Final answer:
Receptor tyrosine kinases are critical for cellular communication and involve a process of extracellular signal binding, dimerization, autophosphorylation, and initiation of downstream responses.
Step-by-step explanation:
Receptor tyrosine kinases (RTKs) are a class of enzyme-linked receptors essential for cellular communication and signal transduction. RTKs consist of a single transmembrane region, with distinct extracellular and intracellular domains.
When a signaling molecule, such as epidermal growth factor, binds to the extracellular domain, it provokes the dimerization of two RTK molecules. This event leads to the autophosphorylation of tyrosine residues within the intracellular domain, activating the receptors and enabling them to initiate a downstream cellular response. An example of how RTKs function is demonstrated by the epidermal growth factor receptor (EGFR), where its activation can promote cellular proliferation.
However, mutations in these pathways can contribute to diseases like multiple sclerosis, Alzheimer's disease or cancer. Moreover, receptor signaling is finely regulated as phosphatases can deactivate the pathway by removing phosphate groups from the tyrosine residues.