Multicellular organisms live in a complex milieu where signaling pathways play a key role in their survival. As important mediators of this signal cascade, tyrosine kinases exert critical effects in various
biological processes such as growth, differentiation, metabolism, and apoptosis in response to internal and external stimuli. Among the 90 unique tyrosine kinase genes identified in the human genome, 58
encode receptor tyrosine kinases (RTKs)  . Here we provide a brief overview of the RTK superfamily, classification, functions, their regulatory mechanisms in cells, and related
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