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. 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 Mouse 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 each of the other ERBB receptors. Interacts with PDZ domains of DLG2, DLG3, DLG4 and the syntrophin SNTB2. Interacts (via PPxy motifs)with WWOX. Interacts with MUC1. Interacts (via PPxY motif 2) with YAP1 (via WW domain 1). Interacts (isoform JM-A CYT-1 and isoform JM-B CYT-1) with WWP1. Interacts (via the intracellular domains of both JM-A CYT-1 and JM-B CYT-1 isoforms) with TRIM28; the interaction does not phosphorylate TRIM28 but represses ERBB4-mediated transcriptional activity. Interacts with PRPU, DDX23, MATR3, RBM15, ILF3, U5S1, U2SURP, ITCH, HNRPU, AP2A1, NULC, LEO1, WWP2, IGHG1, HXK1, GRB7 AND ARS2 (By similarity). Interacts with CBFA2T3.