PDE3B can mediate DNMDP sensitivity.
A, DNMDP sensitivity of HUT78 and RVH421, which lack PDE3A mRNA expression, can be competed away by co-treatment with 100 nm trequinsin (Treq) in a 72-h CellTiter-Glo assay. B, immunoblotting reveals that HUT78 and RVH421 do not express any PDE3A protein but do express high levels of PDE3B protein. C (left), CRISPR knockout of PDE3B in the partially sensitive cell line, RVH421, abolished DNMDP sensitivity in a 72-h CellTiter-Glo assay. Right, immunoblot analysis showing loss of PDE3B protein expression in knockout cells made with two PDE3B-specific CRISPR guide RNAs, sg2 and sg5. D (left), ectopic expression of PDE3B in PDE3A knockout A2058 cells restores sensitivity to DNMDP in a 72-h CellTiter-Glo assay. Right, immunoblot analysis showing loss of PDE3A protein and ectopic expression of PDE3B protein in the PDE3A knockout A2058 cells. Vinculin or GAPDH was used a loading control.