Growth arrest and DNA-damage-inducible, beta, also known as GADD45B, is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 which in humans is encoded by the GADD45B gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

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Function

This gene is a member of a group of genes whose transcript levels are increased following stressful growth arrest conditions and treatment with DNA-damaging agents. The genes in this group respond to environmental stresses by mediating activation of the p38

P38 mitogen-activated protein kinases

P38 mitogen-activated protein kinases are a class of mitogen-activated protein kinases that are responsive to stress stimuli, such as cytokines, ultraviolet irradiation, heat shock, and osmotic shock, and are involved in cell differentiation and apoptosis....

/JNK

C-Jun N-terminal kinases

c-Jun N-terminal kinases , 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...

 pathway. This activation is mediated via their proteins binding and activating MTK1/MEKK4

MAP3K4

Mitogen-activated protein kinase kinase kinase 4 is an enzyme that in humans is encoded by the MAP3K4 gene.-Interactions:MAP3K4 has been shown to interact with GADD45G, GADD45B and GADD45A.-Further reading:...

 kinase, which is an upstream activator of both p38 and JNK MAPK

Mitogen-activated protein kinase

Mitogen-activated protein kinases are serine/threonine-specific protein kinases that respond to extracellular stimuli and regulate various cellular activities, such as gene expression, mitosis, differentiation, proliferation, and cell survival/apoptosis.-Activation:MAP kinases are activated...

s. The function of these genes or their protein products is involved in the regulation of growth and apoptosis

Apoptosis

Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...

. These genes are regulated by different mechanisms, but they are often coordinately expressed and can function cooperatively in inhibiting cell growth.

Gadd45b is required for activity-induced DNA demethylation

DNA demethylation

DNA demethylation is a process of removal of methyl group from nucleotide in DNA. DNA demethylation could be passive and active. Passive process takes place in the absence of methylation of newly synthesised DNA strands by DNMT1 during several replication rounds...

 of specific promoters and expression of corresponding genes necessary for adult neurogenesis

Neurogenesis

Neurogenesis is the process by which neurons are generated from neural stem and progenitor cells. Most active during pre-natal development, neurogenesis is responsible for populating the growing brain with neurons. Recently neurogenesis was shown to continue in several small parts of the brain of...

, including brain-derived neurotrophic factor

Brain-derived neurotrophic factor

Brain-derived neurotrophic factor, also known as BDNF, is a protein that, in humans, is encoded by the BDNF gene. BDNF is a member of the "neurotrophin" family of growth factors, which are related to the canonical "Nerve Growth Factor", NGF...

 and fibroblast growth factor

Fibroblast growth factor

Fibroblast growth factors, or FGFs, are a family of growth factors involved in angiogenesis, wound healing, and embryonic development. The FGFs are heparin-binding proteins and interactions with cell-surface associated heparan sulfate proteoglycans have been shown to be essential for FGF signal...

. Hence GADD45B is implicated in affecting synaptic plasticity

Synaptic plasticity

In neuroscience, synaptic plasticity is the ability of the connection, or synapse, between two neurons to change in strength in response to either use or disuse of transmission over synaptic pathways. Plastic change also results from the alteration of the number of receptors located on a synapse...

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Interactions

GADD45B has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with MAP3K4

MAP3K4

Mitogen-activated protein kinase kinase kinase 4 is an enzyme that in humans is encoded by the MAP3K4 gene.-Interactions:MAP3K4 has been shown to interact with GADD45G, GADD45B and GADD45A.-Further reading:...

, ASK1

ASK1

Apoptosis signal-regulating kinase 1 also known as mitogen-activated protein kinase kinase kinase 5 is a member of MAP kinase kinase kinase family and as such a part of mitogen-activated protein kinase pathway...

, MAP2K7

MAP2K7

Mitogen-activated protein kinase kinase 7, also known as MAP2K7, is ahuman gene.-Interactions:MAP2K7 has been shown to interact with GADD45B, MAPK8, MAPK8IP3, MAPK8IP1, MAP3K12, MAP3K2, MAPK8IP2 and DUSP19.-Further reading:...

 and GADD45GIP1

GADD45GIP1

Growth arrest and DNA-damage-inducible proteins-interacting protein 1 is a protein that in humans is encoded by the GADD45GIP1 gene.-Interactions:GADD45GIP1 has been shown to interact with GADD45G, GADD45B and GADD45A.-Further reading:...

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Further reading