ID   UBIQ_HELAN              Reviewed;          77 AA.
AC   P69313; O82079; P03993;
DT   23-OCT-1986, integrated into UniProtKB/Swiss-Prot.
DT   10-AUG-2010, sequence version 2.
DT   03-AUG-2022, entry version 51.
DE   RecName: Full=Ubiquitin;
DE   Flags: Precursor;
OS   Helianthus annuus (Common sunflower).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC   asterids; campanulids; Asterales; Asteraceae; Asteroideae;
OC   Heliantheae alliance; Heliantheae; Helianthus.
OX   NCBI_TaxID=4232;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   STRAIN=cv. HA401B / Cargill;
RX   PubMed=2538802; DOI=10.1093/nar/17.5.2119;
RA   Binet M.N., Steinmetz A., Tessier L.H.;
RT   "The primary structure of sunflower (Helianthus annuus) ubiquitin.";
RL   Nucleic Acids Res. 17:2119-2119(1989).
CC   -!- FUNCTION: Ubiquitin exists either covalently attached to another
CC       protein, or free (unanchored). When covalently bound, it is conjugated
CC       to target proteins via an isopeptide bond either as a monomer
CC       (monoubiquitin), a polymer linked via different Lys residues of the
CC       ubiquitin (polyubiquitin chains) or a linear polymer linked via the
CC       initiator Met of the ubiquitin (linear polyubiquitin chains).
CC       Polyubiquitin chains, when attached to a target protein, have different
CC       functions depending on the Lys residue of the ubiquitin that is linked:
CC       Lys-48-linked is involved in protein degradation via the proteasome.
CC       Linear polymer chains formed via attachment by the initiator Met lead
CC       to cell signaling. Ubiquitin is usually conjugated to Lys residues of
CC       target proteins, however, in rare cases, conjugation to Cys or Ser
CC       residues has been observed. When polyubiquitin is free (unanchored-
CC       polyubiquitin), it also has distinct roles, such as in activation of
CC       protein kinases, and in signaling (By similarity). {ECO:0000250}.
CC   -!- SUBCELLULAR LOCATION: Cytoplasm {ECO:0000250}. Nucleus {ECO:0000250}.
CC   -!- SIMILARITY: Belongs to the ubiquitin family. {ECO:0000305}.
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DR   EMBL; X14333; CAA32511.1; -; mRNA.
DR   PIR; S03599; UQFS.
DR   AlphaFoldDB; P69313; -.
DR   SMR; P69313; -.
DR   GO; GO:0005737; C:cytoplasm; IEA:UniProtKB-SubCell.
DR   GO; GO:0005634; C:nucleus; IEA:UniProtKB-SubCell.
DR   GO; GO:0003729; F:mRNA binding; IEA:UniProt.
DR   InterPro; IPR000626; Ubiquitin-like_dom.
DR   InterPro; IPR029071; Ubiquitin-like_domsf.
DR   InterPro; IPR019954; Ubiquitin_CS.
DR   InterPro; IPR019956; Ubiquitin_dom.
DR   Pfam; PF00240; ubiquitin; 1.
DR   PRINTS; PR00348; UBIQUITIN.
DR   SMART; SM00213; UBQ; 1.
DR   SUPFAM; SSF54236; SSF54236; 1.
DR   PROSITE; PS00299; UBIQUITIN_1; 1.
DR   PROSITE; PS50053; UBIQUITIN_2; 1.
PE   3: Inferred from homology;
KW   Cytoplasm; Isopeptide bond; Nucleus; Ubl conjugation.
FT   CHAIN           1..76
FT                   /note="Ubiquitin"
FT                   /id="PRO_0000114840"
FT   PROPEP          77
FT                   /id="PRO_0000396429"
FT   DOMAIN          1..76
FT                   /note="Ubiquitin-like"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00214"
FT   CROSSLNK        48
FT                   /note="Glycyl lysine isopeptide (Lys-Gly) (interchain with
FT                   G-Cter in ubiquitin)"
FT                   /evidence="ECO:0000250"
FT   CROSSLNK        76
FT                   /note="Glycyl lysine isopeptide (Gly-Lys) (interchain with
FT                   K-? in acceptor proteins)"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00214"
SQ   SEQUENCE   77 AA;  8672 MW;  4C052936277CD840 CRC64;
     MQIFVKTLTG KTITLEVESS DTIDNVKAKI QDKEGIPPDQ QRLIFAGKQL EDGRTLADYN
     IQKESTLHLV LRLRGGF