ID A0A3Q3NCG0_9TELE Unreviewed; 904 AA.
AC A0A3Q3NCG0;
DT 10-APR-2019, integrated into UniProtKB/TrEMBL.
DT 02-JUN-2021, sequence version 2.
DT 18-JUN-2025, entry version 31.
DE RecName: Full=Eukaryotic translation initiation factor 5B {ECO:0000256|ARBA:ARBA00013824};
DE EC=3.6.5.3 {ECO:0000256|ARBA:ARBA00011986};
DE AltName: Full=Translation initiation factor IF-2 {ECO:0000256|ARBA:ARBA00032478};
OS Mastacembelus armatus (zig-zag eel).
OC Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC Actinopterygii; Neopterygii; Teleostei; Neoteleostei; Acanthomorphata;
OC Anabantaria; Synbranchiformes; Mastacembelidae; Mastacembelus.
OX NCBI_TaxID=205130 {ECO:0000313|Ensembl:ENSMAMP00000033576.2, ECO:0000313|Proteomes:UP000261640};
RN [1] {ECO:0000313|Ensembl:ENSMAMP00000033576.2}
RP IDENTIFICATION.
RG Ensembl;
RL Submitted (MAR-2025) to UniProtKB.
CC -!- FUNCTION: Plays a role in translation initiation. Ribosome-dependent
CC GTPase that promotes the joining of the 60S ribosomal subunit to the
CC pre-initiation complex to form the 80S initiation complex with the
CC initiator methionine-tRNA in the P-site base paired to the start codon.
CC Together with eIF1A (EIF1AX), actively orients the initiator
CC methionine-tRNA in a conformation that allows 60S ribosomal subunit
CC joining to form the 80S initiation complex. Is released after formation
CC of the 80S initiation complex. Its GTPase activity is not essential for
CC ribosomal subunits joining, but GTP hydrolysis is needed for eIF1A
CC (EIF1AX) ejection quickly followed by EIF5B release to form elongation-
CC competent ribosomes. In contrast to its procaryotic homolog, does not
CC promote recruitment of Met-rRNA to the small ribosomal subunit.
CC {ECO:0000256|ARBA:ARBA00053410}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=GTP + H2O = GDP + phosphate + H(+); Xref=Rhea:RHEA:19669,
CC ChEBI:CHEBI:15377, ChEBI:CHEBI:15378, ChEBI:CHEBI:37565,
CC ChEBI:CHEBI:43474, ChEBI:CHEBI:58189; EC=3.6.5.3;
CC Evidence={ECO:0000256|ARBA:ARBA00051990};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:19670;
CC Evidence={ECO:0000256|ARBA:ARBA00051990};
CC -!- COFACTOR:
CC Name=a monovalent cation; Xref=ChEBI:CHEBI:60242;
CC Evidence={ECO:0000256|ARBA:ARBA00001944};
CC -!- SUBUNIT: Interacts through its C-terminal domain (CTD) with the CTD of
CC eIF1A (EIF1AX) or with the CTD of EIF5 (mutually exclusive) through a
CC common binding site. Interacts with eIF1A (EIF1AX) from the location of
CC the start codon by the 43S complex until the formation of the 80S
CC complex. Interacts with ANXA5 in a calcium and phospholipid-dependent
CC manner. {ECO:0000256|ARBA:ARBA00061781}.
CC -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000256|ARBA:ARBA00004496}.
CC -!- SIMILARITY: Belongs to the TRAFAC class translation factor GTPase
CC superfamily. Classic translation factor GTPase family. IF-2 subfamily.
CC {ECO:0000256|ARBA:ARBA00007733}.
CC ---------------------------------------------------------------------------
CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms
CC Distributed under the Creative Commons Attribution (CC BY 4.0) License
CC ---------------------------------------------------------------------------
DR AlphaFoldDB; A0A3Q3NCG0; -.
DR STRING; 205130.ENSMAMP00000033576; -.
DR Ensembl; ENSMAMT00000034436.2; ENSMAMP00000033576.2; ENSMAMG00000022568.2.
DR GeneTree; ENSGT00940000163243; -.
DR InParanoid; A0A3Q3NCG0; -.
DR Proteomes; UP000261640; Unplaced.
DR GO; GO:0005739; C:mitochondrion; IEA:TreeGrafter.
DR GO; GO:0005525; F:GTP binding; IEA:UniProtKB-KW.
DR GO; GO:0003924; F:GTPase activity; IEA:InterPro.
DR GO; GO:0003743; F:translation initiation factor activity; IEA:UniProtKB-KW.
DR CDD; cd03703; aeIF5B_II; 1.
DR CDD; cd16266; IF2_aeIF5B_IV; 1.
DR CDD; cd01887; IF2_eIF5B; 1.
DR FunFam; 2.40.30.10:FF:000013; eukaryotic translation initiation factor 5B; 1.
DR FunFam; 2.40.30.10:FF:000026; Eukaryotic translation initiation factor 5B; 1.
DR FunFam; 3.40.50.10050:FF:000002; Eukaryotic translation initiation factor 5B; 1.
DR FunFam; 3.40.50.300:FF:000112; Eukaryotic translation initiation factor 5B; 1.
DR Gene3D; 3.40.50.300; P-loop containing nucleotide triphosphate hydrolases; 1.
DR Gene3D; 2.40.30.10; Translation factors; 2.
DR Gene3D; 3.40.50.10050; Translation initiation factor IF- 2, domain 3; 1.
DR InterPro; IPR029459; EFTU-type.
DR InterPro; IPR027417; P-loop_NTPase.
DR InterPro; IPR005225; Small_GTP-bd.
DR InterPro; IPR000795; T_Tr_GTP-bd_dom.
DR InterPro; IPR015760; TIF_IF2.
DR InterPro; IPR023115; TIF_IF2_dom3.
DR InterPro; IPR036925; TIF_IF2_dom3_sf.
DR InterPro; IPR009000; Transl_B-barrel_sf.
DR NCBIfam; NF003078; PRK04004.1; 1.
DR NCBIfam; TIGR00231; small_GTP; 1.
DR PANTHER; PTHR43381:SF4; EUKARYOTIC TRANSLATION INITIATION FACTOR 5B; 1.
DR PANTHER; PTHR43381; TRANSLATION INITIATION FACTOR IF-2-RELATED; 1.
DR Pfam; PF00009; GTP_EFTU; 1.
DR Pfam; PF14578; GTP_EFTU_D4; 1.
DR Pfam; PF11987; IF-2; 1.
DR PRINTS; PR00315; ELONGATNFCT.
DR SUPFAM; SSF52156; Initiation factor IF2/eIF5b, domain 3; 1.
DR SUPFAM; SSF52540; P-loop containing nucleoside triphosphate hydrolases; 1.
DR SUPFAM; SSF50447; Translation proteins; 1.
DR PROSITE; PS51722; G_TR_2; 1.
PE 3: Inferred from homology;
KW Cytoplasm {ECO:0000256|ARBA:ARBA00022490};
KW GTP-binding {ECO:0000256|ARBA:ARBA00023134};
KW Hydrolase {ECO:0000256|ARBA:ARBA00022801};
KW Initiation factor {ECO:0000256|ARBA:ARBA00022540};
KW Metal-binding {ECO:0000256|ARBA:ARBA00022723};
KW Nucleotide-binding {ECO:0000256|ARBA:ARBA00022741};
KW Protein biosynthesis {ECO:0000256|ARBA:ARBA00022917};
KW Reference proteome {ECO:0000313|Proteomes:UP000261640}.
FT DOMAIN 315..532
FT /note="Tr-type G"
FT /evidence="ECO:0000259|PROSITE:PS51722"
FT REGION 1..289
FT /note="Disordered"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 7..18
FT /note="Basic and acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 33..105
FT /note="Basic and acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 118..132
FT /note="Basic and acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 142..177
FT /note="Low complexity"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 183..195
FT /note="Acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 196..209
FT /note="Basic and acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 219..251
FT /note="Acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
FT COMPBIAS 272..283
FT /note="Acidic residues"
FT /evidence="ECO:0000256|SAM:MobiDB-lite"
SQ SEQUENCE 904 AA; 102500 MW; F84D521A4CB939CE CRC64;
DKKKKKGEKE KEEKEKKKGP SKATVKAMQE ALAKMKEEEE RAKREEEERL RRLEELEKQR
LEQERLEQER KEKKKQKEKE RKERLKKEGK LLTKAQREAR ARAEATLRML QAQGVEVPSK
DSVPKKKPVY GDKRKKKPNA QTPEETSEVT SPTSETPEPV TMETEAETPA AEPVSPEVKP
EAAVDDWEAI ASDEEKELKK VHIEVKEESA APPQHTGSED EDEEEDEEED EDDEEEDDDE
EEEEESEEEE EDAKKESTAA AVQGKRRAAR ESEDESSESE DDDGRTKEER LYDRAKRRIE
KRRAENMRNI NLDMLRAPVV CVLGHVDTGK TKILDKLRHT HVQDGEAGGI TQQIGATNVP
KETIEDQTRM VKNFECENIK IPGMLIIDTP GHESFSNLRN RGSSLCDIAI LVVDIMHGLE
PQTLESINLL KEKKCPFIVA LNKIDRLYDW KKSPDTDVVA TLKKQKKNTK DEFDERAKAV
IVEFAQQGLN AALFYENKDP RTFVSLVPTS AHSGDGMGNL IALLVELTQT MLARRLAHCD
ELRAQVMEVK ALPGMGTTID VILINGRLRE GETIIVPGVE GPIVTQIRGL LLPPPLKELR
VKSQYEKHKE VSTSQGVKIL GKDLEKALAG LPLLVAHRDD EVPVLRDELV RELKQTLSSI
KLEEKGVYVQ ASTLGSLEAL LEFLRTSKYA GINIGPVHKK DVMKASTMLE HDLQYAVILA
FDVKVERESQ EMADSLGVRI FSAEIIYHLF DAFTKYREDY KKAKQEEFKH IAVFPVKLRV
LPQFIFNSRD PIVMGVMVEA GVLKQGTPLC VPSKAFVDIG VVTSIEVNHK PVDSAKKGQE
ICIKIEPIPG ESPKMYGRHF EATDIIVSKI TRASIDALKN WFRDEMQKSD WQLIMELKKT
FEII
//
