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UniProtKB - P35900 (K1C20_HUMAN)
Protein
Keratin, type I cytoskeletal 20
Gene
KRT20
Organism
Homo sapiens (Human)
Status
Functioni
Plays a significant role in maintaining keratin filament organization in intestinal epithelia. When phosphorylated, plays a role in the secretion of mucin in the small intestine (By similarity).
By similarity2 PublicationsMiscellaneous
There are two types of cytoskeletal and microfibrillar keratin: I (acidic; 40-55 kDa) and II (neutral to basic; 56-70 kDa).
GO - Molecular functioni
- structural constituent of cytoskeleton Source: UniProtKB
GO - Biological processi
- apoptotic process Source: UniProtKB-KW
- cellular response to starvation Source: Ensembl
- epithelial cell differentiation Source: GO_Central
- intermediate filament organization Source: UniProtKB
- regulation of protein secretion Source: Ensembl
Keywordsi
Biological process | Apoptosis |
Enzyme and pathway databases
PathwayCommonsi | P35900 |
Reactomei | R-HSA-6805567, Keratinization R-HSA-6809371, Formation of the cornified envelope |
SignaLinki | P35900 |
SIGNORi | P35900 |
Names & Taxonomyi
Protein namesi | Recommended name: Keratin, type I cytoskeletal 20Alternative name(s): Cytokeratin-20 Short name: CK-20 Keratin-20 Short name: K20 Protein IT |
Gene namesi | Name:KRT20 |
Organismi | Homo sapiens (Human) |
Taxonomic identifieri | 9606 [NCBI] |
Taxonomic lineagei | Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo |
Proteomesi |
|
Organism-specific databases
HGNCi | HGNC:20412, KRT20 |
MIMi | 608218, gene |
neXtProti | NX_P35900 |
VEuPathDBi | HostDB:ENSG00000171431 |
Subcellular locationi
Cytoplasm and Cytosol
- Cytoplasm 2 Publications
Cytoskeleton
- cytoskeleton Source: GO_Central
- intermediate filament Source: UniProtKB
Cytosol
- cytosol Source: HPA
Other locations
- cytoplasm Source: UniProtKB
Keywords - Cellular componenti
Cytoplasm, Intermediate filament, KeratinPathology & Biotechi
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 13 | S → A: Promotes keratin filament disassembly. 1 Publication | 1 | |
Mutagenesisi | 14 | S → A: No effect on keratin filament organization. 1 Publication | 1 | |
Mutagenesisi | 80 | R → H: Leads to collapsed filaments. 1 Publication | 1 |
Organism-specific databases
DisGeNETi | 54474 |
OpenTargetsi | ENSG00000171431 |
PharmGKBi | PA134938907 |
Miscellaneous databases
Pharosi | P35900, Tbio |
Genetic variation databases
BioMutai | KRT20 |
DMDMi | 547750 |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000063675 | 1 – 424 | Keratin, type I cytoskeletal 20Add BLAST | 424 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Modified residuei | 13 | Phosphoserine; by MAPKAPK2, MAPKAPK3 and PKC1 Publication | 1 |
Post-translational modificationi
Hyperphosphorylation at Ser-13 occurs during the early stages of apoptosis but becomes less prominent during the later stages. Phosphorylation at Ser-13 also increases in response to stress brought on by cell injury (By similarity).By similarity
Proteolytically cleaved by caspases during apoptosis. Cleavage occurs at Asp-228.1 Publication
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sitei | 228 – 229 | Cleavage; by caspases1 Publication | 2 |
Keywords - PTMi
PhosphoproteinProteomic databases
jPOSTi | P35900 |
MassIVEi | P35900 |
PaxDbi | P35900 |
PeptideAtlasi | P35900 |
PRIDEi | P35900 |
ProteomicsDBi | 55160 |
PTM databases
iPTMneti | P35900 |
PhosphoSitePlusi | P35900 |
SwissPalmi | P35900 |
Expressioni
Tissue specificityi
Expressed predominantly in the intestinal epithelium. Expressed in luminal cells of colonic mucosa. Also expressed in the Merkel cells of keratinized oral mucosa; specifically at the tips of some rete ridges of the gingival mucosa, in the basal layer of the palatal mucosa and in the taste buds of lingual mucosa.2 Publications
Developmental stagei
First detected at embryonic week 8 in individual 'converted' simple epithelial cells of the developing intestinal mucosa. In later fetal stages, synthesis extends over most goblet cells and a variable number of villus enterocytes. In the developing gastric and intestinal mucosa, expressed in all enterocytes and goblet cells as well as certain 'low-differentiated' columnar cells, whereas the neuroendocrine and Paneth cells are negative.1 Publication
Gene expression databases
Bgeei | ENSG00000171431, Expressed in colon and 106 other tissues |
Genevisiblei | P35900, HS |
Organism-specific databases
HPAi | ENSG00000171431, Tissue enriched (intestine) |
Interactioni
Subunit structurei
Heterotetramer of two type I and two type II keratins. Associates with KRT8.
Binary interactionsi
P35900
Protein-protein interaction databases
BioGRIDi | 119979, 50 interactors |
IntActi | P35900, 47 interactors |
MINTi | P35900 |
STRINGi | 9606.ENSP00000167588 |
Miscellaneous databases
RNActi | P35900, protein |
Family & Domainsi
Domains and Repeats
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Domaini | 70 – 381 | IF rodPROSITE-ProRule annotationAdd BLAST | 312 |
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 1 – 69 | HeadAdd BLAST | 69 | |
Regioni | 70 – 105 | Coil 1AAdd BLAST | 36 | |
Regioni | 106 – 123 | Linker 1Add BLAST | 18 | |
Regioni | 124 – 215 | Coil 1BAdd BLAST | 92 | |
Regioni | 216 – 238 | Linker 12Add BLAST | 23 | |
Regioni | 239 – 377 | Coil 2Add BLAST | 139 | |
Regioni | 378 – 424 | TailAdd BLAST | 47 |
Sequence similaritiesi
Belongs to the intermediate filament family.PROSITE-ProRule annotation
Keywords - Domaini
Coiled coilPhylogenomic databases
eggNOGi | ENOG502QUY3, Eukaryota |
GeneTreei | ENSGT00940000161855 |
HOGENOMi | CLU_012560_8_1_1 |
InParanoidi | P35900 |
OMAi | YSAYYKQ |
OrthoDBi | 798081at2759 |
PhylomeDBi | P35900 |
TreeFami | TF332742 |
Family and domain databases
InterProi | View protein in InterPro IPR018039, IF_conserved IPR039008, IF_rod_dom IPR002957, Keratin_I |
PANTHERi | PTHR23239, PTHR23239, 1 hit |
Pfami | View protein in Pfam PF00038, Filament, 1 hit |
PRINTSi | PR01248, TYPE1KERATIN |
SMARTi | View protein in SMART SM01391, Filament, 1 hit |
PROSITEi | View protein in PROSITE PS00226, IF_ROD_1, 1 hit PS51842, IF_ROD_2, 1 hit |
i Sequence
Sequence statusi: Complete.
P35900-1 [UniParc]FASTAAdd to basket
10 20 30 40 50
MDFSRRSFHR SLSSSLQAPV VSTVGMQRLG TTPSVYGGAG GRGIRISNSR
60 70 80 90 100
HTVNYGSDLT GGGDLFVGNE KMAMQNLNDR LASYLEKVRT LEQSNSKLEV
110 120 130 140 150
QIKQWYETNA PRAGRDYSAY YRQIEELRSQ IKDAQLQNAR CVLQIDNAKL
160 170 180 190 200
AAEDFRLKYE TERGIRLTVE ADLQGLNKVF DDLTLHKTDL EIQIEELNKD
210 220 230 240 250
LALLKKEHQE EVDGLHKHLG NTVNVEVDAA PGLNLGVIMN EMRQKYEVMA
260 270 280 290 300
QKNLQEAKEQ FERQTAVLQQ QVTVNTEELK GTEVQLTELR RTSQSLEIEL
310 320 330 340 350
QSHLSMKESL EHTLEETKAR YSSQLANLQS LLSSLEAQLM QIRSNMERQN
360 370 380 390 400
NEYHILLDIK TRLEQEIATY RRLLEGEDVK TTEYQLSTLE ERDIKKTRKI
410 420
KTVVQEVVDG KVVSSEVKEV EENI
Experimental Info
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sequence conflicti | 161 | T → S in CAA51914 (PubMed:7689500).Curated | 1 | |
Sequence conflicti | 349 | Q → P in CAA51914 (PubMed:7689500).Curated | 1 | |
Sequence conflicti | 398 | R → T in CAA51914 (PubMed:7689500).Curated | 1 |
Natural variant
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Natural variantiVAR_036367 | 4 | S → R in a colorectal cancer sample; somatic mutation. 1 Publication | 1 | |
Natural variantiVAR_024489 | 129 | S → N1 PublicationCorresponds to variant dbSNP:rs7212483Ensembl. | 1 | |
Natural variantiVAR_064726 | 214 | G → C Found in a renal cell carcinoma sample; somatic mutation. 1 Publication | 1 |
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | X73501 Genomic DNA Translation: CAA51913.1 AK312744 mRNA Translation: BAG35614.1 BC031559 mRNA Translation: AAH31559.1 X73502 mRNA Translation: CAA51914.1 |
CCDSi | CCDS11379.1 |
PIRi | S37780 |
RefSeqi | NP_061883.1, NM_019010.2 |
Genome annotation databases
Ensembli | ENST00000167588.4; ENSP00000167588.3; ENSG00000171431.4 ENST00000576098.2; ENSP00000460501.2; ENSG00000263057.2 |
GeneIDi | 54474 |
KEGGi | hsa:54474 |
MANE-Selecti | ENST00000167588.4; ENSP00000167588.3; NM_019010.3; NP_061883.1 |
UCSCi | uc002hvl.4, human |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | X73501 Genomic DNA Translation: CAA51913.1 AK312744 mRNA Translation: BAG35614.1 BC031559 mRNA Translation: AAH31559.1 X73502 mRNA Translation: CAA51914.1 |
CCDSi | CCDS11379.1 |
PIRi | S37780 |
RefSeqi | NP_061883.1, NM_019010.2 |
3D structure databases
AlphaFoldDBi | P35900 |
SMRi | P35900 |
ModBasei | Search... |
Protein-protein interaction databases
BioGRIDi | 119979, 50 interactors |
IntActi | P35900, 47 interactors |
MINTi | P35900 |
STRINGi | 9606.ENSP00000167588 |
PTM databases
iPTMneti | P35900 |
PhosphoSitePlusi | P35900 |
SwissPalmi | P35900 |
Genetic variation databases
BioMutai | KRT20 |
DMDMi | 547750 |
Proteomic databases
jPOSTi | P35900 |
MassIVEi | P35900 |
PaxDbi | P35900 |
PeptideAtlasi | P35900 |
PRIDEi | P35900 |
ProteomicsDBi | 55160 |
Protocols and materials databases
Antibodypediai | 3502, 1326 antibodies from 50 providers |
DNASUi | 54474 |
Genome annotation databases
Ensembli | ENST00000167588.4; ENSP00000167588.3; ENSG00000171431.4 ENST00000576098.2; ENSP00000460501.2; ENSG00000263057.2 |
GeneIDi | 54474 |
KEGGi | hsa:54474 |
MANE-Selecti | ENST00000167588.4; ENSP00000167588.3; NM_019010.3; NP_061883.1 |
UCSCi | uc002hvl.4, human |
Organism-specific databases
CTDi | 54474 |
DisGeNETi | 54474 |
GeneCardsi | KRT20 |
HGNCi | HGNC:20412, KRT20 |
HPAi | ENSG00000171431, Tissue enriched (intestine) |
MIMi | 608218, gene |
neXtProti | NX_P35900 |
OpenTargetsi | ENSG00000171431 |
PharmGKBi | PA134938907 |
VEuPathDBi | HostDB:ENSG00000171431 |
GenAtlasi | Search... |
Phylogenomic databases
eggNOGi | ENOG502QUY3, Eukaryota |
GeneTreei | ENSGT00940000161855 |
HOGENOMi | CLU_012560_8_1_1 |
InParanoidi | P35900 |
OMAi | YSAYYKQ |
OrthoDBi | 798081at2759 |
PhylomeDBi | P35900 |
TreeFami | TF332742 |
Enzyme and pathway databases
PathwayCommonsi | P35900 |
Reactomei | R-HSA-6805567, Keratinization R-HSA-6809371, Formation of the cornified envelope |
SignaLinki | P35900 |
SIGNORi | P35900 |
Miscellaneous databases
BioGRID-ORCSi | 54474, 13 hits in 1068 CRISPR screens |
ChiTaRSi | KRT20, human |
GeneWikii | Keratin_20 |
GenomeRNAii | 54474 |
Pharosi | P35900, Tbio |
PROi | PR:P35900 |
RNActi | P35900, protein |
SOURCEi | Search... |
Gene expression databases
Bgeei | ENSG00000171431, Expressed in colon and 106 other tissues |
Genevisiblei | P35900, HS |
Family and domain databases
InterProi | View protein in InterPro IPR018039, IF_conserved IPR039008, IF_rod_dom IPR002957, Keratin_I |
PANTHERi | PTHR23239, PTHR23239, 1 hit |
Pfami | View protein in Pfam PF00038, Filament, 1 hit |
PRINTSi | PR01248, TYPE1KERATIN |
SMARTi | View protein in SMART SM01391, Filament, 1 hit |
PROSITEi | View protein in PROSITE PS00226, IF_ROD_1, 1 hit PS51842, IF_ROD_2, 1 hit |
MobiDBi | Search... |
Entry informationi
Entry namei | K1C20_HUMAN | |
Accessioni | P35900Primary (citable) accession number: P35900 Secondary accession number(s): B2R6W7 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | June 1, 1994 |
Last sequence update: | June 1, 1994 | |
Last modified: | May 25, 2022 | |
This is version 187 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Chordata Protein Annotation Program | |
Disclaimer | Any 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
Direct protein sequencing, Reference proteomeDocuments
- Human chromosome 17
Human chromosome 17: entries, gene names and cross-references to MIM - Human entries with genetic variants
List of human entries with genetic variants - Human variants curated from literature reports
Index of human variants curated from literature reports - MIM cross-references
Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot - SIMILARITY comments
Index of protein domains and families