it is not known whether this signalling pathway is involved in initiating dna replication , whereas it has been firmly established that reinitiation of dna synthesis can be triggered without activation of ptdins ( 4,5 ) p2 hydrolysis by , for example , egf ( epidermal growth factor ) , fgf ( fibroblast growth factor ) and insulin/igf-i ( insulin-like growth factor-i ) , members of a class of mitogens known to activate receptor tyrosine kinases .
C0037083
signalling pathway
C0206364
receptor