We selected DGKζ for comparative studies with DGKα because expression of these isoforms is enriched in T cells where they function as negative regulators of TCR signaling and are emerging as promising targets for cancer immunotherapy.13,22,46 We produced chimeras that evaluated DGKζ C1 domains engrafted into the DGKα protein backbone (DGKαC1ζ) and the corresponding C1 domain swapped counterpart (DGKζC1α, Fig. 4(A)). Here, DGKA is linked to cancer.