Specifically binds and is activated by neuregulins, including NRG2 and NRG3, HBEGF, BTC and NTAK. Interaction with these factors induces cell differentiation. Plays a role in the regulation of cell growth and cell proliferation. Not activated by EGF, TGF-A, and AREGAREGB. The C-terminal fragment (CTF) of isoform JMA-A CYT-2 (containing E4ICD2) can stimulate transcription in the presence of YAP1. Conflicting reports are likely due at least in part to the opposing effects of the isoform-specific and nuclear-translocated ERBB4 intracellular domains (E4ICD1 and E4ICD2). Overexpression studies in epithelium show growth inhibition using E4ICD1 and increased proliferation using E4ICD2. E4ICD2 has greater in vitro kinase activity than E4ICD1. The kinase activity is required for the nuclear translocation of E4ICD2.
Specificity
Natural and recombinant Human Receptor tyrosine-protein kinase erbB-4
Subcellular Location
ERBB4 intracellular domain Nucleus Following proteolytical processing E4ICD (E4ICD1 or E4ICD2 generated from the respective isoforms) is translocated to the nucleus. Significantly more E4ICD2 than E4ICD1 is found in the nucleus. E4ICD2 colocalizes with YAP1 in the nucleus.
Homodimer or heterodimer with another ERBB family member (By similarity). Interacts with CBFA2T3 (By similarity). Interacts with DLG2 (via its PDZ domain), DLG3 (via its PDZ domain), DLG4 (via its PDZ domain) and SNTB2 (via its PDZ domain). Interacts with MUC1. Interacts (via its PPxy motifs) with WWOX. Interacts (via the PPxY motif 3 of isoform JM-A CYT-2) with YAP1 (via the WW domain 1 of isoform 1). Interacts (isoform JM-A CYT-1 and isoform JM-B CYT-1) with WWP1. Interacts (via its intracellular domain) with TRIM28. Interacts (via the intracellular domains of both CYT-1 and CYT-2 isoforms) with KAP1; the interaction does not phosphorylate KAP1 but represses ERBB4-mediated transcriptional activity. Interacts with PRPU, DDX23, MATR3, RBM15, ILF3, KAP1, U5S1, U2SURP, ITCH, HNRPU, AP2A1, NULC, LEO1, WWP2, IGHG1, HXK1, GRB7 AND ARS2.