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JNK2
c-Jun N-terminal kinases (JNKs), were originally identified as kinases that bind and phosphorylate c-Jun on Ser-63 and Ser-73 within its transcriptional activation domain. They belong to the mitogen-activated protein kinase family, and are responsive to stress stimuli, such as cytokines, ultraviolet irradiation, heat shock, and osmotic shock. They also play a role in T cell differentiation and the cellular apoptosis pathway. Activation occurs through a dual phosphorylation of threonine (Thr) and tyrosine (Tyr) residues within a Thr-Pro-Tyr motif located in kinase subdomain VIII. Activation is carried out by two MAP kinase kinases, MKK4 and MKK7, and JNK can be inactivated by Ser/Thr and Tyr protein phosphatases. It has been suggested that this signaling pathway contributes to inflammatory responses in mammals and insects. Isoforms The c-Jun N-terminal kinases consist of ten isoforms derived from three genes: JNK1 (four isoforms), JNK2 (four isoforms) and JNK3 (two iso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitogen-activated Protein Kinase 9
Mitogen-activated protein kinase 9 is an enzyme that in humans is encoded by the ''MAPK9'' gene. Function The protein encoded by this gene is a member of the MAP kinase family. MAP kinases act as an integration point for multiple biochemical signals, and are involved in a wide variety of cellular processes such as proliferation, differentiation, transcription regulation and development. This kinase targets specific transcription factors, and thus mediates immediate-early gene expression in response to various cell stimuli. It is most closely related to MAPK8, both of which are involved in UV radiation-induced apoptosis, thought to be related to the cytochrome c-mediated cell death pathway. This gene and MAPK8 are also known as c-Jun N-terminal kinases. This kinase blocks the ubiquitination of tumor suppressor p53, and thus it increases the stability of p53 in nonstressed cells. Studies of this gene's mouse counterpart suggest a key role in T-cell differentiation. Four alternati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitogen-activated Protein Kinase
A mitogen-activated protein kinase (MAPK or MAP kinase) is a type of serine/threonine-specific protein kinases involved in directing cellular responses to a diverse array of stimuli, such as mitogens, osmotic stress, heat shock and proinflammatory cytokines. They regulate cell functions including proliferation, gene expression, differentiation, mitosis, cell survival, and apoptosis. MAP kinases are found in eukaryotes only, but they are fairly diverse and encountered in all animals, fungi and plants, and even in an array of unicellular eukaryotes. MAPKs belong to the CMGC (CDK/MAPK/GSK3/CLK) kinase group. The closest relatives of MAPKs are the cyclin-dependent kinases (CDKs). Discovery The first mitogen-activated protein kinase to be discovered was ERK1 (MAPK3) in mammals. Since ERK1 and its close relative ERK2 (MAPK1) are both involved in growth factor signaling, the family was termed "mitogen-activated". With the discovery of other members, even from distant organisms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MAP2K4
Dual-specificity mitogen-activated protein kinase kinase 4 is an enzyme that in humans is encoded by the ''MAP2K4'' gene. ''MAP2K4'' encodes a dual-specificity kinase that belongs to the Ser/Thr protein kinase family. MAP2K4 phosphorylates MAP kinases in response to various environmental stresses or mitogenic stimuli. MAPK8/JNK1, MAPK9/JNK2, and MAPK14/p38 are substrates for MAP2K4, but MAPK1/ERK2 and MAPK3/ERK1 are not phosphorylated by MAP2K4. Structurally, MAP2K4 contains a kinase domain that is phosphorylated and activated by MAP3K1(aka MEKK1). MAP2K4 contains multiple amino acid sites that are phosphorylated and ubiquitinated. Genetic studies using ''Map2k4'' knockout mice revealed embryonic lethality, impaired hepatogenesis and defective liver formation. Analysis of chimeric mice identified a role for ''Map2k4'' in T cell cytokine production and proliferation. ''Map2k4''-deficient chimeric mice frequently develop lymphadenopathy. MAP2K4 is altered in 1.97% of all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MAP2K7
Dual specificity mitogen-activated protein kinase kinase 7, also known as MAP kinase kinase 7 or MKK7, is an enzyme that in humans is encoded by the ''MAP2K7'' gene. This protein is a member of the mitogen-activated protein kinase kinase family. The MKK7 protein exists as six different isoforms with three possible N-termini (α, β, and γ isoforms) and two possible C-termini (1 and 2 isoforms). MKK7 is involved in signal transduction mediating the cell responses to proinflammatory cytokines, and environmental stresses. This kinase specifically activates MAPK8/JNK1 and MAPK9/JNK2, and this kinase itself is phosphorylated and activated by MAP kinase kinase kinases including MAP3K1/MEKK1, MAP3K2/MEKK2, MAP3K3/MEKK5, and MAP4K2/GCK. MKK7 is ubiquitously expressed in all tissue. However, it displays a higher level of expression in skeletal muscle. Multiple alternatively spliced transcript variants encoding distinct isoforms have been found. Nomenclature MAP2K7 is also kno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MKK4
Dual-specificity mitogen-activated protein kinase kinase 4 is an enzyme that in humans is encoded by the ''MAP2K4'' gene. ''MAP2K4'' encodes a dual-specificity kinase that belongs to the Ser/Thr protein kinase family. MAP2K4 phosphorylates MAP kinases in response to various environmental stresses or mitogenic stimuli. MAPK8/JNK1, MAPK9/JNK2, and MAPK14/p38 are substrates for MAP2K4, but MAPK1/ERK2 and MAPK3/ERK1 are not phosphorylated by MAP2K4. Structurally, MAP2K4 contains a kinase domain that is phosphorylated and activated by MAP3K1(aka MEKK1). MAP2K4 contains multiple amino acid sites that are phosphorylated and ubiquitinated. Genetic studies using ''Map2k4'' knockout mice revealed embryonic lethality, impaired hepatogenesis and defective liver formation. Analysis of chimeric mice identified a role for ''Map2k4'' in T cell cytokine production and proliferation. ''Map2k4''-deficient chimeric mice frequently develop lymphadenopathy. MAP2K4 is altered in 1.97% of all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MAPK10
Mitogen-activated protein kinase 10 also known as c-Jun N-terminal kinase 3 (JNK3) is an enzyme that in humans is encoded by the ''MAPK10'' gene. Function The protein encoded by this gene is a member of the MAP kinase family. MAP kinases act as an integration point for multiple biochemical signals, and are involved in a wide variety of cellular processes such as proliferation, differentiation, transcription regulation and development. This protein is a neuronal-specific form of c-Jun N-terminal kinases (JNKs). Through its phosphorylation and nuclear localization, this kinase plays regulatory roles in the signaling pathways during neuronal apoptosis. Beta-arrestin 2, a receptor-regulated MAP kinase scaffold protein, is found to interact with, and stimulate the phosphorylation of this kinase by MAP kinase kinase 4 (MKK4). Cyclin-dependent kinase 5 can phosphorylate, and inhibit the activity of this kinase, which may be important in preventing neuronal apoptosis. Four alternat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Activating Transcription Factor 2
Activating transcription factor 2, also known as ATF2, is a protein that, in humans, is encoded by the ''ATF2'' gene. Function This gene encodes a transcription factor that is a member of the leucine zipper family of DNA-binding proteins. This protein binds to the cAMP-responsive element (CRE), an octameric palindrome. The protein forms a homodimer or heterodimer with c-Jun. The protein is also a histone acetyltransferase (HAT) that specifically acetylates histones H2B and H4 in vitro; thus, it may represent a class of sequence-specific factors that activate transcription by direct effects on chromatin components. Additional transcript variants have been identified but their biological validity has not been determined. The gene atf2 is located at human chromosome 2q32. The protein ATF-2 has 505 amino acids. Studies in mice indicate a role for ATF-2 in the development of nervous system and the skeleton. ATF-2 is normally activated in response to signals that converge on stress ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELK1
ETS Like-1 protein Elk-1 is a protein that in humans is encoded by the ELK1. Elk-1 functions as a transcription activator. It is classified as a ternary complex factor (TCF), a subclass of the ETS family, which is characterized by a common protein domain that regulates DNA binding to target sequences. Elk1 plays important roles in various contexts, including long-term memory formation, drug addiction, Alzheimer's disease, Down syndrome, breast cancer, and Major depressive disorder, depression. Structure As depicted in Figure 1, the Elk1 protein is composed of several domains. Localized in the N-terminal region, the A domain is required for the binding of Elk1 to DNA. This region also contains a nuclear localization signal (NLS) and a nuclear export signal (NES), which are responsible for nuclear import and export, respectively. The B domain allows Elk1 to bind to a dimer of its cofactor, serum response factor (SRF). Located adjacent to the B domain, the R domain is involved in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mothers Against Decapentaplegic Homolog 4
SMAD4, also called SMAD family member 4, Mothers against decapentaplegic homolog 4, or DPC4 (Deleted in Pancreatic Cancer-4) is a highly conserved protein present in all metazoans. It belongs to the SMAD family of transcription factor proteins, which act as mediators of TGF-β signal transduction. The TGFβ family of cytokines regulates critical processes during the lifecycle of metazoans, with important roles during embryo development, tissue homeostasis, regeneration, and immune regulation. SMAD 4 belongs to the co-SMAD group (''common mediator'' SMAD), the second class of the SMAD family. SMAD4 is the only known co-SMAD in most metazoans. It also belongs to the Dwarfin family of proteins that modulate members of the TGFβ protein superfamily, a family of proteins that all play a role in the regulation of cellular responses. Mammalian SMAD4 is a homolog of the ''Drosophila'' protein " Mothers against decapentaplegic" named Medea. SMAD4 interacts with R-Smads, such as SMAD2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSF1
Heat shock factor protein 1 (HSF 1) is a protein that in humans is encoded by the ''HSF1'' gene. HSF1 is highly conserved in eukaryotes and is the primary mediator of transcriptional responses to proteotoxic stress with important roles in non-stress regulation such as development and metabolism. Structure Human HSF1 consists of several domains which regulate its binding and activity. DNA-Binding Domain (DBD) This N-terminal domain of approximately 100 amino acids is the most highly conserved region in the HSF protein family and consists of a helix-turn-helix loop. The DBD of each HSF1 monomer recognizes the sequence nGAAn on target DNA. Repeated sequences of the nGAAn pentamer constitute heat shock elements (HSEs) for active HSF1 trimers to bind. Oligomerization Domain (Leucine Zipper Domains) The two regions responsible for oligomerization between HSF1 monomers are leucine zipper (LZ) domains 1-3 and 4 (these regions are also commonly referred to as HR-A/B and HR-C). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
