ID   SSRP_TRIV2              Reviewed;         155 AA.
AC   Q3MAP3;
DT   15-JAN-2008, integrated into UniProtKB/Swiss-Prot.
DT   25-OCT-2005, sequence version 1.
DT   25-MAY-2022, entry version 90.
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=Ava_2325;
OS   Trichormus variabilis (strain ATCC 29413 / PCC 7937) (Anabaena variabilis).
OC   Bacteria; Cyanobacteria; Nostocales; Nostocaceae; Trichormus.
OX   NCBI_TaxID=240292;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=ATCC 29413 / PCC 7937;
RX   PubMed=25197444; DOI=10.4056/sigs.3899418;
RA   Thiel T., Pratte B.S., Zhong J., Goodwin L., Copeland A., Lucas S., Han C.,
RA   Pitluck S., Land M.L., Kyrpides N.C., Woyke T.;
RT   "Complete genome sequence of Anabaena variabilis ATCC 29413.";
RL   Stand. Genomic Sci. 9:562-573(2014).
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}.
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   EMBL; CP000117; ABA21943.1; -; Genomic_DNA.
DR   AlphaFoldDB; Q3MAP3; -.
DR   SMR; Q3MAP3; -.
DR   STRING; 240292.Ava_2325; -.
DR   EnsemblBacteria; ABA21943; ABA21943; Ava_2325.
DR   KEGG; ava:Ava_2325; -.
DR   eggNOG; COG0691; Bacteria.
DR   HOGENOM; CLU_108953_0_1_3; -.
DR   OMA; WTNHSAR; -.
DR   Proteomes; UP000002533; 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..155
FT                   /note="SsrA-binding protein"
FT                   /id="PRO_1000001993"
FT   REGION          135..155
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
SQ   SEQUENCE   155 AA;  18155 MW;  ECB50C4ECC8FB3A2 CRC64;
     MSDKSESYKV ITDNRQARYL YEILETFEAG IQLTGTEVKS IRAGKVNLQD GYALLRDGEI
     WLINAHISPY NASGQYFNHE PRRTRKLLLH RQEIRKLIGK VEQQGLTLVP LKMYLKRGWV
     KVSIALGKGK KLHDKRESLK RRQDQRDIQR AMKNY