ID   PSK_ASPOF               Reviewed;          75 AA.
AC   Q9FS10;
DT   29-AUG-2001, integrated into UniProtKB/Swiss-Prot.
DT   01-MAR-2001, sequence version 1.
DT   25-MAY-2022, entry version 53.
DE   RecName: Full=Phytosulfokines;
DE   Contains:
DE     RecName: Full=Phytosulfokine-alpha;
DE              Short=PSK-alpha;
DE              Short=Phytosulfokine-a;
DE   Contains:
DE     RecName: Full=Phytosulfokine-beta;
DE              Short=PSK-beta;
DE              Short=Phytosulfokine-b;
DE   Flags: Precursor;
GN   Name=PSK;
OS   Asparagus officinalis (Garden asparagus).
OC   Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC   Spermatophyta; Magnoliopsida; Liliopsida; Asparagales; Asparagaceae;
OC   Asparagoideae; Asparagus.
OX   NCBI_TaxID=4686;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RA   Matsubayashi Y., Goto T., Sakagami Y.;
RT   "Asparagus preprophytosulfokine.";
RL   Submitted (OCT-1999) to the EMBL/GenBank/DDBJ databases.
RN   [2]
RP   PROTEIN SEQUENCE OF 67-71, AND SULFATION AT TYR-67 AND TYR-69.
RX   PubMed=8755525; DOI=10.1073/pnas.93.15.7623;
RA   Matsubayashi Y., Sakagami Y.;
RT   "Phytosulfokine, sulfated peptides that induce the proliferation of single
RT   mesophyll cells of Asparagus officinalis L.";
RL   Proc. Natl. Acad. Sci. U.S.A. 93:7623-7627(1996).
RN   [3]
RP   PROTEIN SEQUENCE OF 67-71, MUTAGENESIS OF ILE-68, AND CHARACTERIZATION.
RX   PubMed=8769119; DOI=10.1006/bbrc.1996.1155;
RA   Matsubayashi Y., Hanai H., Hara O., Sakagami Y.;
RT   "Active fragments and analogs of the plant growth factor, phytosulfokine:
RT   structure-activity relationships.";
RL   Biochem. Biophys. Res. Commun. 225:209-214(1996).
CC   -!- FUNCTION: Promotes plant cell differentiation, organogenesis and
CC       somatic embryogenesis as well as cell proliferation.
CC   -!- SUBCELLULAR LOCATION: Secreted.
CC   -!- INDUCTION: Expression is regulated by a signal transduction pathway
CC       activated by auxin and cytokinin.
CC   -!- PTM: Sulfation is important for activity and for the binding to a
CC       putative membrane receptor. Deletion of the sulfate groups of Tyr-67
CC       and Tyr-69 resulted in compounds with respectively 0.6% and 4% of the
CC       activity. {ECO:0000269|PubMed:8755525}.
CC   -!- PTM: PSK-alpha is produced by endopeptidase digestion. PSK-beta is
CC       produced from PSK-alpha by exopeptidase digestion.
CC   -!- MISCELLANEOUS: The N-terminal tripeptide (YIY) is the active core.
CC   -!- SIMILARITY: Belongs to the phytosulfokine family. {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   EMBL; AB033828; BAB20706.1; -; mRNA.
DR   PIR; JT0870; JT0870.
DR   AlphaFoldDB; Q9FS10; -.
DR   GO; GO:0005576; C:extracellular region; IEA:UniProtKB-SubCell.
DR   GO; GO:0008083; F:growth factor activity; IEA:UniProtKB-KW.
DR   GO; GO:0030154; P:cell differentiation; IEA:UniProtKB-KW.
DR   GO; GO:0008283; P:cell population proliferation; IEA:InterPro.
DR   InterPro; IPR009438; Phytosulfokine.
DR   PANTHER; PTHR33285; PTHR33285; 1.
DR   Pfam; PF06404; PSK; 1.
PE   1: Evidence at protein level;
KW   Developmental protein; Differentiation; Direct protein sequencing;
KW   Growth factor; Secreted; Signal; Sulfation.
FT   SIGNAL          1..22
FT                   /evidence="ECO:0000255"
FT   PROPEP          23..66
FT                   /evidence="ECO:0000255"
FT                   /id="PRO_0000024056"
FT   PEPTIDE         67..71
FT                   /note="Phytosulfokine-alpha"
FT                   /id="PRO_0000024057"
FT   PEPTIDE         67..70
FT                   /note="Phytosulfokine-beta"
FT                   /id="PRO_0000024058"
FT   PROPEP          72..75
FT                   /evidence="ECO:0000255"
FT                   /id="PRO_0000024059"
FT   MOD_RES         67
FT                   /note="Sulfotyrosine"
FT                   /evidence="ECO:0000269|PubMed:8755525"
FT   MOD_RES         69
FT                   /note="Sulfotyrosine"
FT                   /evidence="ECO:0000269|PubMed:8755525"
FT   MUTAGEN         68
FT                   /note="I->V: Activity decreased 20-fold."
FT                   /evidence="ECO:0000269|PubMed:8769119"
SQ   SEQUENCE   75 AA;  8274 MW;  E93F7A982361E071 CRC64;
     MSSKAITLLL IALLFSLSLA QAARPLQPAD STKSVHVIPE KVHDEACEGV GEEECLMRRT
     LTAHVDYIYT QDHNP