FIG. 3.

Analysis of ER and Golgi complex stored Ca²⁺ in cells expressing picornavirus 2B proteins. BGM cells were cotransfected with ER-targeted (A) or Golgi complex-targeted (B) aequorin and the indicated 2B-myc constructs. At 24 h posttransfection, ER and Golgi complex stores were depleted of Ca²⁺ and the aequorins were reconstituted with coelenterazine. Cells were perfused with HT medium without Ca²⁺ and subsequently with HT medium supplemented with 1 mM free Ca²⁺. The recorded aequorin luminescence data were calibrated offline into [Ca²⁺] values. Representative traces are shown for CBV3 2B. (A) ER Ca²⁺ levels were reduced in cells expressing CBV3, PV1, HRV14, or EMCV 2B but not in cells expressing HAV 2B. (B) Golgi complex Ca²⁺ levels were reduced in cells expressing CBV3, PV1, or HRV14 2B but not in cells expressing HAV or EMCV 2B.