<p>Provides any useful information about the protein, mostly biological knowledge.</p><p><a href='../manual/function_section' target='_top'>More...</a></p>Functionⁱ

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:</p><p><a href='../manual/gene_ontology' target='_top'>More...</a></p>GO - Molecular functionⁱ

1. cyclin-dependent protein serine/threonine kinase inhibitor activity Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 8001816

2. protein kinase binding Source: BHF-UCL

   <p>Inferred from Physical Interaction</p> <p>Covers physical interactions between the gene product of interest and another molecule (or ion, or complex).</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ipi">GO evidence code guide</a></p> Inferred from physical interactionⁱ

   • 8001816

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:</p><p><a href='../manual/gene_ontology' target='_top'>More...</a></p>GO - Biological processⁱ

1. cell cycle arrest Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 10208428

2. G1/S transition of mitotic cell cycle Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 10208428

3. mitotic cell cycle Source: Reactome
4. negative regulation of cell growth Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 10208428

5. negative regulation of cell proliferation Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 10208428

6. negative regulation of phosphorylation Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 10208428

7. negative regulation of protein serine/threonine kinase activity Source: GOC

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 8001816

8. oligodendrocyte differentiation Source: Ensembl
9. regulation of cyclin-dependent protein serine/threonine kinase activity Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 8001816

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Biological processⁱ

Enzyme and pathway databases

<p>Provides information about the protein and gene name(s) and synonym(s) and about the organism that is the source of the protein sequence.</p><p><a href='../manual/names_and_taxonomy_section' target='_top'>More...</a></p>Names & Taxonomyⁱ

Organism-specific databases

<p>Provides information on the location and the topology of the mature protein in the cell.</p><p><a href='../manual/subcellular_location_section' target='_top'>More...</a></p>Subcellular locationⁱ

<p>The <a href="http://www.geneontology.org/">Gene Ontology (GO)</a> project provides a set of hierarchical controlled vocabulary split into 3 categories:</p><p><a href='../manual/gene_ontology' target='_top'>More...</a></p>GO - Cellular componentⁱ

1. cytoplasm Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 11800646

2. cytosol Source: Reactome
3. nucleus Source: BHF-UCL

   <p>Inferred from Direct Assay</p> <p>Used to indicate a direct assay for the function, process or component indicated by the GO term.</p> <p>More information in the <a href="http://geneontology.org/page/guide-go-evidence-codes#ida">GO evidence code guide</a></p> Inferred from direct assayⁱ

   • 11800646

<p>Provides information on the disease(s) and phenotype(s) associated with the deficiency of a protein.</p><p><a href='../manual/pathology_and_biotech_section' target='_top'>More...</a></p>Pathology & Biotechⁱ

Organism-specific databases

<p>Describes post-translational modifications (PTMs) and/or processing events.</p><p><a href='../manual/ptm_processing_section' target='_top'>More...</a></p>PTM / Processingⁱ

Molecule processing

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Describes the extent of a polypeptide chain in the mature protein following processing.</p><p><a href='../manual/chain' target='_top'>More...</a></p>Chaini	1 – 168	168	Cyclin-dependent kinase 4 inhibitor C		PRO_0000144186	Add BLAST

Proteomic databases

PTM databases

<p>Provides information on the expression of a gene at the mRNA or protein level in cells or in tissues of multicellular organisms.</p><p><a href='../manual/expression_section' target='_top'>More...</a></p>Expressionⁱ

<p>Provides information on the expression of a gene at the mRNA or protein level in cells or in tissues of multicellular organisms. By default, the information is derived from experiments at the mRNA level, unless specified ‘at the protein level’.</p><p><a href='../manual/tissue_specificity' target='_top'>More...</a></p>Tissue specificityⁱ

Gene expression databases

Organism-specific databases

<p>Provides information on the quaternary structure of a protein and on interaction(s) with other proteins or protein complexes.</p><p><a href='../manual/interaction_section' target='_top'>More...</a></p>Interactionⁱ

<p>Provides information about the protein quaternary structure and interaction(s) with other proteins or protein complexes (with the exception of physiological receptor-ligand interactions which are annotated in the ‘Function’ section).</p><p><a href='../manual/subunit_structure' target='_top'>More...</a></p>Subunit structureⁱ

<p>Provides information about binary protein-protein interactions. The data presented in this section are a quality-filtered subset of binary interactions automatically derived from the <a href="http://www.ebi.ac.uk/intact/">IntAct database</a>. It is updated on a monthly basis. Each binary interaction is displayed on a separate line.</p><p><a href='../manual/binary_interactions' target='_top'>More...</a></p>Binary interactionsⁱ

Protein-protein interaction databases

<p>Provides information on the tertiary structure of a protein.</p><p><a href='../manual/structure_section' target='_top'>More...</a></p>Structureⁱ

Secondary structure

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	6 – 15	10	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	18 – 24	7	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined hydrogen-bonded turns within the protein sequence. These elements correspond to the <span class="caps">DSSP</span> secondary structure code ‘T’.</p><p><a href='../manual/turn' target='_top'>More...</a></p>Turni	36 – 38	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1BU9
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	41 – 44	4	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined hydrogen-bonded turns within the protein sequence. These elements correspond to the <span class="caps">DSSP</span> secondary structure code ‘T’.</p><p><a href='../manual/turn' target='_top'>More...</a></p>Turni	45 – 48	4	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1BU9
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	50 – 58	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	73 – 80	8	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	83 – 91	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	101 – 103	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1BU9
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	106 – 112	7	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	116 – 125	10	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined beta strands within the protein sequence.</p><p><a href='../manual/strand' target='_top'>More...</a></p>Beta strandi	135 – 137	3	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1BU9
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	140 – 146	7	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB
<p>Is used to indicate the positions of experimentally determined helical regions within the protein sequence.</p><p><a href='../manual/helix' target='_top'>More...</a></p>Helixi	150 – 158	9	Combined sources <p>Manually validated information inferred from a combination of experimental and computational evidence.</p> <p><a href="/manual/evidences#ECO:0000244">More…</a></p> Manual assertion inferred from combination of experimental and computational evidencei PDB:1IHB

3D structure databases

Miscellaneous databases

<p>Provides information on sequence similarities with other proteins and the domain(s) present in a protein.</p><p><a href='../manual/family_and_domains_section' target='_top'>More...</a></p>Family & Domainsⁱ

Domains and Repeats

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Indicates the positions and types of repeated sequence motifs or repeated domains within the protein.</p><p><a href='../manual/repeat' target='_top'>More...</a></p>Repeati	4 – 33	30	ANK 1			Add BLAST
<p>Indicates the positions and types of repeated sequence motifs or repeated domains within the protein.</p><p><a href='../manual/repeat' target='_top'>More...</a></p>Repeati	37 – 65	29	ANK 2			Add BLAST
<p>Indicates the positions and types of repeated sequence motifs or repeated domains within the protein.</p><p><a href='../manual/repeat' target='_top'>More...</a></p>Repeati	69 – 98	30	ANK 3			Add BLAST
<p>Indicates the positions and types of repeated sequence motifs or repeated domains within the protein.</p><p><a href='../manual/repeat' target='_top'>More...</a></p>Repeati	102 – 132	31	ANK 4			Add BLAST

<p>Provides information about the sequence similarity with other proteins.</p><p><a href='../manual/sequence_similarities' target='_top'>More...</a></p>Sequence similaritiesⁱ

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Domainⁱ

Phylogenomic databases

Family and domain databases

<p>Displays by default the canonical protein sequence and upon request all isoforms described in the entry. It also includes information pertinent to the sequence(s), including length and molecular weight.</p><p><a href='../manual/sequences_section' target='_top'>More...</a></p>Sequenceⁱ

<p>Indicates if the canonical sequence displayed by default in the entry is complete or not.</p><p><a href='../manual/sequence_status' target='_top'>More...</a></p>Sequence statusⁱ: Complete.

        10         20         30         40         50
MAEPWGNELA SAAARGDLEQ LTSLLQNNVN VNAQNGFGRT ALQVMKLGNP 
        60         70         80         90        100
EIARRLLLRG ANPDLKDRTG FAVIHDAARA GFLDTLQTLL EFQADVNIED 
       110        120        130        140        150
NEGNLPLHLA AKEGHLRVVE FLVKHTASNV GHRNHKGDTA CDLARLYGRN 
       160 
EVVSLMQANG AGGATNLQ                                  

Natural variant

Feature key	Position(s)	Length	Description	Graphical view	Feature identifier	Actions
<p>Describes natural variant(s) of the protein sequence.</p><p><a href='../manual/variant' target='_top'>More...</a></p>Natural varianti	72 – 72	1	A → P in breast cancer; loss of CDK6 interaction. 2 Publications <p>Manually curated information for which there is published experimental evidence.</p> <p><a href="/manual/evidences#ECO:0000269">More…</a></p> Manual assertion based on experiment ini Ref.2 "Structure of the gene encoding the human cyclin-dependent kinase inhibitor p18 and mutational analysis in breast cancer." Blais A., Labrie Y., Pouliot F., Lachance Y., Labrie C. Biochem. Biophys. Res. Commun. 247:146-153(1998) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], VARIANT BREAST CANCER PRO-72. Ref.8 "A p18 mutant defective in CDK6 binding in human breast cancer cells." Lapointe J., Lachance Y., Labrie Y., Labrie C. Cancer Res. 56:4586-4589(1996) [PubMed] [Europe PMC] [Abstract] Cited for: VARIANT BREAST CANCER PRO-72.		VAR_001490
<p>Describes natural variant(s) of the protein sequence.</p><p><a href='../manual/variant' target='_top'>More...</a></p>Natural varianti	126 – 126	1	T → M.1 Publication <p>Manually curated information for which there is published experimental evidence.</p> <p><a href="/manual/evidences#ECO:0000269">More…</a></p> Manual assertion based on experiment ini Ref.4 "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA], VARIANT MET-126. Corresponds to variant rs17851380 [ dbSNP | Ensembl ].		VAR_038604

Sequence databases

Genome annotation databases

Polymorphism databases

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Coding sequence diversityⁱ

<p>Is used to point to information related to entries and found in data collections other than UniProtKB.</p><p><a href='../manual/cross_references_section' target='_top'>More...</a></p>Cross-referencesⁱ

<p>Provides links to various web resources that are relevant for a specific protein.</p><p><a href='../manual/web_resource' target='_top'>More...</a></p>Web resourcesⁱ

Sequence databases

3D structure databases

Protein-protein interaction databases

PTM databases

Polymorphism databases

Proteomic databases

Protocols and materials databases

Genome annotation databases

Organism-specific databases

Phylogenomic databases

Enzyme and pathway databases

Miscellaneous databases

Gene expression databases

Family and domain databases

<p>Contains the literature citations that are the sources of data used to annotate the entry. Each reference is numbered and contains several subsections allowing a precise description of a given citation.</p><p><a href='../manual/publications_section' target='_top'>More...</a></p>Publicationsⁱ

1. "Growth suppression by p18, a p16INK4/MTS1- and p14INK4B/MTS2-related CDK6 inhibitor, correlates with wild-type pRb function."
   Guan K.-L., Jenkins C.W., Li Y., Nichols M.A., Wu X., O'Keefe C.L., Matera G.A., Xiong Y.
   Genes Dev. 8:2939-2952(1994) [PubMed] [Europe PMC] [Abstract]
   Cited for: NUCLEOTIDE SEQUENCE [MRNA].
2. "Structure of the gene encoding the human cyclin-dependent kinase inhibitor p18 and mutational analysis in breast cancer."
   Blais A., Labrie Y., Pouliot F., Lachance Y., Labrie C.
   Biochem. Biophys. Res. Commun. 247:146-153(1998) [PubMed] [Europe PMC] [Abstract]
   Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], VARIANT BREAST CANCER PRO-72.
   Tissue: Mammary gland.
   
3. NIEHS SNPs program
   Submitted (APR-2002) to the EMBL/GenBank/DDBJ databases
   Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA].
4. "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
   The MGC Project Team
   Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
   Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA], VARIANT MET-126.
   Tissue: Brain, Kidney and Uterus.
   
5. "Initial characterization of the human central proteome."
   Burkard T.R., Planyavsky M., Kaupe I., Breitwieser F.P., Buerckstuemmer T., Bennett K.L., Superti-Furga G., Colinge J.
   BMC Syst. Biol. 5:17-17(2011) [PubMed] [Europe PMC] [Abstract]
   Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
6. "Crystal structure of the CDK4/6 inhibitory protein p18INK4c provides insights into ankyrin-like repeat structure/function and tumor-derived p16INK4 mutations."
   Venkataramani R., Swaminathan K., Marmorstein R.
   Nat. Struct. Biol. 5:74-81(1998) [PubMed] [Europe PMC] [Abstract]
   Cited for: X-RAY CRYSTALLOGRAPHY (1.95 ANGSTROMS).
7. "Tumor suppressor INK4: determination of the solution structure of p18INK4C and demonstration of the functional significance of loops in p18INK4C and p16INK4A."
   Li J., Byeon I.-J.L., Ericson K., Poi M.-J., O'Maille P., Selby T., Tsai M.-D.
   Biochemistry 38:2930-2940(1999) [PubMed] [Europe PMC] [Abstract]
   Cited for: STRUCTURE BY NMR.
8. "A p18 mutant defective in CDK6 binding in human breast cancer cells."
   Lapointe J., Lachance Y., Labrie Y., Labrie C.
   Cancer Res. 56:4586-4589(1996) [PubMed] [Europe PMC] [Abstract]
   Cited for: VARIANT BREAST CANCER PRO-72.

<p>Provides general information on the entry.</p><p><a href='../manual/entry_information_section' target='_top'>More...</a></p>Entry informationⁱ

<p>Contains any relevant information that doesn’t fit in any other defined sections</p><p><a href='../manual/miscellaneous_section' target='_top'>More...</a></p>Miscellaneousⁱ

<p>UniProtKB Keywords constitute a <a target="_top" href="/keywords">controlled vocabulary</a> with a hierarchical structure. Keywords summarise the content of a UniProtKB entry and facilitate the search for proteins of interest.<p><a href='../help/keywords' target='_top'>More...</a></p>Keywords - Technical termⁱ

Documents

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

External Data

<p>Provides links to the UniProt Reference Clusters (<a href="/help/uniref">UniRef</a>). UniRef consists of clusters for UniProtKB sequences (including isoforms) and selected UniParc sequences, in order to obtain complete coverage of the sequence space at resolutions of 100%, 90% and 50% identity.</p><p><a href='../manual/similar_proteins_section' target='_top'>More...</a></p>Similar proteinsⁱ