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Protein

Platelet factor 4

Gene

PF4

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: -Experimental evidence at protein leveli

Functioni

Released during platelet aggregation. Neutralizes the anticoagulant effect of heparin because it binds more strongly to heparin than to the chondroitin-4-sulfate chains of the carrier molecule. Chemotactic for neutrophils and monocytes. Inhibits endothelial cell proliferation, the short form is a more potent inhibitor than the longer form.1 Publication

GO - Molecular functioni

  • chemokine activity Source: UniProtKB
  • CXCR3 chemokine receptor binding Source: UniProtKB
  • heparin binding Source: UniProtKB

GO - Biological processi

  • antimicrobial humoral immune response mediated by antimicrobial peptide Source: UniProtKB
  • chemokine-mediated signaling pathway Source: GO_Central
  • cytokine-mediated signaling pathway Source: UniProtKB
  • defense response to protozoan Source: UniProtKB
  • G-protein coupled receptor signaling pathway Source: GO_Central
  • immune response Source: GO_Central
  • inflammatory response Source: GO_Central
  • killing by host of symbiont cells Source: UniProtKB
  • killing of cells of other organism Source: UniProtKB
  • leukocyte chemotaxis Source: UniProtKB
  • negative regulation of angiogenesis Source: UniProtKB
  • negative regulation of cytolysis Source: BHF-UCL
  • negative regulation of extrinsic apoptotic signaling pathway in absence of ligand Source: BHF-UCL
  • negative regulation of megakaryocyte differentiation Source: UniProtKB
  • negative regulation of MHC class II biosynthetic process Source: BHF-UCL
  • platelet activation Source: UniProtKB
  • platelet degranulation Source: Reactome
  • positive regulation of cAMP-mediated signaling Source: UniProtKB
  • positive regulation of cAMP metabolic process Source: UniProtKB
  • positive regulation of gene expression Source: BHF-UCL
  • positive regulation of macrophage derived foam cell differentiation Source: BHF-UCL
  • positive regulation of macrophage differentiation Source: BHF-UCL
  • positive regulation of neutrophil chemotaxis Source: GO_Central
  • positive regulation of transcription by RNA polymerase II Source: UniProtKB
  • positive regulation of tumor necrosis factor production Source: BHF-UCL
  • regulation of cell proliferation Source: UniProtKB
  • regulation of megakaryocyte differentiation Source: Reactome
  • response to lipopolysaccharide Source: GO_Central

Keywordsi

Molecular functionCytokine, Heparin-binding
Biological processChemotaxis

Enzyme and pathway databases

ReactomeiR-HSA-114608 Platelet degranulation
R-HSA-140875 Common Pathway of Fibrin Clot Formation
R-HSA-202733 Cell surface interactions at the vascular wall
R-HSA-380108 Chemokine receptors bind chemokines
R-HSA-418594 G alpha (i) signalling events
R-HSA-8936459 RUNX1 regulates genes involved in megakaryocyte differentiation and platelet function

Names & Taxonomyi

Protein namesi
Recommended name:
Platelet factor 4
Short name:
PF-4
Alternative name(s):
C-X-C motif chemokine 4
Iroplact
Oncostatin-A
Cleaved into the following chain:
Alternative name(s):
Endothelial cell growth inhibitor1 Publication
Gene namesi
Name:PF4
Synonyms:CXCL4, SCYB4
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 4

Organism-specific databases

EuPathDBiHostDB:ENSG00000163737.3
HGNCiHGNC:8861 PF4
MIMi173460 gene
neXtProtiNX_P02776

Subcellular locationi

Extracellular region or secreted Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi apparatus Nucleus Mitochondrion Manual annotation Automatic computational assertionGraphics by Christian Stolte; Source: COMPARTMENTS

Keywords - Cellular componenti

Secreted

Pathology & Biotechi

Organism-specific databases

DisGeNETi5196
OpenTargetsiENSG00000163737
PharmGKBiPA33203

Chemistry databases

ChEMBLiCHEMBL3286075
DrugBankiDB00055 Drotrecogin alfa

Polymorphism and mutation databases

BioMutaiPF4
DMDMi130304

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Signal peptidei1 – 315 PublicationsAdd BLAST31
ChainiPRO_000000506832 – 101Platelet factor 4Add BLAST70
ChainiPRO_000035121748 – 101Platelet factor 4, short form1 PublicationAdd BLAST54

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Disulfide bondi41 ↔ 671 Publication
Disulfide bondi43 ↔ 831 Publication
Modified residuei57PhosphoserineBy similarity1

Keywords - PTMi

Disulfide bond, Phosphoprotein

Proteomic databases

PaxDbiP02776
PeptideAtlasiP02776
PRIDEiP02776
ProteomicsDBi51593
TopDownProteomicsiP02776

2D gel databases

OGPiP02776

PTM databases

PhosphoSitePlusiP02776

Miscellaneous databases

PMAP-CutDBiP02776

Expressioni

Gene expression databases

BgeeiENSG00000163737
CleanExiHS_PF4
GenevisibleiP02776 HS

Organism-specific databases

HPAiCAB026008
HPA052485

Interactioni

Subunit structurei

Homotetramer.2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
APOHP027492EBI-2565740,EBI-2114682

GO - Molecular functioni

  • chemokine activity Source: UniProtKB
  • CXCR3 chemokine receptor binding Source: UniProtKB

Protein-protein interaction databases

BioGridi111219, 9 interactors
DIPiDIP-56941N
IntActiP02776, 5 interactors
MINTiP02776
STRINGi9606.ENSP00000296029

Chemistry databases

BindingDBiP02776

Structurei

Secondary structure

1101
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi38 – 40Combined sources3
Beta strandi42 – 44Combined sources3
Helixi52 – 54Combined sources3
Beta strandi55 – 61Combined sources7
Beta strandi64 – 66Combined sources3
Beta strandi67 – 69Combined sources3
Beta strandi71 – 76Combined sources6
Beta strandi77 – 79Combined sources3
Beta strandi81 – 83Combined sources3
Beta strandi86 – 88Combined sources3
Helixi90 – 99Combined sources10

3D structure databases

ProteinModelPortaliP02776
SMRiP02776
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP02776

Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni92 – 98Heparin-binding7

Sequence similaritiesi

Keywords - Domaini

Signal

Phylogenomic databases

eggNOGiENOG410J314 Eukaryota
ENOG4111556 LUCA
GeneTreeiENSGT00910000144355
HOGENOMiHOG000220915
HOVERGENiHBG107789
InParanoidiP02776
KOiK05407
OMAiGAGLHCP
OrthoDBiEOG091G14JD
PhylomeDBiP02776
TreeFamiTF333433

Family and domain databases

CDDicd00273 Chemokine_CXC, 1 hit
InterProiView protein in InterPro
IPR001089 Chemokine_CXC
IPR018048 Chemokine_CXC_CS
IPR001811 Chemokine_IL8-like_dom
IPR033899 CXC_Chemokine_domain
IPR036048 Interleukin_8-like_sf
IPR027222 PF4
PANTHERiPTHR10179 PTHR10179, 1 hit
PTHR10179:SF38 PTHR10179:SF38, 1 hit
PfamiView protein in Pfam
PF00048 IL8, 1 hit
PRINTSiPR00437 SMALLCYTKCXC
SMARTiView protein in SMART
SM00199 SCY, 1 hit
SUPFAMiSSF54117 SSF54117, 1 hit
PROSITEiView protein in PROSITE
PS00471 SMALL_CYTOKINES_CXC, 1 hit

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

P02776-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MSSAAGFCAS RPGLLFLGLL LLPLVVAFAS AEAEEDGDLQ CLCVKTTSQV
60 70 80 90 100
RPRHITSLEV IKAGPHCPTA QLIATLKNGR KICLDLQAPL YKKIIKKLLE

S
Length:101
Mass (Da):10,845
Last modified:July 1, 1989 - v2
Checksum:iE96C2EFE9B944D85
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti78N → D AA sequence (PubMed:267922).Curated1
Sequence conflicti78N → D AA sequence (PubMed:601757).Curated1

Mass spectrometryi

Molecular mass is 7765 Da from positions 32 - 101. Determined by ESI. 1 Publication
Molecular mass is 6033 Da from positions 48 - 101. Determined by ESI. Short form.1 Publication

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M25897 mRNA Translation: AAA60066.1
AF349466 Genomic DNA Translation: AAK29643.1
CR407677 mRNA Translation: CAG28605.1
AC097709 Genomic DNA Translation: AAY41003.1
BC093965 mRNA Translation: AAH93965.1
BC112093 mRNA Translation: AAI12094.1
CCDSiCCDS3562.1
PIRiA60161 PFHU4
RefSeqiNP_002610.1, NM_002619.3
UniGeneiHs.81564

Genome annotation databases

EnsembliENST00000296029; ENSP00000296029; ENSG00000163737
GeneIDi5196
KEGGihsa:5196
UCSCiuc003hhi.4 human

Similar proteinsi

Entry informationi

Entry nameiPLF4_HUMAN
AccessioniPrimary (citable) accession number: P02776
Secondary accession number(s): Q53X61, Q9UC64, Q9UC65
Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 1, 1989
Last modified: June 20, 2018
This is version 181 of the entry and version 2 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 4
    Human chromosome 4: entries, gene names and cross-references to MIM
  2. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  3. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  4. SIMILARITY comments
    Index of protein domains and families

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