Description
Key facts
Detection method:Colorimetric,
Sample types:Nuclear Extracts,
Reacts with:Mouse, Rat, Human,
Assay type:Semi-quantitative,
Sensitivity:< 1250 ng/well,
Assay time:3h 30m,
Assay Platform:Microplate reader
Product details:
JunD Transcription Factor Assay Kit (Colorimetric) (ab207198) is a high throughput assay to quantify JunD activation in nuclear extracts. This assay combines a quick ELISA format with a sensitive and specific non-radioactive assay for transcription factor activation.
A specific double stranded DNA sequence containing the TPA-responsive element (TRE) (5´ –TGAGTCA– 3´) has been immobilized onto a 96-well plate. Activator protein-1 (AP1) present in the nuclear extract specifically binds to the oligonucleotide. AP1 family member JunD is detected by a primary antibody that recognizes an epitope of JunD accessible only when the protein is activated and bound to its target DNA. An HRP-conjugated secondary antibody provides sensitive colorimetric readout at OD 450 nm. This product detects human, mouse and rat JunD.
Key performance and benefits:
Assay time: 3.5 hours (cell extracts preparation not included).
Detection limit: < 1.25 μg nuclear extract/well.
Detection range: 0.1 – 20 μg nuclear extract/well.
The activator protein-1 (AP1) transcription factors belong to a large family of structurally related transcription factors that includes ATF1-4, c-Fos, c-Jun, c-Myc and C/EBP. The members of this family, named bZIP, share a dimerization domain with a leucine zipper motif and a DNA binding domain rich in basic residues (lysines and arginines). AP1 is composed of a mixture of heterodimeric complexes of proteins derived from the Fos and Jun families including c-Fos, FosB, Fra-1, Fra-2, c-Jun, JunB and Jun D. Only Jun proteins can form transcriptionally active homodimers within AP1 members, or heterodimers with CREB/ATF members, to bind the CRE element (5´ - TGACGTCA - 3´). Primarily, AP1 dimers bind to DNA on a TPA-response element (TRE) with the 5´ - TGA(C/G)TCA - 3´ sequence. Jun-Fos heterodimers form more stable complexes with TREs. These complexes display stronger transactivating activity than Jun-Jun homodimers.
Phosphorylation of AP1 family members by kinases is required for transactivation activity. In the case of c-Jun, the activation domain is regulated to a large extent by the JNK family of MAP kinases. JNK kinases phosphorylate c-Jun at Ser-63, resulting in the binding of c-Jun to the CBP/p300 family of transcriptional co-activators. For the Fos proteins, both N- and C-terminal domains flanking the bZIP domain require phosphorylation for biological activity. The kinases responsible for activation remain to be determined.
AP1 expression is induced by multiple stimuli such as serum, growth factors, phorbol esters and oncogenes. These include peptide growth factors, cytokines of the TGF beta, TNF, and interferon families, neuronal depolarization and cellular stress. The total increase in AP1 DNA binding activity after any stimulus is often much less impressive than would be expected based on analysis of mRNA expression. This increase is accompanied by a change in the composition of AP1 complexes shortly after stimulation in order to modulate transcriptional control. Upon serum starvation of human fibroblast cells, Fos and Jun protein production can be induced for up to 4 hours by adding serum. Interestingly, serum starvation lowers basal expression of FosB and c-Fos but has no significant effect on c-Jun.
AP1 proteins play a role in the expression of many genes involved in proliferation and cell cycle progression including neuronal apoptosis, learning process, drug-induced behavorial responses, bone growth and differentiation, and embryo development. For instance, cell transformation by oncogenes that function in the growth factor signal transduction pathway, such as
, results in a high increase in AP1 component protein expression. Therefore, AP1-regulated genes support the invasive process observed during malignancy and metastasis.
Properties and Storage Information:
Shipped at conditions-Dry Ice, Appropriate short-term storage conditions-Multi, Appropriate long-term storage conditions-Multi, Storage information-Please refer to protocols
Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
The JunD transcription factor also known as JunD protein belongs to the AP-1 family of transcription factors. It has a mass of approximately 39 kDa. JunD primarily acts by forming dimers with other proteins such as c-Fos and c-Jun. These dimers bind to specific DNA sequences regulating gene expression. JunD shows expression in various tissues but is more abundant in non-dividing and differentiated cells where it helps modulate specific cellular processes.
Biological function summary
JunD plays a significant role by influencing cellular proliferation and differentiation. It is often part of a multiprotein complex which can include members of the Fos family and other Jun proteins. These complexes interact with DNA to control the transcription of genes involved in cell cycle regulation apoptosis and stress responses. Different stimuli can alter the composition of these complexes highlighting JunD's adaptability in cellular signaling.
Pathways
JunD interacts within the MAPK signaling pathway and the oxidative stress response pathway. In the MAPK pathway it can interact with proteins such as ERK and JNK which are critical mediators of cellular responses to growth factors and stress. In the oxidative stress response JunD regulates genes that protect cells from oxidative damage showing its influence on maintaining cellular homeostasis. Other proteins like ATF2 may also interact with JunD within these pathways contributing to transcriptional regulation.
JunD has connections to cancer and neurodegenerative diseases. Its role in regulating cell proliferation links it to tumorigenesis where alterations in its function can lead to uncontrolled cell growth. Additionally in neurodegenerative disorders JunD's influence on oxidative stress response genes may impact disease progression. Furthermore JunD's interaction with the protein Bcl2 associates it with the protection of cells from apoptotic signals illustrating its potential impact on disease development and progression.
