ID   CAPSD_BPPRR             Reviewed;         131 AA.
AC   P03616;
DT   21-JUL-1986, integrated into UniProtKB/Swiss-Prot.
DT   21-JUL-1986, sequence version 1.
DT   28-JUN-2023, entry version 68.
DE   RecName: Full=Capsid protein;
DE            Short=CP;
DE   AltName: Full=Coat protein;
OS   Pseudomonas phage PRR1 (Bacteriophage PRR1).
OC   Viruses; Riboviria; Orthornavirae; Lenarviricota; Leviviricetes;
OC   Norzivirales; Fiersviridae; Perrunavirus; Perrunavirus olsenii.
OX   NCBI_TaxID=12024;
OH   NCBI_TaxID=286; Pseudomonas.
RN   [1]
RP   PROTEIN SEQUENCE.
RX   PubMed=107028; DOI=10.1111/j.1432-1033.1979.tb12903.x;
RA   Dhaese P., Vandekerckhove J., van Montagu M.;
RT   "The primary structure of the coat protein of the broad-host-range RNA
RT   bacteriophage PRR1.";
RL   Eur. J. Biochem. 94:375-386(1979).
RN   [2] {ECO:0007744|PDB:2VF9}
RP   X-RAY CRYSTALLOGRAPHY (3.50 ANGSTROMS), AND SUBUNIT.
RX   PubMed=18786545; DOI=10.1016/j.jmb.2008.08.060;
RA   Persson M., Tars K., Liljas L.;
RT   "The capsid of the small RNA phage PRR1 is stabilized by metal ions.";
RL   J. Mol. Biol. 383:914-922(2008).
RN   [3] {ECO:0007744|PDB:4ANG}
RP   X-RAY CRYSTALLOGRAPHY (3.50 ANGSTROMS) IN COMPLEX WITH RNA, RNA-BINDING,
RP   FUNCTION, AND SUBUNIT.
RX   PubMed=23519411; DOI=10.1107/s0907444912047464;
RA   Persson M., Tars K., Liljas L.;
RT   "PRR1 coat protein binding to its RNA translational operator.";
RL   Acta Crystallogr. D 69:367-372(2013).
CC   -!- FUNCTION: Capsid protein self-assembles to form an icosahedral capsid
CC       with a T=3 symmetry, about 26 nm in diameter, and consisting of 89
CC       capsid proteins dimers (178 capsid proteins). Involved in viral genome
CC       encapsidation through the interaction between a capsid protein dimer
CC       and the multiple packaging signals present in the RNA genome. The
CC       capsid contains also 1 copy of the A2 maturation protein.
CC       {ECO:0000250|UniProtKB:P03612}.
CC   -!- FUNCTION: Acts as a translational repressor of viral replicase
CC       synthesis late in infection. This latter function is the result of
CC       capsid protein interaction with an RNA hairpin which contains the
CC       replicase ribosome-binding site. {ECO:0000250|UniProtKB:P03612,
CC       ECO:0000305|PubMed:23519411}.
CC   -!- SUBUNIT: Homodimer (PubMed:18786545, PubMed:23519411). The capsid
CC       proteins form dimers that assemble by group of 5. Twelve such pentamers
CC       are linked together with free dimers. The homodimers binds to the viral
CC       RNA via an operator hairpin, but also to many other RNA sequences in
CC       the viral genome; this interaction probably shifts the virus from the
CC       replicative to the assembly phase and ensures specific encapsidation of
CC       the viral genome. {ECO:0000250|UniProtKB:P03612,
CC       ECO:0000269|PubMed:18786545, ECO:0000269|PubMed:23519411}.
CC   -!- SUBCELLULAR LOCATION: Virion {ECO:0000250|UniProtKB:P03612}. Note=The
CC       shell is composed of 178 copies of the capsid protein and 1 copy of the
CC       maturation protein. {ECO:0000250|UniProtKB:P03612}.
CC   -!- SIMILARITY: Belongs to the Leviviricetes capsid protein family.
CC       {ECO:0000305}.
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   PIR; A04225; VCBPP1.
DR   PDB; 2VF9; X-ray; 3.50 A; A/B/C=1-131.
DR   PDB; 4ANG; X-ray; 3.50 A; A/B/C=1-131.
DR   PDBsum; 2VF9; -.
DR   PDBsum; 4ANG; -.
DR   SMR; P03616; -.
DR   EvolutionaryTrace; P03616; -.
DR   GO; GO:0039617; C:T=3 icosahedral viral capsid; IEA:UniProtKB-KW.
DR   GO; GO:0003723; F:RNA binding; IEA:UniProtKB-KW.
DR   GO; GO:0005198; F:structural molecule activity; IEA:InterPro.
DR   Gene3D; 3.30.380.10; MS2 Viral Coat Protein; 1.
DR   InterPro; IPR002703; Levivir_coat.
DR   InterPro; IPR015954; Phage_RNA-type_capsid.
DR   Pfam; PF01819; Levi_coat; 1.
DR   SUPFAM; SSF55405; RNA bacteriophage capsid protein; 1.
PE   1: Evidence at protein level;
KW   3D-structure; Capsid protein; Direct protein sequencing; RNA-binding;
KW   T=3 icosahedral capsid protein; Virion.
FT   CHAIN           1..131
FT                   /note="Capsid protein"
FT                   /id="PRO_0000164845"
FT   BINDING         2
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /ligand_note="structural"
FT                   /evidence="ECO:0000269|PubMed:18786545,
FT                   ECO:0000269|PubMed:23519411"
FT   BINDING         131
FT                   /ligand="Ca(2+)"
FT                   /ligand_id="ChEBI:CHEBI:29108"
FT                   /ligand_note="structural"
FT                   /evidence="ECO:0000269|PubMed:18786545,
FT                   ECO:0000269|PubMed:23519411"
FT   STRAND          6..9
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   STRAND          12..14
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   STRAND          17..34
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   STRAND          36..41
FT                   /evidence="ECO:0007829|PDB:4ANG"
FT   STRAND          43..51
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   STRAND          55..73
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   STRAND          76..94
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   HELIX           99..112
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   STRAND          113..116
FT                   /evidence="ECO:0007829|PDB:2VF9"
FT   HELIX           118..124
FT                   /evidence="ECO:0007829|PDB:2VF9"
SQ   SEQUENCE   131 AA;  14536 MW;  E7E639E1E50FC612 CRC64;
     AQLQNLVLKD REATPNDHTF VPRDIRDNVG EVVESTGVPI GESRFTISLR KTSNGRYKST
     LKLVVPVVQS QTVNGIVTPV VVRTSYVTVD FDYDARSTTK ERNNFVGMIA DALKADLMLV
     HDTIVNLQGV Y
//