growth factor activity

Definition

Target type: molecularfunction

The function that stimulates a cell to grow or proliferate. Most growth factors have other actions besides the induction of cell growth or proliferation. [ISBN:0815316194]

Growth factors are signaling molecules that stimulate cell growth, proliferation, differentiation, and survival. They exert their effects by binding to specific receptors on the cell surface, triggering intracellular signaling pathways that ultimately lead to changes in gene expression and protein synthesis. The molecular function of growth factor activity encompasses several key steps:

1. **Ligand Binding:** Growth factors bind to their cognate receptors, initiating a conformational change in the receptor. This binding event is highly specific and is characterized by a high affinity between the ligand and the receptor.

2. **Receptor Dimerization and Activation:** Upon ligand binding, receptor monomers dimerize, forming a complex that activates the intrinsic tyrosine kinase activity of the receptor. This kinase activity is essential for downstream signaling.

3. **Phosphorylation Cascade:** Activated receptors phosphorylate specific tyrosine residues on themselves and on other proteins within the signaling pathway. This phosphorylation cascade amplifies the initial signal and propagates it to downstream effectors.

4. **Activation of Signaling Pathways:** Phosphorylated proteins activate a variety of intracellular signaling pathways, including the Ras-MAPK pathway, the PI3K-Akt pathway, and the JAK-STAT pathway. These pathways regulate transcription factors that control gene expression, ultimately leading to changes in cell behavior.

5. **Regulation of Gene Expression:** Activated signaling pathways influence the expression of genes involved in cell growth, proliferation, differentiation, and survival. The specific genes targeted by a particular growth factor depend on the cell type and the signaling pathways involved.

6. **Cellular Response:** Changes in gene expression lead to a variety of cellular responses, including increased cell size, proliferation, differentiation, and survival. Growth factors play a crucial role in development, tissue repair, and wound healing.

7. **Homeostasis and Regulation:** Growth factor activity is tightly regulated to ensure proper cell growth and development. Dysregulation of growth factor signaling is implicated in various diseases, including cancer and developmental disorders.'
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Proteins (17)

Compounds (128)