View source for 8uqr


==Crystal structure of the human p53 tetramerization domain==
<StructureSection load='8uqr' size='340' side='right'caption='[[8uqr]], [[Resolution|resolution]] 1.22&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8uqr]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8UQR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8UQR FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.22&#8491;</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=8uqr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8uqr OCA], [https://pdbe.org/8uqr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8uqr RCSB], [https://www.ebi.ac.uk/pdbsum/8uqr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8uqr ProSAT]</span></td></tr>
</table>
== Disease ==
[https://www.uniprot.org/uniprot/P53_HUMAN P53_HUMAN] Note=TP53 is found in increased amounts in a wide variety of transformed cells. TP53 is frequently mutated or inactivated in about 60% of cancers. TP53 defects are found in Barrett metaplasia a condition in which the normally stratified squamous epithelium of the lower esophagus is replaced by a metaplastic columnar epithelium. The condition develops as a complication in approximately 10% of patients with chronic gastroesophageal reflux disease and predisposes to the development of esophageal adenocarcinoma.  Defects in TP53 are a cause of esophageal cancer (ESCR) [MIM:[https://omim.org/entry/133239 133239].  Defects in TP53 are a cause of Li-Fraumeni syndrome (LFS) [MIM:[https://omim.org/entry/151623 151623]. LFS is an autosomal dominant familial cancer syndrome that in its classic form is defined by the existence of a proband affected by a sarcoma before 45 years with a first degree relative affected by any tumor before 45 years and another first degree relative with any tumor before 45 years or a sarcoma at any age. Other clinical definitions for LFS have been proposed (PubMed:8118819 and PubMed:8718514) and called Li-Fraumeni like syndrome (LFL). In these families affected relatives develop a diverse set of malignancies at unusually early ages. Four types of cancers account for 80% of tumors occurring in TP53 germline mutation carriers: breast cancers, soft tissue and bone sarcomas, brain tumors (astrocytomas) and adrenocortical carcinomas. Less frequent tumors include choroid plexus carcinoma or papilloma before the age of 15, rhabdomyosarcoma before the age of 5, leukemia, Wilms tumor, malignant phyllodes tumor, colorectal and gastric cancers.<ref>PMID:10570149</ref> <ref>PMID:1933902</ref> <ref>PMID:1978757</ref> <ref>PMID:2259385</ref> <ref>PMID:1737852</ref> <ref>PMID:1565144</ref> <ref>PMID:7887414</ref> <ref>PMID:8825920</ref> <ref>PMID:9452042</ref> <ref>PMID:10484981</ref>   Defects in TP53 are involved in head and neck squamous cell carcinomas (HNSCC) [MIM:[https://omim.org/entry/275355 275355]; also known as squamous cell carcinoma of the head and neck.  Defects in TP53 are a cause of lung cancer (LNCR) [MIM:[https://omim.org/entry/211980 211980]. LNCR is a common malignancy affecting tissues of the lung. The most common form of lung cancer is non-small cell lung cancer (NSCLC) that can be divided into 3 major histologic subtypes: squamous cell carcinoma, adenocarcinoma, and large cell lung cancer. NSCLC is often diagnosed at an advanced stage and has a poor prognosis.  Defects in TP53 are a cause of choroid plexus papilloma (CPLPA) [MIM:[https://omim.org/entry/260500 260500]. Choroid plexus papilloma is a slow-growing benign tumor of the choroid plexus that often invades the leptomeninges. In children it is usually in a lateral ventricle but in adults it is more often in the fourth ventricle. Hydrocephalus is common, either from obstruction or from tumor secretion of cerebrospinal fluid. If it undergoes malignant transformation it is called a choroid plexus carcinoma. Primary choroid plexus tumors are rare and usually occur in early childhood.<ref>PMID:12085209</ref>   Defects in TP53 are a cause of adrenocortical carcinoma (ADCC) [MIM:[https://omim.org/entry/202300 202300]. ADCC is a rare childhood tumor of the adrenal cortex. It occurs with increased frequency in patients with the Beckwith-Wiedemann syndrome and is a component tumor in Li-Fraumeni syndrome.<ref>PMID:11481490</ref>   Defects in TP53 are the cause of susceptibility to basal cell carcinoma 7 (BCC7) [MIM:[https://omim.org/entry/614740 614740]. A common malignant skin neoplasm that typically appears on hair-bearing skin, most commonly on sun-exposed areas. It is slow growing and rarely metastasizes, but has potentialities for local invasion and destruction. It usually develops as a flat, firm, pale area that is small, raised, pink or red, translucent, shiny, and waxy, and the area may bleed following minor injury. Tumor size can vary from a few millimeters to several centimeters in diameter.<ref>PMID:21946351</ref> 
== Function ==
[https://www.uniprot.org/uniprot/P53_HUMAN P53_HUMAN] Acts as a tumor suppressor in many tumor types; induces growth arrest or apoptosis depending on the physiological circumstances and cell type. Involved in cell cycle regulation as a trans-activator that acts to negatively regulate cell division by controlling a set of genes required for this process. One of the activated genes is an inhibitor of cyclin-dependent kinases. Apoptosis induction seems to be mediated either by stimulation of BAX and FAS antigen expression, or by repression of Bcl-2 expression. In cooperation with mitochondrial PPIF is involved in activating oxidative stress-induced necrosis; te function is largely independent of transcription. Induces the transcription of long intergenic non-coding RNA p21 (lincRNA-p21) and lincRNA-Mkln1. LincRNA-p21 participates in TP53-dependent transcriptional repression leading to apoptosis and seem to have to effect on cell-cycle regulation. Implicated in Notch signaling cross-over. Prevents CDK7 kinase activity when associated to CAK complex in response to DNA damage, thus stopping cell cycle progression. Isoform 2 enhances the transactivation activity of isoform 1 from some but not all TP53-inducible promoters. Isoform 4 suppresses transactivation activity and impairs growth suppression mediated by isoform 1. Isoform 7 inhibits isoform 1-mediated apoptosis.<ref>PMID:9840937</ref> <ref>PMID:11025664</ref> <ref>PMID:12810724</ref> <ref>PMID:15186775</ref> <ref>PMID:15340061</ref> <ref>PMID:17317671</ref> <ref>PMID:17349958</ref> <ref>PMID:19556538</ref> <ref>PMID:20673990</ref> <ref>PMID:20959462</ref> <ref>PMID:22726440</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The p53 protein is a transcriptional regulatory factor and many of its functions require that it forms a tetrameric structure. Although the tetramerization domain of mammalian p53 proteins (p53TD) share significant sequence similarities, it was recently shown that the tree shrew p53TD is considerably more thermostable than the human p53TD. To determine whether other mammalian species display differences in this domain, we used biophysical, functional, and structural studies to compare the properties of the p53TDs from six mammalian model organisms (human, tree shrew, guinea pig, Chinese hamster, sheep, and opossum). The results indicate that the p53TD from the opossum and tree shrew are significantly more stable than the human p53TD, and there is a correlation between the thermostability of the p53TDs and their ability to activate transcription. Structural analysis of the tree shrew and opossum p53TDs indicated that amino acid substitutions within two distinct regions of their p53TDs can dramatically alter hydrophobic packing of the tetramer, and in particular substitutions at positions corresponding to F341 and Q354 of the human p53TD. Together, the results suggest that subtle changes in the sequence of the p53TD can dramatically alter the stability, and potentially lead to important changes in the functional activity, of the p53 protein.

Highly Similar Tetramerization Domains from the p53 Protein of Different Mammalian Species Possess Varying Biophysical, Functional and Structural Properties.,Sakaguchi S, Nakagawa N, Wahba HM, Wada J, Kamada R, Omichinski JG, Sakaguchi K Int J Mol Sci. 2023 Nov 22;24(23):16620. doi: 10.3390/ijms242316620. PMID:38068946<ref>PMID:38068946</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8uqr" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Homo sapiens]]
[[Category: Large Structures]]
[[Category: Kamada R]]
[[Category: Nakagawa N]]
[[Category: Omichinski JG]]
[[Category: Sakaguchi K]]
[[Category: Sakaguchi S]]
[[Category: Wada J]]
[[Category: Wahba HM]]