p53 (TP53 gene) acts as a tumor suppressor in many tumor types and induces growth arrest or apoptosis depending on the physiological circumstances and cell type. p53 is 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. p53 mediated apoptosis induction seems to be by stimulation of BAX and FAS antigen expression, or by repression of Bcl-2 expression. p53 is also implicated in Notch signaling cross-over.
ab124533 p53 Phospho S392 Human ELISA (Enzyme-Linked Immunosorbent Assay) kit is an in vitro enzyme-linked immunosorbent assay for the accurate quantitative measurement of phosphorylated Ser392 of p53 protein in human cell and tissue lysates. The assay employs a p53 protein specific antibody coated onto well plate strips.
Samples are pipetted into the wells and p53 present in the sample is bound to the wells by the immobilized antibody. The wells are washed and an anti-p53 phospho Ser392 detector antibody is added. After washing away unbound detector antibody, HRP-conjugated label specific for the detector antibody is pipetted into the wells. The wells are again washed, a TMB substrate solution is added to the wells and color develops in proportion to the amount of phosphorylated Ser392 of bound p53. The developing blue color is measured at 600 nm.
Optionally the reaction can be stopped by adding hydrochloric acid which changes the color from blue to yellow and the intensity can be measured at 450 nm.
ab124533 detects phosphorylated Ser392 of p53 in Human samples only.
Typical working ranges:
Hek293T cells (Etoposide treated): 12 – 800 µg/ml
MCF7 cells (Camptothecin treated): 12 – 400 µg/ml
Store all components at 4°C. This kit is stable for 6 months from receipt. Unused microplate strips should be returned to the pouch containing the desiccant and resealed. After opening, the unused Incubation Buffer should be stored at -20°C.
FunctionActs 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. Implicated in Notch signaling cross-over. 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.
Tissue specificityUbiquitous. Isoforms are expressed in a wide range of normal tissues but in a tissue-dependent manner. Isoform 2 is expressed in most normal tissues but is not detected in brain, lung, prostate, muscle, fetal brain, spinal cord and fetal liver. Isoform 3 is expressed in most normal tissues but is not detected in lung, spleen, testis, fetal brain, spinal cord and fetal liver. Isoform 7 is expressed in most normal tissues but is not detected in prostate, uterus, skeletal muscle and breast. Isoform 8 is detected only in colon, bone marrow, testis, fetal brain and intestine. Isoform 9 is expressed in most normal tissues but is not detected in brain, heart, lung, fetal liver, salivary gland, breast or intestine.
Involvement in diseaseNote=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]. 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.
Sequence similaritiesBelongs to the p53 family.
DomainThe nuclear export signal acts as a transcriptional repression domain. The TADI and TADII motifs (residues 17 to 25 and 48 to 56) correspond both to 9aaTAD motifs which are transactivation domains present in a large number of yeast and animal transcription factors.
Post-translational modificationsAcetylated. Acetylation of Lys-382 by CREBBP enhances transcriptional activity. Deacetylation of Lys-382 by SIRT1 impairs its ability to induce proapoptotic program and modulate cell senescence. Phosphorylation on Ser residues mediates transcriptional activation. Phosphorylated by HIPK1 (By similarity). Phosphorylation at Ser-9 by HIPK4 increases repression activity on BIRC5 promoter. Phosphorylated on Thr-18 by VRK1. Phosphorylated on Ser-20 by CHEK2 in response to DNA damage, which prevents ubiquitination by MDM2. Phosphorylated on Thr-55 by TAF1, which promotes MDM2-mediated degradation. Phosphorylated on Ser-46 by HIPK2 upon UV irradiation. Phosphorylation on Ser-46 is required for acetylation by CREBBP. Phosphorylated on Ser-392 following UV but not gamma irradiation. Phosphorylated upon DNA damage, probably by ATM or ATR. Phosphorylated on Ser-15 upon ultraviolet irradiation; which is enhanced by interaction with BANP. Dephosphorylated by PP2A-PPP2R5C holoenzyme at Thr-55. SV40 small T antigen inhibits the dephosphorylation by the AC form of PP2A. May be O-glycosylated in the C-terminal basic region. Studied in EB-1 cell line. Ubiquitinated by MDM2 and SYVN1, which leads to proteasomal degradation. Ubiquitinated by RFWD3, which works in cooperation with MDM2 and may catalyze the formation of short polyubiquitin chains on p53/TP53 that are not targeted to the proteasome. Ubiquitinated by MKRN1 at Lys-291 and Lys-292, which leads to proteasomal degradation. Deubiquitinated by USP10, leading to its stabilization. Ubiquitinated by TRIM24, which leads to proteasomal degradation. Ubiquitination by TOPORS induces degradation. Deubiquitination by USP7, leading to stabilization. Isoform 4 is monoubiquitinated in an MDM2-independent manner. Monomethylated at Lys-372 by SETD7, leading to stabilization and increased transcriptional activation. Monomethylated at Lys-370 by SMYD2, leading to decreased DNA-binding activity and subsequent transcriptional regulation activity. Lys-372 monomethylation prevents interaction with SMYD2 and subsequent monomethylation at Lys-370. Dimethylated at Lys-373 by EHMT1 and EHMT2. Monomethylated at Lys-382 by SETD8, promoting interaction with L3MBTL1 and leading to repress transcriptional activity. Demethylation of dimethylated Lys-370 by KDM1A prevents interaction with TP53BP1 and represses TP53-mediated transcriptional activation. Sumoylated by SUMO1.
Cellular localizationCytoplasm; Cytoplasm. Nucleus. Nucleus > PML body. Endoplasmic reticulum. Interaction with BANP promotes nuclear localization. Recruited into PML bodies together with CHEK2; Nucleus. Cytoplasm. Localized in both nucleus and cytoplasm in most cells. In some cells, forms foci in the nucleus that are different from nucleoli; Nucleus. Cytoplasm. Localized in the nucleus in most cells but found in the cytoplasm in some cells; Nucleus. Cytoplasm. Localized mainly in the nucleus with minor staining in the cytoplasm; Nucleus. Cytoplasm. Predominantly nuclear but localizes to the cytoplasm when expressed with isoform 4 and Nucleus. Cytoplasm. Predominantly nuclear but translocates to the cytoplasm following cell stress.
The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.
Use at an assay dependent concentration.
Human p53 Phospho S392 ELISA Kit images
Sandwich ELISA - p53 Phospho S392 Human ELISA Kit (ab124533)
Example positive control sample standard curve. A dilution series of extract in Incubation Buffer in the working range of the assay. The extract was prepared from Hek293T cells treated with Etoposide by direct lysis (Protocol Booklet Section 7.2).
Sandwich ELISA - p53 Phospho S392 Human ELISA Kit (ab124533)
Example experimental analysis of drug treatment of Hek 293T and MCF7 cells. Cells were treated with Camptothecin, Etoposide or drug’s vehicle, as indicated. Diluted cell extracts (Hek293T to 200 µg/mL and MCF7 to 100 µg/mL) were analyzed by this kit (A, D, G) and p53 protein ELISA (B, E, H, using ab117995). Extract of Hek 293T treated with Etoposide was used for positive control sample standard curves. Relative levels interpolated from standard curves are shown. The levels of phosphorylated Ser392 normalized to total p53 protein levels were obtained as a ratio of phospho Ser392 and p53 protein levels (C, F, I).
Sandwich ELISA - p53 Phospho S392 Human ELISA Kit (ab124533)
The p53 Phospho S392 ELISA specifically measures the phosphorylated Serine. In green: extracts of Hek 293T cells (induced with Etoposide) were treated with increasing concentrations of λ protein phosphatase or left untreated (Contr), and phospho Ser392 and total p53 protein levels were determined, respectively, using this kit and ab117995. In red: extracts of Hek 293T cells (induced with Etoposide) were immunocaptured to the plate, the immunocaptured materials were treated with increasing concentrations of λ protein phosphatase or left untreated (Contr), and phospho Ser392 and total p53 protein levels were determined using, respectively, this kit and ab117995. Dilutions of extracts of Hek 293T cells treated with Etoposide were used to construct the standard curves.
Western blot - p53 Phospho S392 Human ELISA Kit (ab124533)
The detector antibody used in this kit specifically detects the phosphorylated p53 as determined by Western blotting. Extracts of Hek 293T cells (induced with Etoposide) were treated with increasing concentrations of λ protein phosphatase (lane 2, 400x diluted; lane 3, 100x diluted; lane 4, 25x diluted) or left untreated (lane 1). Samples were analyzed by Western blotting using the p53 Phospho S392 Detector Antibody (A). The membrane was re-probed to detect total p53 protein using the capture antibody of this kit (B).