ID   K1C20_MOUSE             Reviewed;         431 AA.
AC   Q9D312; Q6PG82;
DT   23-OCT-2007, integrated into UniProtKB/Swiss-Prot.
DT   01-JUN-2001, sequence version 1.
DT   27-MAR-2024, entry version 149.
DE   RecName: Full=Keratin, type I cytoskeletal 20;
DE   AltName: Full=Cytokeratin-20;
DE            Short=CK-20;
DE   AltName: Full=Keratin-20;
DE            Short=K20;
GN   Name=Krt20 {ECO:0000312|EMBL:AAH57172.1, ECO:0000312|MGI:MGI:1914059};
OS   Mus musculus (Mouse).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia;
OC   Eutheria; Euarchontoglires; Glires; Rodentia; Myomorpha; Muroidea; Muridae;
OC   Murinae; Mus; Mus.
OX   NCBI_TaxID=10090;
RN   [1] {ECO:0000305, ECO:0000312|EMBL:AAL82480.1}
RP   NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, INTERACTION WITH KRT8, AND TISSUE
RP   SPECIFICITY.
RX   PubMed=12857878; DOI=10.1091/mbc.e03-02-0059;
RA   Zhou Q., Toivola D.M., Feng N., Greenberg H.B., Franke W.W., Omary M.B.;
RT   "Keratin 20 helps maintain intermediate filament organization in intestinal
RT   epithelia.";
RL   Mol. Biol. Cell 14:2959-2971(2003).
RN   [2] {ECO:0000312|EMBL:BAB31280.1}
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC   STRAIN=C57BL/6J {ECO:0000312|EMBL:BAB31280.1};
RC   TISSUE=Colon {ECO:0000312|EMBL:BAB31280.1};
RX   PubMed=16141072; DOI=10.1126/science.1112014;
RA   Carninci P., Kasukawa T., Katayama S., Gough J., Frith M.C., Maeda N.,
RA   Oyama R., Ravasi T., Lenhard B., Wells C., Kodzius R., Shimokawa K.,
RA   Bajic V.B., Brenner S.E., Batalov S., Forrest A.R., Zavolan M., Davis M.J.,
RA   Wilming L.G., Aidinis V., Allen J.E., Ambesi-Impiombato A., Apweiler R.,
RA   Aturaliya R.N., Bailey T.L., Bansal M., Baxter L., Beisel K.W., Bersano T.,
RA   Bono H., Chalk A.M., Chiu K.P., Choudhary V., Christoffels A.,
RA   Clutterbuck D.R., Crowe M.L., Dalla E., Dalrymple B.P., de Bono B.,
RA   Della Gatta G., di Bernardo D., Down T., Engstrom P., Fagiolini M.,
RA   Faulkner G., Fletcher C.F., Fukushima T., Furuno M., Futaki S.,
RA   Gariboldi M., Georgii-Hemming P., Gingeras T.R., Gojobori T., Green R.E.,
RA   Gustincich S., Harbers M., Hayashi Y., Hensch T.K., Hirokawa N., Hill D.,
RA   Huminiecki L., Iacono M., Ikeo K., Iwama A., Ishikawa T., Jakt M.,
RA   Kanapin A., Katoh M., Kawasawa Y., Kelso J., Kitamura H., Kitano H.,
RA   Kollias G., Krishnan S.P., Kruger A., Kummerfeld S.K., Kurochkin I.V.,
RA   Lareau L.F., Lazarevic D., Lipovich L., Liu J., Liuni S., McWilliam S.,
RA   Madan Babu M., Madera M., Marchionni L., Matsuda H., Matsuzawa S., Miki H.,
RA   Mignone F., Miyake S., Morris K., Mottagui-Tabar S., Mulder N., Nakano N.,
RA   Nakauchi H., Ng P., Nilsson R., Nishiguchi S., Nishikawa S., Nori F.,
RA   Ohara O., Okazaki Y., Orlando V., Pang K.C., Pavan W.J., Pavesi G.,
RA   Pesole G., Petrovsky N., Piazza S., Reed J., Reid J.F., Ring B.Z.,
RA   Ringwald M., Rost B., Ruan Y., Salzberg S.L., Sandelin A., Schneider C.,
RA   Schoenbach C., Sekiguchi K., Semple C.A., Seno S., Sessa L., Sheng Y.,
RA   Shibata Y., Shimada H., Shimada K., Silva D., Sinclair B., Sperling S.,
RA   Stupka E., Sugiura K., Sultana R., Takenaka Y., Taki K., Tammoja K.,
RA   Tan S.L., Tang S., Taylor M.S., Tegner J., Teichmann S.A., Ueda H.R.,
RA   van Nimwegen E., Verardo R., Wei C.L., Yagi K., Yamanishi H.,
RA   Zabarovsky E., Zhu S., Zimmer A., Hide W., Bult C., Grimmond S.M.,
RA   Teasdale R.D., Liu E.T., Brusic V., Quackenbush J., Wahlestedt C.,
RA   Mattick J.S., Hume D.A., Kai C., Sasaki D., Tomaru Y., Fukuda S.,
RA   Kanamori-Katayama M., Suzuki M., Aoki J., Arakawa T., Iida J., Imamura K.,
RA   Itoh M., Kato T., Kawaji H., Kawagashira N., Kawashima T., Kojima M.,
RA   Kondo S., Konno H., Nakano K., Ninomiya N., Nishio T., Okada M., Plessy C.,
RA   Shibata K., Shiraki T., Suzuki S., Tagami M., Waki K., Watahiki A.,
RA   Okamura-Oho Y., Suzuki H., Kawai J., Hayashizaki Y.;
RT   "The transcriptional landscape of the mammalian genome.";
RL   Science 309:1559-1563(2005).
RN   [3]
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
RC   STRAIN=C57BL/6J;
RX   PubMed=19468303; DOI=10.1371/journal.pbio.1000112;
RA   Church D.M., Goodstadt L., Hillier L.W., Zody M.C., Goldstein S., She X.,
RA   Bult C.J., Agarwala R., Cherry J.L., DiCuccio M., Hlavina W., Kapustin Y.,
RA   Meric P., Maglott D., Birtle Z., Marques A.C., Graves T., Zhou S.,
RA   Teague B., Potamousis K., Churas C., Place M., Herschleb J., Runnheim R.,
RA   Forrest D., Amos-Landgraf J., Schwartz D.C., Cheng Z., Lindblad-Toh K.,
RA   Eichler E.E., Ponting C.P.;
RT   "Lineage-specific biology revealed by a finished genome assembly of the
RT   mouse.";
RL   PLoS Biol. 7:E1000112-E1000112(2009).
RN   [4] {ECO:0000312|EMBL:AAH57172.1}
RP   NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
RC   STRAIN=FVB/N {ECO:0000312|EMBL:AAH57172.1};
RC   TISSUE=Colon {ECO:0000312|EMBL:AAH57172.1};
RX   PubMed=15489334; DOI=10.1101/gr.2596504;
RG   The MGC Project Team;
RT   "The status, quality, and expansion of the NIH full-length cDNA project:
RT   the Mammalian Gene Collection (MGC).";
RL   Genome Res. 14:2121-2127(2004).
RN   [5] {ECO:0000312|EMBL:CAM21365.1}
RP   PROTEIN SEQUENCE OF 79-87 AND 370-378, AND IDENTIFICATION BY MASS
RP   SPECTROMETRY.
RC   STRAIN=OF1; TISSUE=Hippocampus;
RA   Lubec G., Sunyer B., Chen W.-Q.;
RL   Submitted (JAN-2009) to UniProtKB.
RN   [6] {ECO:0000305}
RP   FUNCTION, TISSUE SPECIFICITY, AND PHOSPHORYLATION AT SER-13.
RX   PubMed=16608857; DOI=10.1074/jbc.m512284200;
RA   Zhou Q., Cadrin M., Herrmann H., Chen C.-H., Chalkley R.J.,
RA   Burlingame A.L., Omary M.B.;
RT   "Keratin 20 serine 13 phosphorylation is a stress and intestinal goblet
RT   cell marker.";
RL   J. Biol. Chem. 281:16453-16461(2006).
RN   [7]
RP   IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
RC   TISSUE=Liver;
RX   PubMed=17242355; DOI=10.1073/pnas.0609836104;
RA   Villen J., Beausoleil S.A., Gerber S.A., Gygi S.P.;
RT   "Large-scale phosphorylation analysis of mouse liver.";
RL   Proc. Natl. Acad. Sci. U.S.A. 104:1488-1493(2007).
RN   [8]
RP   PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-16, AND IDENTIFICATION BY
RP   MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
RC   TISSUE=Kidney, and Pancreas;
RX   PubMed=21183079; DOI=10.1016/j.cell.2010.12.001;
RA   Huttlin E.L., Jedrychowski M.P., Elias J.E., Goswami T., Rad R.,
RA   Beausoleil S.A., Villen J., Haas W., Sowa M.E., Gygi S.P.;
RT   "A tissue-specific atlas of mouse protein phosphorylation and expression.";
RL   Cell 143:1174-1189(2010).
RN   [9]
RP   PHOSPHORYLATION AT SER-13 BY MAPKAPK2 AND MAPKAPK3.
RX   PubMed=20724476; DOI=10.1074/jbc.m110.132357;
RA   Menon M.B., Schwermann J., Singh A.K., Franz-Wachtel M., Pabst O.,
RA   Seidler U., Omary M.B., Kotlyarov A., Gaestel M.;
RT   "p38 MAP kinase and MAPKAP kinases MK2/3 cooperatively phosphorylate
RT   epithelial keratins.";
RL   J. Biol. Chem. 285:33242-33251(2010).
CC   -!- FUNCTION: Plays a significant role in maintaining keratin filament
CC       organization in intestinal epithelia. When phosphorylated, plays a role
CC       in the secretion of mucin in the small intestine.
CC       {ECO:0000269|PubMed:12857878, ECO:0000269|PubMed:16608857}.
CC   -!- SUBUNIT: Heterotetramer of two type I and two type II keratins.
CC       Associates with KRT8. {ECO:0000269|PubMed:12857878, ECO:0000305}.
CC   -!- TISSUE SPECIFICITY: Expressed at low levels in the more differentiated
CC       suprabasal regions of the small intestine, and at higher levels in the
CC       colon, mainly in the upper region and in scattered cells throughout the
CC       remaining epithelium. Also expressed in epithelial cells of bladder,
CC       ileum and stomach and at lower levels in pancreas and earskin. The
CC       phosphorylated form is nearly exclusively expressed in goblet cells of
CC       the small intestine and in the lumen-proximal cells of the colon (at
CC       protein level). Also expressed in jejunum and duodenum.
CC       {ECO:0000269|PubMed:12857878, ECO:0000269|PubMed:16608857}.
CC   -!- PTM: Hyperphosphorylation at Ser-13 occurs during the early stages of
CC       apoptosis but becomes less prominent during the later stages (By
CC       similarity). Phosphorylation at Ser-13 also increases in response to
CC       stress brought on by cell injury. {ECO:0000250|UniProtKB:P35900,
CC       ECO:0000269|PubMed:16608857, ECO:0000269|PubMed:20724476}.
CC   -!- PTM: Proteolytically cleaved by caspases during apoptosis. Cleavage
CC       occurs at Asp-235 (By similarity). {ECO:0000250|UniProtKB:P35900}.
CC   -!- MISCELLANEOUS: There are two types of cytoskeletal and microfibrillar
CC       keratin: I (acidic; 40-55 kDa) and II (neutral to basic; 56-70 kDa).
CC       {ECO:0000305}.
CC   -!- SIMILARITY: Belongs to the intermediate filament family.
CC       {ECO:0000255|PROSITE-ProRule:PRU01188}.
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DR   EMBL; AF473907; AAL82480.1; -; mRNA.
DR   EMBL; AK018567; BAB31280.1; -; mRNA.
DR   EMBL; AL591165; CAM21365.1; -; Genomic_DNA.
DR   EMBL; BC057172; AAH57172.1; -; mRNA.
DR   CCDS; CCDS25381.1; -.
DR   RefSeq; NP_075745.1; NM_023256.2.
DR   AlphaFoldDB; Q9D312; -.
DR   SMR; Q9D312; -.
DR   BioGRID; 211731; 1.
DR   STRING; 10090.ENSMUSP00000017743; -.
DR   iPTMnet; Q9D312; -.
DR   PhosphoSitePlus; Q9D312; -.
DR   PaxDb; 10090-ENSMUSP00000017743; -.
DR   PeptideAtlas; Q9D312; -.
DR   ProteomicsDB; 269050; -.
DR   Antibodypedia; 3502; 1603 antibodies from 50 providers.
DR   DNASU; 66809; -.
DR   Ensembl; ENSMUST00000017743.3; ENSMUSP00000017743.3; ENSMUSG00000035775.3.
DR   GeneID; 66809; -.
DR   KEGG; mmu:66809; -.
DR   UCSC; uc007liu.1; mouse.
DR   AGR; MGI:1914059; -.
DR   CTD; 54474; -.
DR   MGI; MGI:1914059; Krt20.
DR   VEuPathDB; HostDB:ENSMUSG00000035775; -.
DR   eggNOG; ENOG502QUY3; Eukaryota.
DR   GeneTree; ENSGT00940000161855; -.
DR   HOGENOM; CLU_012560_8_1_1; -.
DR   InParanoid; Q9D312; -.
DR   OMA; LGTIMNE; -.
DR   OrthoDB; 4640531at2759; -.
DR   PhylomeDB; Q9D312; -.
DR   TreeFam; TF332742; -.
DR   Reactome; R-MMU-6805567; Keratinization.
DR   Reactome; R-MMU-6809371; Formation of the cornified envelope.
DR   BioGRID-ORCS; 66809; 4 hits in 78 CRISPR screens.
DR   ChiTaRS; Krt20; mouse.
DR   PRO; PR:Q9D312; -.
DR   Proteomes; UP000000589; Chromosome 11.
DR   RNAct; Q9D312; Protein.
DR   Bgee; ENSMUSG00000035775; Expressed in small intestine Peyer's patch and 87 other cell types or tissues.
DR   GO; GO:0005737; C:cytoplasm; ISO:MGI.
DR   GO; GO:0005856; C:cytoskeleton; IBA:GO_Central.
DR   GO; GO:0005829; C:cytosol; ISO:MGI.
DR   GO; GO:0005882; C:intermediate filament; IEA:UniProtKB-KW.
DR   GO; GO:0045111; C:intermediate filament cytoskeleton; ISO:MGI.
DR   GO; GO:0005198; F:structural molecule activity; IEA:InterPro.
DR   GO; GO:0006915; P:apoptotic process; IEA:UniProtKB-KW.
DR   GO; GO:0009267; P:cellular response to starvation; IDA:UniProtKB.
DR   GO; GO:0030855; P:epithelial cell differentiation; IBA:GO_Central.
DR   GO; GO:0045109; P:intermediate filament organization; IMP:UniProtKB.
DR   GO; GO:0050708; P:regulation of protein secretion; IDA:UniProtKB.
DR   Gene3D; 1.20.5.170; -; 1.
DR   Gene3D; 1.20.5.500; Single helix bin; 1.
DR   Gene3D; 1.20.5.1160; Vasodilator-stimulated phosphoprotein; 1.
DR   InterPro; IPR018039; IF_conserved.
DR   InterPro; IPR039008; IF_rod_dom.
DR   InterPro; IPR002957; Keratin_I.
DR   PANTHER; PTHR23239; INTERMEDIATE FILAMENT; 1.
DR   PANTHER; PTHR23239:SF167; KERATIN, TYPE I CYTOSKELETAL 20; 1.
DR   Pfam; PF00038; Filament; 1.
DR   PRINTS; PR01248; TYPE1KERATIN.
DR   SMART; SM01391; Filament; 1.
DR   SUPFAM; SSF64593; Intermediate filament protein, coiled coil region; 2.
DR   PROSITE; PS00226; IF_ROD_1; 1.
DR   PROSITE; PS51842; IF_ROD_2; 1.
DR   Genevisible; Q9D312; MM.
PE   1: Evidence at protein level;
KW   Apoptosis; Coiled coil; Direct protein sequencing; Intermediate filament;
KW   Keratin; Phosphoprotein; Reference proteome.
FT   CHAIN           1..431
FT                   /note="Keratin, type I cytoskeletal 20"
FT                   /id="PRO_0000308358"
FT   DOMAIN          77..388
FT                   /note="IF rod"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU01188"
FT   REGION          1..76
FT                   /note="Head"
FT                   /evidence="ECO:0000255"
FT   REGION          1..23
FT                   /note="Disordered"
FT                   /evidence="ECO:0000256|SAM:MobiDB-lite"
FT   REGION          77..112
FT                   /note="Coil 1A"
FT                   /evidence="ECO:0000255"
FT   REGION          113..130
FT                   /note="Linker 1"
FT                   /evidence="ECO:0000255"
FT   REGION          131..222
FT                   /note="Coil 1B"
FT                   /evidence="ECO:0000255"
FT   REGION          223..245
FT                   /note="Linker 12"
FT                   /evidence="ECO:0000255"
FT   REGION          246..384
FT                   /note="Coil 2"
FT                   /evidence="ECO:0000255"
FT   REGION          385..431
FT                   /note="Tail"
FT                   /evidence="ECO:0000255"
FT   SITE            235..236
FT                   /note="Cleavage; by caspases"
FT                   /evidence="ECO:0000250"
FT   MOD_RES         13
FT                   /note="Phosphoserine; by MAPKAPK2, MAPKAPK3 and PKC"
FT                   /evidence="ECO:0000269|PubMed:16608857,
FT                   ECO:0000269|PubMed:20724476"
FT   MOD_RES         16
FT                   /note="Phosphoserine"
FT                   /evidence="ECO:0007744|PubMed:21183079"
FT   MOD_RES         26
FT                   /note="Phosphoserine"
FT                   /evidence="ECO:0000250|UniProtKB:P25030"
FT   CONFLICT        24
FT                   /note="S -> N (in Ref. 4; AAH57172)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        151
FT                   /note="R -> Q (in Ref. 4; AAH57172)"
FT                   /evidence="ECO:0000305"
FT   CONFLICT        173
FT                   /note="R -> H (in Ref. 4; AAH57172)"
FT                   /evidence="ECO:0000305"
SQ   SEQUENCE   431 AA;  49034 MW;  5375E42A8BA0ACB3 CRC64;
     MDFSRQSFHR SLSSSSQGPA LSMSGSLYRK GTVQRLGAAP SVYGGAGGHG TRISVSKAVM
     SYGGDLSNGS DLFGGNGKLA MQNLNDRLAN YLEKVRSLEQ SNSRLEAQIK QWYETNAPST
     IRDYSSYYAQ IKELQNQVKD AQVQNAQCVL RIDNAKLAAE DFRLKFETER GMRIAVEADL
     QGLSKVYDNL TLQKTDLEIQ IEELNKDLAL LKKEHQEEVE VLRRQLGNNV NVEVDAAPGL
     NLGEIMNEMR QRYEVLAQKN LQEAKEQFER QSQTLQQQVT VNTEELKGFE VQVTELRRTY
     QNLEIELQSH LSMKESLERN LEDVKARYAS QLAAIQEMLS SLEAQLMQIR SDTERQNQEH
     NILLDIKTRL EQEIATYRRL LEGEDIKTTE YQLSTLEMKD IKKTRKIKTV VEEVVDGKVV
     SSEVKEIEES V
//