ID   SSRP_SYNJB              Reviewed;         154 AA.
AC   Q2JM08;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   07-MAR-2006, sequence version 1.
DT   25-MAY-2022, entry version 89.
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=CYB_1264;
OS   Synechococcus sp. (strain JA-2-3B'a(2-13)) (Cyanobacteria bacterium
OS   Yellowstone B-Prime).
OC   Bacteria; Cyanobacteria; Synechococcales; Synechococcaceae; Synechococcus;
OC   unclassified Synechococcus.
OX   NCBI_TaxID=321332;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=JA-2-3B'a(2-13);
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; CP000240; ABD02239.1; -; Genomic_DNA.
DR   RefSeq; WP_011432891.1; NC_007776.1.
DR   AlphaFoldDB; Q2JM08; -.
DR   SMR; Q2JM08; -.
DR   STRING; 321332.CYB_1264; -.
DR   KEGG; cyb:CYB_1264; -.
DR   eggNOG; COG0691; Bacteria.
DR   HOGENOM; CLU_108953_0_1_3; -.
DR   OMA; WTNHSAR; -.
DR   OrthoDB; 1720952at2; -.
DR   Proteomes; UP000001938; 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; Reference proteome; RNA-binding.
FT   CHAIN           1..154
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_1000002175"
FT   REGION          134..154
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
SQ   SEQUENCE   154 AA;  17940 MW;  2DB187E378366714 CRC64;
     MAVDPNVKTL VDNRRARFEY DILETYEAGI QLTGTEVKSI RAGKANLQDA FALFRDGEAW
     LHNLHISPHD TASKVFNHDP TRRRKLLLHR REIDRLRGLV EQKGLTVVPL KLVLNRGWIK
     AHLGVARGKK LHDKRQAIKE RQTQREIQRE LKER