Summary: Cyclin-dependent kinase inhibitor 2a p19Arf N-terminus
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P16 (gene) Edit Wikipedia article
||It has been suggested that Protein_P16 be merged into this article or section. (Discuss) Proposed since July 2012.|
|Cyclin-dependent kinase inhibitor 2A|
PDB rendering based on 1a5e.
|RNA expression pattern|
|Cyclin-dependent kinase inhibitor 2a p19Arf N-terminus|
|solution structure of the n-terminal 37 amino acids of the mouse arf tumor suppressor protein|
Cyclin-dependent kinase inhibitor 2A, (CDKN2A, p16Ink4A) also known as multiple tumor suppressor 1 (MTS-1), is a tumor suppressor protein, that in humans is encoded by the CDKN2A gene. P16 plays an important role in regulating the cell cycle, and mutations in p16 increase the risk of developing a variety of cancers, notably melanoma.
This gene generates several transcript variants that differ in their first exons. At least three alternatively spliced variants encoding distinct proteins have been reported, two of which encode structurally related isoforms known to function as inhibitors of CDK4. The remaining transcript includes an alternate exon 1 located 20 kb upstream of the remainder of the gene; this transcript contains an alternate open reading frame (ARF) that specifies a protein that is structurally unrelated to the products of the other variants. The ARF product functions as a stabilizer of the tumor suppressor protein p53, as it can interact with and sequester MDM2, a protein responsible for the degradation of p53. In spite of their structural and functional differences, the CDK inhibitor isoforms and the ARF product encoded by this gene, through the regulatory roles of CDK4 and p53 in cell cycle G1 progression, share a common functionality in control of the G1 phase of the cell cycle. This gene is frequently mutated or deleted in a wide variety of tumors and is known to be an important tumor suppressor gene.
Increased expression of the p16 gene as organisms age reduces the proliferation of stem cells. This reduction in the division and production of stem cells protects against cancer while increasing the risks associated with cellular senescence.
 Clinical significance
Concentrations of p16INK4a increase dramatically as tissue ages. Therefore p16INK4a could potentially be used as a blood test that measures how fast the body's tissues are aging at a molecular level.
P16 (gene) has been shown to interact with SERTAD1, CCNG1, Death associated protein 6, P53, E4F1, Cyclin-dependent kinase 4, Cyclin-dependent kinase 6, Mdm2, RPL11 and PPP1R9B.
- "Entrez Gene: CDKN2A cyclin-dependent kinase inhibitor 2A (melanoma, p16, inhibits CDK4)". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=1029.
- Nobori T, Miura K, Wu DJ, Lois A, Takabayashi K, Carson DA (April 1994). "Deletions of the cyclin-dependent kinase-4 inhibitor gene in multiple human cancers". Nature 368 (6473): 753â6. doi:10.1038/368753a0. PMID 8152487.
- Stone S, Jiang P, Dayananth P, Tavtigian SV, Katcher H, Parry D, Peters G, Kamb A (July 1995). "Complex structure and regulation of the P16 (MTS1) locus". Cancer Res. 55 (14): 2988â94. PMID 7606716. http://cancerres.aacrjournals.org/cgi/content/abstract/55/14/2988.
- "Molecular biology of cancer", Oxford University Press, 2005, ISBN 978-0-19-926472-8, Section 5.3
- Krishnamurthy J, Ramsey MR, Ligon KL, Torrice C, Koh A, Bonner-Weir S, Sharpless NE (September 2006). "p16INK4a induces an age-dependent decline in islet regenerative potential". Nature 443 (7110): 453â7. doi:10.1038/nature05092. PMID 16957737.
- Liggett WH, Sidransky D (March 1998). "Role of the p16 tumor suppressor gene in cancer". J. Clin. Oncol. 16 (3): 1197â206. PMID 9508208. http://www.jco.org/cgi/pmidlookup?view=long&pmid=9508208.
- Rocco JW, Sidransky D (March 2001). "p16(MTS-1/CDKN2/INK4a) in cancer progression". Exp. Cell Res. 264 (1): 42â55. doi:10.1006/excr.2000.5149. PMID 11237522.
- Caldas C, Hahn SA, da Costa LT, Redston MS, Schutte M, Seymour AB, Weinstein CL, Hruban RH et al. (September 1994). "Frequent somatic mutations and homozygous deletions of the p16 (MTS1) gene in pancreatic adenocarcinoma". Nat. Genet. 8 (1): 27â32. doi:10.1038/ng0994-27. PMID 7726912.
- Bartsch D, Shevlin DW, Tung WS, Kisker O, Wells SA, Goodfellow PJ (November 1995). "Frequent mutations of CDKN2 in primary pancreatic adenocarcinomas". Genes Chromosomes Cancer 14 (3): 189â95. doi:10.1002/gcc.2870140306. PMID 8589035.
- Liu L, Lassam NJ, Slingerland JM, Bailey D, Cole D, Jenkins R, Hogg D (July 1995). "Germline p16INK4A mutation and protein dysfunction in a family with inherited melanoma". Oncogene 11 (2): 405â12. PMID 7624155.
- Igaki H, Sasaki H, Kishi T, Sakamoto H, Tachimori Y, Kato H, Watanabe H, Sugimura T et al. (September 1994). "Highly frequent homozygous deletion of the p16 gene in esophageal cancer cell lines". Biochem. Biophys. Res. Commun. 203 (2): 1090â5. doi:10.1006/bbrc.1994.2294. PMID 8093026.
- Liu Y, Sanoff HK, Cho H, Burd CE, Torrice C, Ibrahim JG, Thomas NE, Sharpless NE (May 2009). "Expression of p16INK4a in peripheral blood T-cells is a biomarker of human aging". Aging Cell 8 (4): 439â48. doi:10.1111/j.1474-9726.2009.00489.x. PMC 2752333. PMID 19485966. //www.ncbi.nlm.nih.gov/pmc/articles/PMC2752333/. [BBC News Lay summary] â Hope for test to measure ageing.
- Li, Junan, , Tsai Ming-Daw, Muscarella Peter, Tsai, Ming-Daw, Muscarella, Peter (Apr. 2004). "The nuclear protein p34SEI-1 regulates the kinase activity of cyclin-dependent kinase 4 in a concentration-dependent manner". Biochemistry (United States) 43 (14): 4394â9. doi:10.1021/bi035601s. ISSN 0006-2960. PMID 15065884.
- Sugimoto, M, Ohtani N, Hampson L, Hampson I N, Shimamoto A, Furuichi Y, Okumura K, Niwa S et al. (Nov. 1999). "Regulation of CDK4 activity by a novel CDK4-binding protein, p34SEI-1". Genes Dev. (UNITED STATES) 13 (22): 3027â33. doi:10.1101/gad.13.22.3027. ISSN 0890-9369. PMC 317153. PMID 10580009. //www.ncbi.nlm.nih.gov/pmc/articles/PMC317153/.
- Zhao, Lili, Winckler Sarah, Korgaonkar Chandrashekhar, Tompkins Van, Horne Mary C, , Quelle Dawn E, Quelle, DE (Jan. 2003). "Cyclin G1 has growth inhibitory activity linked to the ARF-Mdm2-p53 and pRb tumor suppressor pathways". Mol. Cancer Res. (United States) 1 (3): 195â206. ISSN 1541-7786. PMID 12556559.
- Ivanchuk, Stacey M, , Rutka James T, Rutka, James T. (Jun. 2008). "p14ARF interacts with DAXX: effects on HDM2 and p53". Cell Cycle (United States) 7 (12): 1836â50. doi:10.4161/cc.7.12.6025. PMID 18583933.
- Zhang, Yanping, Bhat Krishna, Jin Aiwen, Allio Theresa, Burkhart William A, , Xiong Yue, Xiong, Y. (Dec. 2003). "Ribosomal Protein L11 Negatively Regulates Oncoprotein MDM2 and Mediates a p53-Dependent Ribosomal-Stress Checkpoint Pathway". Mol. Cell. Biol. (United States) 23 (23): 8902â12. doi:10.1128/MCB.23.23.8902-8912.2003. ISSN 0270-7306. PMC 262682. PMID 14612427. //www.ncbi.nlm.nih.gov/pmc/articles/PMC262682/.
- Rizos, Helen, Badhwar Prerna, Woodruff Sarah, Becker Therese M, Rooney Robert J, , Kefford Richard F, Kefford, RF (Feb. 2003). "Association of p14ARF with the p120E4F transcriptional repressor enhances cell cycle inhibition". J. Biol. Chem. (United States) 278 (7): 4981â9. doi:10.1074/jbc.M210978200. ISSN 0021-9258. PMID 12446718.
- Zhang, Y, , Yarbrough W G, Yarbrough, Wendell G (Mar. 1998). "ARF promotes MDM2 degradation and stabilizes p53: ARF-INK4a locus deletion impairs both the Rb and p53 tumor suppression pathways". Cell (UNITED STATES) 92 (6): 725â34. doi:10.1016/S0092-8674(00)81401-4. ISSN 0092-8674. PMID 9529249.
- Ewing, Rob M, Elisma Fred, Li Hongyan, Taylor Paul, Climie Shane, McBroom-Cerajewski Linda, Robinson Mark D, Connor Liam et al. (2007). "Large-scale mapping of human proteinâprotein interactions by mass spectrometry". Mol. Syst. Biol. (England) 3 (1): 89. doi:10.1038/msb4100134. PMC 1847948. PMID 17353931. //www.ncbi.nlm.nih.gov/pmc/articles/PMC1847948/.
- FÃ¥hraeus, R, Ball K L, LaÃn S, , Lane D P, Lane, David P. (Jan. 1996). "Inhibition of pRb phosphorylation and cell-cycle progression by a 20-residue peptide derived from p16CDKN2/INK4A". Curr. Biol. (ENGLAND) 6 (1): 84â91. doi:10.1016/S0960-9822(02)00425-6. ISSN 0960-9822. PMID 8805225.
- Serrano, M, , Beach D, Beach, David (Dec. 1993). "A new regulatory motif in cell-cycle control causing specific inhibition of cyclin D/CDK4". Nature (ENGLAND) 366 (6456): 704â7. doi:10.1038/366704a0. ISSN 0028-0836. PMID 8259215.
- Coleman, K G, Morrissey D, Mulheron J, Sedman S A, Brinkley P, Price S, , Webster K R, Webster, KR (Jul. 1997). "Identification of CDK4 sequences involved in cyclin D1 and p16 binding". J. Biol. Chem. (UNITED STATES) 272 (30): 18869â74. doi:10.1074/jbc.272.30.18869. ISSN 0021-9258. PMID 9228064.
- Russo, A A, Lee J O, Jeffrey P D, , Pavletich N P, Jeffrey, Philip D. (Sep. 1998). "Structural basis for inhibition of the cyclin-dependent kinase Cdk6 by the tumour suppressor p16INK4a". Nature (ENGLAND) 395 (6699): 237â43. doi:10.1038/26155. ISSN 0028-0836. PMID 9751050.
- Kaldis, P, Tong L, MÃ¤kelÃ¤ T P, , Solomon M J, Solomon, MJ (Dec. 2001). "CAK-independent Activation of CDK6 by a Viral Cyclin". Mol. Biol. Cell (United States) 12 (12): 3987â99. ISSN 1059-1524. PMC 60770. PMID 11739795. //www.ncbi.nlm.nih.gov/pmc/articles/PMC60770/.
- Clark, Paula A, , Peters Gordon, Peters, Gordon (Jul. 2002). "Multiple interacting domains contribute to p14ARF mediated inhibition of MDM2". Oncogene (England) 21 (29): 4498â507. doi:10.1038/sj.onc.1205558. ISSN 0950-9232. PMID 12085228.
- Pomerantz, J, LiÃ©geois N J, Silverman A, Alland L, Chin L, Potes J, Chen K, Orlow I et al. (Mar. 1998). "The Ink4a tumor suppressor gene product, p19Arf, interacts with MDM2 and neutralizes MDM2's inhibition of p53". Cell (UNITED STATES) 92 (6): 713â23. doi:10.1016/S0092-8674(00)81400-2. ISSN 0092-8674. PMID 9529248.
- Vivo, M, Sansone F, CalabrÃ² V, Parisi T, Borrelli L, Saviozzi S, , La Mantia G, La Mantia, G (Apr. 2001). "The human tumor suppressor arf interacts with spinophilin/neurabin II, a type 1 protein-phosphatase-binding protein". J. Biol. Chem. (United States) 276 (17): 14161â9. doi:10.1074/jbc.M006845200. ISSN 0021-9258. PMID 11278317.
 Further reading
- Smith-SÃ¸rensen B, Hovig E (1996). "CDKN2A (p16INK4A) somatic and germline mutations". Hum. Mutat. 7 (4): 294â303. doi:10.1002/(SICI)1098-1004(1996)7:4<294::AID-HUMU2>3.0.CO;2-9. PMID 8723678.
- Dracopoli NC, Fountain JW (1996). "CDKN2 mutations in melanoma". Cancer Surv. 26: 115â32. PMID 8783570.
- Akita H (2003). "[Prognostic importance of altered expression of cell cycle regulators in lung cancer]". Nippon Rinsho 60 Suppl 5: 267â71. PMID 12101670.
- Kusy S, Larsen CJ, Roche J (2005). "p14ARF, p15INK4b and p16INK4a methylation status in chronic myelogenous leukemia". Leuk. Lymphoma 45 (10): 1989â94. doi:10.1080/10428190410001714025. PMID 15370242.
- Gjerset RA (2007). "DNA damage, p14ARF, nucleophosmin (NPM/B23), and cancer". J. Mol. Histol. 37 (5â7): 239â51. doi:10.1007/s10735-006-9040-y. PMID 16855788.
- Yildiz IZ, UsubÃ¼tÃ¼n A, Firat P et al. (2007). "Efficiency of immunohistochemical p16 expression and HPV typing in cervical squamous intraepithelial lesion grading and review of the p16 literature". Pathol. Res. Pract. 203 (6): 445â9. doi:10.1016/j.prp.2007.03.010. PMID 17543474.
This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.
Cyclin-dependent kinase inhibitor 2a p19Arf N-terminus Provide feedback
This family represents the N-terminus (approximately 50 residues) of cyclin-dependent kinase inhibitor 2a p19Arf, which seems to be restricted to mammals. This is a tumour-suppressor protein that has been shown to inhibit the growth of human tumour cells lacking functional p53 by inducing a transient G2 arrest and subsequently apoptosis .
Eymin B, Leduc C, Coll JL, Brambilla E, Gazzeri S; , Oncogene 2003;22:1822-1835.: p14ARF induces G2 arrest and apoptosis independently of p53 leading to regression of tumours established in nude mice. PUBMED:12660818 EPMC:12660818
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR010868
This entry represents the cyclin-dependent kinase inhibitor 2A, which seems to be restricted to mammals. This is a tumour-suppressor protein that has been shown to inhibit the growth of human tumour cells lacking functional p53 by inducing a transient G2 arrest and subsequently apoptosis [PUBMED:12660818].
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
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|Seed source:||Pfam-B_20449 (release 10.0)|
|Author:||Vella Briffa B|
|Number in seed:||6|
|Number in full:||33|
|Average length of the domain:||50.20 aa|
|Average identity of full alignment:||71 %|
|Average coverage of the sequence by the domain:||51.22 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||7|
|Download:||download the raw HMM for this family|
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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the More....
This chart is a modified "sunburst" visualisation of the species tree for this family. It shows each node in the tree as a separate arc, arranged radially with the superkingdoms at the centre and the species arrayed around the outermost ring.
How the sunburst is generated
The tree is built by considering the taxonomic lineage of each sequence that has a match to this family. For each node in the resulting tree, we draw an arc in the sunburst. The radius of the arc, its distance from the root node at the centre of the sunburst, shows the taxonomic level ("superkingdom", "kingdom", etc). The length of the arc represents either the number of sequences represented at a given level, or the number of species that are found beneath the node in the tree. The weighting scheme can be changed using the sunburst controls.
In order to reduce the complexity of the representation, we reduce the number of taxonomic levels that we show. We consider only the following eight major taxonomic levels:
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Segments of the tree are coloured approximately according to their superkingdom. For example, archeal branches are coloured with shades of orange, eukaryotes in shades of purple, etc. The colour assignments are shown under the sunburst controls. Where space allows, the name of the taxonomic level will be written on the arc itself.
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There are some situations that the sunburst tree cannot easily handle and for which we have work-arounds in place.
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Some species in the taxonomic tree may not have one or more of the main eight levels that we display. For example, Bos taurus is not assigned an order in the NCBI taxonomic tree. In such cases we mark the omitted level with, for example, "No order", in both the tooltip and the lineage summary.
Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
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Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
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The tree shows the occurrence of this domain across different species. More...
We show the species tree in one of two ways. For smaller trees we try to show an interactive representation, which allows you to select specific nodes in the tree and view them as an alignment or as a set of Pfam domain graphics.
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
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Finally, we group sequences from the same organism according to the NCBI code that is assigned by UniProt, allowing us to count the number of distinct sequences on which the domain is found. This value is shown in the pink boxes.
We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the P19Arf_N domain has been found. There are 1 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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