Kasvutekijäsignalointi

Kasvutekijäsignalointi, often translated as growth factor signaling, is a fundamental biological process that regulates cell growth, differentiation, and survival. These signals are typically initiated by secreted proteins called growth factors, which bind to specific receptors on the surface of target cells. This binding event triggers a cascade of intracellular events, often involving phosphorylation of signaling molecules.

The receptor, upon growth factor binding, activates intracellular proteins. This activation frequently involves the recruitment of adapter proteins and the activation of enzymes such as kinases. These activated enzymes then phosphorylate other downstream proteins, propagating the signal. This molecular relay race can involve multiple steps and different types of signaling pathways, such as the MAPK or PI3K pathways.

Ultimately, the signal transduction culminates in changes in gene expression or protein activity within the cell. These alterations can lead to a variety of cellular responses, including cell division (proliferation), specialization into different cell types (differentiation), or programmed cell death (apoptosis). This tightly regulated process is crucial for normal development, tissue repair, and maintaining homeostasis. Dysregulation of growth factor signaling can contribute to diseases such as cancer, where uncontrolled cell proliferation is a hallmark. Understanding these pathways is therefore vital for developing therapeutic strategies for various human conditions.