Calmodulin protects cells from death under normal growth conditions and mitogenic starvation but plays a mediating role in cell death upon B-cell receptor stimulation

TY - JOUR

T1 - Calmodulin protects cells from death under normal growth conditions and mitogenic starvation but plays a mediating role in cell death upon B-cell receptor stimulation

AU - Schmalzigaug, R

AU - Ye, Q

AU - Berchtold, M W

N1 - Keywords: Animals; Apoptosis; Calcium; Calmodulin; Cell Cycle; Cell Division; Chickens; Gene Deletion; Phosphorylation; Protein-Tyrosine Kinases; RNA, Messenger; Receptors, Antigen, B-Cell; Signal Transduction; Tumor Cells, Cultured

PY - 2001

Y1 - 2001

N2 - Calmodulin (CaM) is the main intracellular Ca2+ sensor protein responsible for mediating Ca2+ triggered processes. Chicken DT40 lymphoma B cells express CaM from the two genes, CaMI and CaMII. Here we report the phenotypes of DT40 cells with the CaMII gene knocked out. The disruption of the CaMII gene causes the intracellular CaM level to decrease by 60%. CaMII-/- cells grow more slowly and die more frequently as compared to wild type (wt) cells but do not exhibit significant differences in their cell cycle profile. Both phenotypes are more pronounced at reduced serum concentrations. Upon stimulation of the B-cell receptor (BCR), the resting Ca2+ levels remain elevated after the initial transient in CaMII-/- cells. Despite higher Ca2+ resting levels, the CaMII-/- cells are partially protected from BCR induced apoptosis indicating that CaM plays a dual role in apoptotic processes.

AB - Calmodulin (CaM) is the main intracellular Ca2+ sensor protein responsible for mediating Ca2+ triggered processes. Chicken DT40 lymphoma B cells express CaM from the two genes, CaMI and CaMII. Here we report the phenotypes of DT40 cells with the CaMII gene knocked out. The disruption of the CaMII gene causes the intracellular CaM level to decrease by 60%. CaMII-/- cells grow more slowly and die more frequently as compared to wild type (wt) cells but do not exhibit significant differences in their cell cycle profile. Both phenotypes are more pronounced at reduced serum concentrations. Upon stimulation of the B-cell receptor (BCR), the resting Ca2+ levels remain elevated after the initial transient in CaMII-/- cells. Despite higher Ca2+ resting levels, the CaMII-/- cells are partially protected from BCR induced apoptosis indicating that CaM plays a dual role in apoptotic processes.

M3 - Journal article

C2 - 11454062

SN - 0019-2805

VL - 103

SP - 332

EP - 342

JO - Immunology

JF - Immunology

IS - 3

ER -