SERCA activity is required for timely progression through G1/S.

V R Simon; M F Moran

doi:10.1046/j.1365-2184.2001.00192.x

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SERCA activity is required for timely progression through G1/S.

V R Simon·M F Moran

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Abstract

Changes in intracellular Ca2+ correlate with specific events in the cell cycle. Here we investigated the role of Ca2+ in the G1 phase. HEK 293 cells were arrested in mitosis and subjected to short-term treatments that alter Ca2+ homeostasis prior to their release into G1. Treatment with thapsigargin (TG), an irreversible inhibitor of the sarco-endoplasmic reticulum Ca2+ ATPase (SERCA) lengthened the G1 phase. Moreover, TG treatment also resulted in a dramatic alteration in cellular morphology and attachment and in the reduction of MAPK activity and lower levels of cyclin D1 and cyclin E proteins. Treatments with reagents that transiently increase or decrease cytosolic Ca2+ or that temporarily inactivate SERCA did not alter any of the above parameters. Cells expressing a TG-resistant form of SERCA progressed normally through the G1/S transition after TG treatment. These results suggest that long-term SERCA inactivation affects cell cycle-dependent events and compromises progression through G1/S.

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Calcium Calcium-Transporting ATPases Cell Line Cyclin D1 Cyclin E G1 Phase Humans Mitogen-Activated Protein Kinases S Phase Sarcoplasmic Reticulum Calcium-Transporting ATPases Thapsigargin Journal Article Research Support, Non-U.S. Gov't

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V R Simon, M F Moran. 2001. SERCA activity is required for timely progression through G1/S.. https://doi.org/10.1046/j.1365-2184.2001.00192.x

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