562136; DOI=10.1038/nsmb.2285;
RA   Milon P., Maracci C., Filonava L., Gualerzi C.O., Rodnina M.V.;
RT   "Real-time assembly landscape of bacterial 30S translation initiation
RT   complex.";
RL   Nat. Struct. Mol. Biol. 19:609-615(2012).
RN   [14]
RP   REVIEW.
RX   PubMed=22515367; DOI=10.3109/10409238.2012.678284;
RA   Milon P., Rodnina M.V.;
RT   "Kinetic control of translation initiation in bacteria.";
RL   Crit. Rev. Biochem. Mol. Biol. 47:334-348(2012).
RN   [15]
RP   STRUCTURE BY NMR, AND MUTAGENESIS.
RX   PubMed=1742345; DOI=10.1016/0300-9084(91)90141-m;
RA   Spurio R., Paci M., Pawlik R.T., la Teana A., Digiacco B.V., Pon C.L.,
RA   Gualerzi C.O.;
RT   "Site-directed mutagenesis and NMR spectroscopic approaches to the
RT   elucidation of the structure-function relationships in translation
RT   initiation factors IF1 and IF3.";
RL   Biochimie 73:1001-1006(1991).
RN   [16]
RP   STRUCTURE BY NMR.
RX   PubMed=7705354; DOI=10.1111/j.1432-1033.1995.tb20276.x;
RA   Garcia C., Fortier P.-L., Blanquet S., Lallemand J.-Y., Dardel F.;
RT   "1H and 15N resonance assignments and structure of the N-terminal domain of
RT   Escherichia coli initiation factor 3.";
RL   Eur. J. Biochem. 228:395-402(1995).
RN   [17]
RP   STRUCTURE BY NMR.
RX   PubMed=9054966; DOI=10.1006/jmbi.1996.0756;
RA   Moreau M., de Cock E., Fortier P.-L., Garcia C., Albaret C., Blanquet S.,
RA   Lallemand J.-Y., Dardel F.;
RT   "Heteronuclear NMR studies of E. coli translation initiation factor IF3.
RT   Evidence that the inter-domain region is disordered in solution.";
RL   J. Mol. Biol. 266:15-22(1997).
RN   [18]
RP   STRUCTURE BY NMR.
RX   PubMed=9614948; DOI=10.1006/jmbi.1998.1736;
RA   Hua Y., Raleigh D.P.;
RT   "On the global architecture of initiation factor IF3: a comparative study
RT   of the linker regions from the Escherichia coli protein and the Bacillus
RT   stearothermophilus protein.";
RL   J. Mol. Biol. 278:871-878(1998).
RN   [19]
RP   STRUCTURE BY NMR OF 90-180.
RA   de Cock E., Blanquet S., Lallemand J.-Y., Dardel F.;
RL   Submitted (DEC-1998) to the PDB data bank.
RN   [20]
RP   MODEL BY ELECTRON MICROSCOPY (18.3 ANGSTROMS), AND SUBUNIT.
RX   PubMed=21750663; DOI=10.1371/journal.pbio.1001095;
RA   Julian P., Milon P., Agirrezabala X., Lasso G., Gil D., Rodnina M.V.,
RA   Valle M.;
RT   "The cryo-EM structure of a complete 30S translation initiation complex
RT   from Escherichia coli.";
RL   PLoS Biol. 9:E1001095-E1001095(2011).
CC   -!- FUNCTION: One of the essential components for the initiation of protein
CC       synthesis.IF-3 binds to the 30S ribosomal subunit and shifts the
CC       equilibrium between 70S ribosomes and their 50S and 30S subunits in
CC       favor of the free subunits, thus enhancing the availability of 30S
CC       subunits on which protein synthesis initiation begins.
CC       {ECO:0000269|PubMed:22562136}.
CC   -!- SUBUNIT: Monomer. Component of the 30S ribosomal translation pre-
CC       initiation complex which assembles on the 30S ribosome in the order IF-
CC       2 and IF-3, IF-1 and N-formylmethionyl-tRNA(fMet); mRNA recruitment can
CC       occur at any time during PIC assembly. {ECO:0000269|PubMed:22562136}.
CC   -!- INTERACTION:
CC       P0A707; P02359: rpsG; NbExp=4; IntAct=EBI-546262, EBI-543074;
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:330233}.
CC   -!- PTM: Phosphorylated on threonine residue(s).
CC       {ECO:0000269|PubMed:1534259}.
CC   -!- PTM: The form lacking the initiator methionine is less abundant than
CC       the N-methylmethionine form. {ECO:0000269|PubMed:330233}.
CC   -!- MISCELLANEOUS: A short form called IF-3S/IF-3 beta is found both in
CC       vivo and in vitro and is probably produced by degradation of the long
CC       form IF-3L/IF-3 alpha. The major form is the N-methylmethionine long
CC       form. {ECO:0000269|PubMed:330233}.
CC   -!- MISCELLANEOUS: Uses the non-canonical initiation codon AUU, which
CC       limits its expression (PubMed:16857585). {ECO:0000305|PubMed:16857585}.
CC   -!- SIMILARITY: Belongs to the IF-3 family. {ECO:0000255|HAMAP-
CC       Rule:MF_00080}.
CC   -!- CAUTION: Was originally (PubMed:2954162) thought to control the
CC       translation of its own gene by binding to its mRNA; it now seems that
CC       discrimination against the AUU start codon is a kinetic effect
CC       (PubMed:16857585). {ECO:0000305|PubMed:16857585,
CC       ECO:0000305|PubMed:2954162}.
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DR   EMBL; V00291; CAA23561.1; -; Genomic_DNA.
DR   EMBL; K02844; AAA51467.1; -; Genomic_DNA.
DR   EMBL; U00096; AAC74788.1; -; Genomic_DNA.
DR   EMBL; AP009048; BAA15485.1; -; Genomic_DNA.
DR   PIR; S13748; FIEC3.
DR   RefSeq; NP_416233.1; NC_000913.3.
DR   RefSeq; WP_001700733.1; NZ_STEB01000009.1.
DR   PDB; 2IFE; NMR; -; A=81-180.
DR   PDB; 5ME0; EM; 13.50 A; Z=38-180.
DR   PDB; 5ME1; EM; 13.50 A; Z=37-180.
DR   PDBsum; 2IFE; -.
DR   PDBsum; 5ME0; -.
DR   PDBsum; 5ME1; -.
DR   AlphaFoldDB; P0A707; -.
DR   BMRB; P0A707; -.
DR   EMDB; EMD-3494; -.
DR   EMDB; EMD-3495; -.
DR   SMR; P0A707; -.
DR   BioGRID; 4262192; 98.
DR   ComplexPortal; CPX-2244; Translation initiation factor complex.
DR   DIP; DIP-36176N; -.
DR   IntAct; P0A707; 51.
DR   STRING; 511145.b1718; -.
DR   ChEMBL; CHEMBL1075077; -.
DR   iPTMnet; P0A707; -.
DR   jPOST; P0A707; -.
DR   PaxDb; 511145-b1718; -.
DR   EnsemblBacteria; AAC74788; AAC74788; b1718.
DR   GeneID; 83576799; -.
DR   GeneID; 946225; -.
DR   KEGG; ecj:JW5829; -.
DR   KEGG; eco:b1718; -.
DR   PATRIC; fig|511145.12.peg.1788; -.
DR   EchoBASE; EB0501; -.
DR   eggNOG; COG0290; Bacteria.
DR   HOGENOM; CLU_054919_3_2_6; -.
DR   InParanoid; P0A707; -.
DR   OMA; KCTVIFR; -.
DR   OrthoDB; 9806014at2; -.
DR   PhylomeDB; P0A707; -.
DR   BioCyc; EcoCyc:EG10506-MONOMER; -.
DR   EvolutionaryTrace; P0A707; -.
DR   PRO; PR:P0A707; -.
DR   Proteomes; UP000000318; Chromosome.
DR   Proteomes; UP000000625; Chromosome.
DR   GO; GO:0005829; C:cytosol; IDA:EcoCyc.
DR   GO; GO:0016020; C:membrane; HDA:UniProtKB.
DR   GO; GO:0043022; F:ribosome binding; IDA:EcoCyc.
DR   GO; GO:0003723; F:RNA binding; IEA:UniProtKB-KW.
DR   GO; GO:0003743; F:translation initiation factor activity; IDA:EcoCyc.
DR   GO; GO:0009409; P:response to cold; IDA:EcoCyc.
DR   GO; GO:0032790; P:ribosome disassembly; IMP:EcoCyc.
DR   DisProt; DP00197; -.
DR   Gene3D; 3.30.110.10; Translation initiation factor 3 (IF-3), C-terminal domain; 1.
DR   Gene3D; 3.10.20.80; Translation initiation factor 3 (IF-3), N-terminal domain; 1.
DR   HAMAP; MF_00080; IF_3; 1.
DR   InterPro; IPR036788; T_IF-3_C_sf.
DR   InterPro; IPR036787; T_IF-3_N_sf.
DR   InterPro; IPR019813; Translation_initiation_fac3_CS.
DR   InterPro; IPR001288; Translation_initiation_fac_3.
DR   InterPro; IPR019815; Translation_initiation_fac_3_C.
DR   InterPro; IPR019814; Translation_initiation_fac_3_N.
DR   NCBIfam; TIGR00168; infC; 1.
DR   PANTHER; PTHR10938; TRANSLATION INITIATION FACTOR IF-3; 1.
DR   PANTHER; PTHR10938:SF0; TRANSLATION INITIATION FACTOR IF-3, MITOCHONDRIAL; 1.
DR   Pfam; PF00707; IF3_C; 1.
DR   Pfam; PF05198; IF3_N; 1.
DR   SUPFAM; SSF55200; Translation initiation factor IF3, C-terminal domain; 1.
DR   SUPFAM; SSF54364; Translation initiation factor IF3, N-terminal domain; 1.
DR   PROSITE; PS00938; IF3; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Cleavage on pair of basic residues; Cytoplasm;
KW   Direct protein sequencing; Initiation factor; Methylation; Phosphoprotein;
KW   Protein biosynthesis; Reference proteome; RNA-binding.
FT   CHAIN           1..180
FT                   /note="Translation initiation factor IF-3"
FT                   /evidence="ECO:0000305|PubMed:330233"
FT                   /id="PRO_0000367498"
FT   INIT_MET        1
FT                   /note="Removed; alternate"
FT                   /evidence="ECO:0000269|PubMed:330233"
FT   CHAIN           2..180
FT                   /note="Translation initiation factor IF-3, N-terminally
FT                   processed"
FT                   /evidence="ECO:0000305|PubMed:330233"
FT                   /id="PRO_0000014499"
FT   CHAIN           7..180
FT                   /note="Translation initiation factor IF-3S"
FT                   /evidence="ECO:0000305|PubMed:330233"
FT                   /id="PRO_0000364089"
FT   SITE            107
FT                   /note="Important for 30S binding"
FT                   /evidence="ECO:0000305|PubMed:1457399"
FT   SITE            110
FT                   /note="Important for 30S binding"
FT                   /evidence="ECO:0000305|PubMed:1457399"
FT   MOD_RES         1
FT                   /note="N-methylmethionine; in Translation initiation factor
FT                   IF-3; alternate"
FT                   /evidence="ECO:0000269|PubMed:330233"
FT   MUTAGEN         107
FT                   /note="Y->F,L: Reduced ribosome binding."
FT                   /evidence="ECO:0000269|PubMed:1457399"
FT   MUTAGEN         110
FT                   /note="K->R,L: Reduced ribosome binding."
FT                   /evidence="ECO:0000269|PubMed:1457399"
FT   CONFLICT        22
FT                   /note="Q -> E (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        34..36
FT                   /note="LGI -> IGMV (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        47
FT                   /note="E -> Q (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        52
FT                   /note="D -> N (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        61
FT                   /note="E -> Q (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        87
FT                   /note="K -> E (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        90
FT                   /note="V -> K (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        103
FT                   /note="D -> N (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        105
FT                   /note="G -> N (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        161
FT                   /note="F -> S (in Ref. 3; AAA51467)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        178
FT                   /note="K -> Q (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        180
FT                   /note="Missing (in Ref. 1; AA sequence)"
FT                   /evidence="ECO:0000305"
FT   STRAND          92..98
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   HELIX           104..107
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   HELIX           109..119
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   STRAND          122..128
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   HELIX           140..152
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   TURN            153..155
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   STRAND          156..159
FT                   /evidence="ECO:0007829|PDB:2IFE"
FT   STRAND          171..176
FT                   /evidence="ECO:0007829|PDB:2IFE"
SQ   SEQUENCE   180 AA;  20564 MW;  6120EB6AD42E9ABE CRC64;
     MKGGKRVQTA RPNRINGEIR AQEVRLTGLE GEQLGIVSLR EALEKAEEAG VDLVEISPNA
     EPPVCRIMDY GKFLYEKSKS SKEQKKKQKV IQVKEIKFRP GTDEGDYQVK LRSLIRFLEE
     GDKAKITLRF RGREMAHQQI GMEVLNRVKD DLQELAVVES FPTKIEGRQM IMVLAPKKKQ
//