Acts as a scaffolding protein that can activate the inflammatory transcription factor NF-kappa-B and p38/JNK MAP kinase signaling pathways. Forms a signaling complex with BCL10 and MALT1, and activates MALT1 proteolytic activity and inflammatory gene expression. MALT1 is indispensable for CARD14-induced activation of NF-kappa-B and p38/JNK MAP kinases (PubMed:11278692, PubMed:21302310, PubMed:27071417, PubMed:27113748). May play a role in signaling mediated by TRAF2, TRAF3 and TRAF6 and protects cells against apoptosis. ; [Isoform 3]: Not able to activate the inflammatory transcription factor NF-kappa-B and may function as a dominant negative regulator (PubMed:21302310, PubMed:26358359).