biostudies-literatureRios KENational Institute of Allergy and Infectious DiseasesNIAID NIH HHSNational Institute of General Medical SciencesNIGMS NIH HHS104179https://www.ebi.ac.uk/biostudies/studies/S-EPMC7484395biostudies-literatureUnknown356After T cell receptor (TCR) engagement, the CARD11-Bcl10-Malt1 (CBM) complex oligomerizes to transduce NF-κB activating signals. Bcl10 is then degraded to limit NF-κB activation. The cDNA AK057716 (BinCARD-1) was reported to encode a novel CARD protein that interacts with Bcl10 and modestly inhibits NF-κB activation. In a later study, a second isoform, BinCARD-2, was identified. Here, we report that the cDNA AK057716 (BinCARD-1) is an incompletely spliced derivative of the gene product of C9orf89, whereas CARD19 (BinCARD-2) represents the properly spliced isoform, with conservation across diverse species. Immunoblotting revealed expression of CARD19 in T cells, but no evidence of BinCARD-1 expression, and microscopy demonstrated that endogenous CARD19 localizes to mitochondria. Although weCellular immunologyCARD19, the protein formerly known as BinCARD, is a mitochondrial protein that does not regulate Bcl10-dependent NF-κB activation after TCR engagement.PMC7484395U01 GM109887R01 AI125552Rios KEMaynard SKWashington MSchaefer BCPaul SKashyap AKfalseCARD19, the protein formerly known as BinCARD, is a mitochondrial protein that does not regulate Bcl10-dependent NF-κB activation after TCR engagement.After T cell receptor (TCR) engagement, the CARD11-Bcl10-Malt1 (CBM) complex oligomerizes to transduce NF-κB activating signals. Bcl10 is then degraded to limit NF-κB activation. The cDNA AK057716 (BinCARD-1) was reported to encode a novel CARD protein that interacts with Bcl10 and modestly inhibits NF-κB activation. In a later study, a second isoform, BinCARD-2, was identified. Here, we report that the cDNA AK057716 (BinCARD-1) is an incompletely spliced derivative of the gene product of C9orf89, whereas CARD19 (BinCARD-2) represents the properly spliced isoform, with conservation across diverse species. Immunoblotting revealed expression of CARD19 in T cells, but no evidence of BinCARD-1 expression, and microscopy demonstrated that endogenous CARD19 localizes to mitochondria. Although we2020-01-01T00:00:00Z2020 Oct2026-05-07T19:36:06.801Z2022-02-11T11:41:25.268ZS-EPMC74843953276350210.1016/j.cellimm.2020.104179