Transforming growth factor beta
Transforming Growth Factor Beta[edit]
Transforming Growth Factor Beta (TGF-_) is a multifunctional peptide that controls proliferation, cellular differentiation, and other functions in most cells. It belongs to the transforming growth factor beta superfamily of cytokines.
Structure[edit]
TGF-_ is a secreted protein that exists in three isoforms in mammals: TGF-_1, TGF-_2, and TGF-_3. These isoforms are encoded by separate genes and are highly conserved across species. The active form of TGF-_ is a dimeric protein that is stabilized by a disulfide bond.
Function[edit]
TGF-_ plays a crucial role in cellular processes such as cell growth, apoptosis, and cellular differentiation. It is involved in the regulation of the immune system, wound healing, and embryonic development. TGF-_ signaling is initiated when the ligand binds to a type II receptor, which then recruits and phosphorylates a type I receptor. This receptor complex then phosphorylates receptor-regulated SMADs (R-SMADs), which translocate to the nucleus to regulate gene expression.
Signaling Pathway[edit]
The TGF-_ signaling pathway involves several key components, including the TGF-_ receptors, SMAD proteins, and various co-factors. Upon ligand binding, the type II receptor phosphorylates the type I receptor, which in turn phosphorylates R-SMADs. These R-SMADs form a complex with co-SMADs and translocate to the nucleus to regulate target gene expression.
Role in Disease[edit]
TGF-_ is implicated in various diseases, including cancer, fibrosis, and autoimmune disorders. In cancer, TGF-_ can act as both a tumor suppressor and a tumor promoter, depending on the context. It is known to inhibit the early stages of tumor development but can promote tumor progression and metastasis in later stages.
Therapeutic Applications[edit]
Due to its involvement in numerous pathological conditions, TGF-_ is a target for therapeutic intervention. Strategies include the use of TGF-_ inhibitors, receptor blockers, and antisense oligonucleotides to modulate its activity in diseases such as cancer and fibrosis.
Related Pages[edit]
References[edit]
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Transforming growth factor beta
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SMAD apoptosis pathway
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DAXX Pathway
