3tg5

Structure of SMYD2 in complex with p53 and SAHStructure of SMYD2 in complex with p53 and SAH

Structural highlights 3tg5 is a 2 chain structure with sequence from Human. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: , , Related: 3tg4 Gene: SMYD2, KMT3C (HUMAN) Resources: FirstGlance, OCA, RCSB, PDBsum Disease [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:133239]. Defects in TP53 are a cause of Li-Fraumeni syndrome (LFS) [MIM: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. Defects in TP53 are involved in head and neck squamous cell carcinomas (HNSCC) [MIM:275355]; also known as squamous cell carcinoma of the head and neck. Defects in TP53 are a cause of lung cancer (LNCR) [MIM: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: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. Defects in TP53 are a cause of adrenocortical carcinoma (ADCC) [MIM: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. Defects in TP53 are the cause of susceptibility to basal cell carcinoma 7 (BCC7) [MIM: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. Function [SMYD2_HUMAN] Protein-lysine N-methyltransferase that methylates both histones and non-histone proteins. Specifically methylates histone H3 'Lys-4' (H3K4me) and dimethylates histone H3 'Lys-36' (H3K36me2). Has also methyltransferase activity toward non-histone proteins such as p53/TP53 and RB1. Monomethylates 'Lys-370' of p53/TP53, leading to decreased DNA-binding activity and subsequent transcriptional regulation activity of p53/TP53. Monomethylates 'Lys-860' of RB1/RB. [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. Publication Abstract from PubMed SMYD2 belongs to a sub-family of histone lysine methyltransferase (HKMT) and was recently identified to methylate tumor suppressor p53 and Rb. Here we report that SMYD2 prefers to methylate p53 K370 than histone substrates in vitro. Consistently, the level of endogenous p53 K370 mono-methylation is significantly elevated when SMYD2 is overexpressed in vivo. We have solved the high resolution crystal structures of the full length SMYD2 protein in binary complex with its cofactor SAM and in ternary complex with cofactor product S-adenosylhomocysteine (AdoHcy) and p53 substrate peptide (368-375), respectively. P53 peptide binds to a deep pocket of the interface between catalytic SET (1-282) and C-terminal domain (CTD) with a unpredecent U-shaped conformation. Subtle conformational change exists around p53 binding site between the binary and ternary structures, in particular, the tetratrico-peptide repeat (TPR) motif of the CTD. In addition, a unique EDEE motif between the loop of anti-parallel beta7 and beta8 sheets of the SET core not only interacts with p53 substrate but also forms hydrogen bond network with residues from CTD. These observations suggest that the TPR and EDEE motif may play an important role in determining p53 substrate binding specificity. This is further verified by the results that deletion of the CTD domain drastically reduces the methylation activity of SMYD2 to p53 protein. Meanwhile, mutation of EDEE residues impairs both the binding and the enzymatic activity of SMYD2 to p53 K370. These data together reveal the molecular basis of SMYD2 in specifically recognizing and regulating functions of p53 tumor suppressor through K370 mono-methylation. Structure of human SMYD2 reveals the basis of p53 tumor suppressor methylation.,Wang L, Li L, Zhang H, Luo X, Dai J, Zhou S, Gu J, Zhu J, Atadja P, Lu C, Li E, Zhao K J Biol Chem. 2011 Aug 31. PMID:21880715 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Histone methyltransferase

spinqualitylabelsall models 3tg5, resolution 2.30Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image