ID   SSRP_SYNJA              Reviewed;         154 AA.
AC   Q2JV45;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   07-MAR-2006, sequence version 1.
DT   25-MAY-2022, entry version 87.
DE   RecName: Full=SsrA-binding protein {ECO:0000255|HAMAP-Rule:MF_00023};
DE   AltName: Full=Small protein B {ECO:0000255|HAMAP-Rule:MF_00023};
GN   Name=smpB {ECO:0000255|HAMAP-Rule:MF_00023}; OrderedLocusNames=CYA_1218;
OS   Synechococcus sp. (strain JA-3-3Ab) (Cyanobacteria bacterium Yellowstone
OS   A-Prime).
OC   Bacteria; Cyanobacteria; Synechococcales; Synechococcaceae; Synechococcus;
OC   unclassified Synechococcus.
OX   NCBI_TaxID=321327;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=JA-3-3Ab;
RX   PubMed=18059494; DOI=10.1038/ismej.2007.46;
RA   Bhaya D., Grossman A.R., Steunou A.-S., Khuri N., Cohan F.M., Hamamura N.,
RA   Melendrez M.C., Bateson M.M., Ward D.M., Heidelberg J.F.;
RT   "Population level functional diversity in a microbial community revealed by
RT   comparative genomic and metagenomic analyses.";
RL   ISME J. 1:703-713(2007).
CC   -!- FUNCTION: Required for rescue of stalled ribosomes mediated by trans-
CC       translation. Binds to transfer-messenger RNA (tmRNA), required for
CC       stable association of tmRNA with ribosomes. tmRNA and SmpB together
CC       mimic tRNA shape, replacing the anticodon stem-loop with SmpB. tmRNA is
CC       encoded by the ssrA gene; the 2 termini fold to resemble tRNA(Ala) and
CC       it encodes a 'tag peptide', a short internal open reading frame. During
CC       trans-translation Ala-aminoacylated tmRNA acts like a tRNA, entering
CC       the A-site of stalled ribosomes, displacing the stalled mRNA. The
CC       ribosome then switches to translate the ORF on the tmRNA; the nascent
CC       peptide is terminated with the 'tag peptide' encoded by the tmRNA and
CC       targeted for degradation. The ribosome is freed to recommence
CC       translation, which seems to be the essential function of trans-
CC       translation. {ECO:0000255|HAMAP-Rule:MF_00023}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_00023}.
CC       Note=The tmRNA-SmpB complex associates with stalled 70S ribosomes.
CC       {ECO:0000255|HAMAP-Rule:MF_00023}.
CC   -!- SIMILARITY: Belongs to the SmpB family. {ECO:0000255|HAMAP-
CC       Rule:MF_00023}.
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DR   EMBL; CP000239; ABC99402.1; -; Genomic_DNA.
DR   RefSeq; WP_011430083.1; NC_007775.1.
DR   AlphaFoldDB; Q2JV45; -.
DR   SMR; Q2JV45; -.
DR   STRING; 321327.CYA_1218; -.
DR   EnsemblBacteria; ABC99402; ABC99402; CYA_1218.
DR   KEGG; cya:CYA_1218; -.
DR   eggNOG; COG0691; Bacteria.
DR   HOGENOM; CLU_108953_0_1_3; -.
DR   OMA; WTNHSAR; -.
DR   OrthoDB; 1720952at2; -.
DR   Proteomes; UP000008818; Chromosome.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0003723; F:RNA binding; IEA:UniProtKB-UniRule.
DR   GO; GO:0070929; P:trans-translation; IEA:UniProtKB-UniRule.
DR   CDD; cd09294; SmpB; 1.
DR   Gene3D; 2.40.280.10; -; 1.
DR   HAMAP; MF_00023; SmpB; 1.
DR   InterPro; IPR023620; SmpB.
DR   InterPro; IPR000037; SsrA-bd_prot.
DR   InterPro; IPR020081; SsrA-bd_prot_CS.
DR   PANTHER; PTHR30308; PTHR30308; 1.
DR   Pfam; PF01668; SmpB; 1.
DR   SUPFAM; SSF74982; SSF74982; 1.
DR   TIGRFAMs; TIGR00086; smpB; 1.
DR   PROSITE; PS01317; SSRP; 1.
PE   3: Inferred from homology;
KW   Cytoplasm; RNA-binding.
FT   CHAIN           1..154
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_1000002174"
SQ   SEQUENCE   154 AA;  17865 MW;  C79698F01CD61D07 CRC64;
     MAVDPNVKTL VENRRARFEY EILETYEAGI QLTGTEVKSI RAGKANLQDA FALFRDGEAW
     LHNLHVAPHG TASKVFNHDP TRRRKLLLHR REIDRLRGLV EQKGLTVVPL RLVLNRGWIK
     AHLGVARGKK LHDKRQAIKE RETRREIQRE LKGR