PIP3 activates AKT signaling PathwayStep5380 PathwayStep5379 PathwayStep5378 Conversion of PIP2 into PIP3 by PI3K bound to p-ERBB4cyt1 homodimers Binding of p85 subunit of PI3K (PIK3R1) to p-ERBB4cyt1 homodimers Recruitment of PI3K subunit p110 (PIK3CA) to PI3K subunit p85 (PIK3R1) bound to p-ERBB4cyt1 homodimers PI3K events in ERBB4 signaling Authored: Orlic-Milacic, M, 2011-11-04 Edited: Matthews, L, 2011-11-07 Reactome Database ID Release 431250342 Reactome, http://www.reactome.org ReactomeREACT_115961 Reviewed: Earp HS, 3rd, 2012-02-20 Reviewed: Harris, RC, 2011-11-11 Reviewed: Misior, AM, 2012-02-20 Reviewed: Zeng, F, 2011-11-11 The CYT1 isoforms of ERBB4 possess a C-tail tyrosine residue that, upon trans-autophosphorylation, serves as a docking site for the p85 alpha subunit of PI3K - PIK3R1 (Kaushansky et al. 2008, Cohen et al. 1996). Binding of PIK3R1 to CYT1 isoforms of ERBB4 is followed by recruitment of the p110 catalytic subunit of PI3K (PIK3CA), leading to assembly of an active PI3K complex that converts PIP2 to PIP3 and activates AKT signaling (Kainulainen et al. 2000). PathwayStep3897