“…4 ). Altogether, an incomplete list of the proteins that apparently mediate ERBB4 function via physical and functional interactions with the ERBB4 cytoplasmic domain includes the Rous sarcoma virus protein tyrosine kinase (SRC); the Abelson-related protein tyrosine kinase (ABL2); the spleen-associated protein tyrosine kinase (SYK); the Janus kinase 1 (JAK1); protein tyrosine phosphatase non-receptor type 11 (PTPN11); phospholipase C gamma-2 (PLCG2); phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform (PIK3CA) via its p85 regulatory subunit; the Casitas B-lineage lymphoma ubiquitin ligase (CBL); the second guanine nucleotide exchange factor named after the sixth letter of the Greek alphabet (VAV2); the rat sarcoma virus protein (RAS) GTPase activating protein RASA1; the signal transducer and activator transcription factors STAT1 and STAT5a; the Yes-associated protein 1 (YAP1); the tumor suppressor oxidoreductase WWOX; postsynpatic density protein 95 (PSD-95), which binds the PDZ-domain recognition motif at the carboxyl terminus of ERBB4; and several adapter proteins, including the SRC homology domain 2-containing transforming protein (SHC1), growth factor receptor-bound protein 2 (GRB2), growth factor receptor-bound protein 7 (GRB7), CT10 regulator of kinase (CRK), and the CRK-like protein (CRKL) ( Culouscou et al, 1995 ; Sepp-Lorenzino et al, 1996 ; Elenius et al, 1997b ; Fiddes et al, 1998 ; Olayioye et al, 1998 ; Pinkas-Kramarski et al, 1998b ; Wang et al, 1998 ; Elenius et al, 1999 ; Jones et al, 1999 ; Olayioye et al, 1999 ; Garcia et al, 2000 ; Huang et al, 2000 , 2002 ; Sweeney et al, 2000 ; Puricelli et al, 2002 ; Carpenter, 2003a ,b; Schulze et al, 2005 ; Chuu et al, 2008 ; Kaushansky et al, 2008 ; Ishibashi et al, 2013 ; Roskoski, 2014 ; Li et al, 2015 ; Wang, 2017 ; Segers et al, 2020 ). Section II.H , which is focused on signaling by the soluble ERBB4 cytoplasmic domain (4ICD), further discusses ERBB4 signaling effectors, some of which are not mentioned in Section II.D .…”