Related Experiment Video
Updated: May 31, 2026

Applying an Inducible Expression System to Study Interference of Bacterial Virulence Factors with Intracellular Signaling
Published on: June 25, 2015
Negative regulation of NaF-induced apoptosis by Bad-CAII complex
S Otsuki1, K Sugiyama, O Amano
1Division of Pharmacology, Meikai University School of Dentistry, Sakado, Saitama 350-0283, Japan.
Abstract:
Fluoride is used to prevent caries in dentistry. However, its mechanism of cytotoxicity induction is unclear. This study was undertaken to determine whether sodium fluoride (NaF) induces apoptosis in human oral cells and if so, whether Bad protein is involved in the process. NaF showed higher cytotoxicity and apoptosis-inducing activity against human oral squamous cell carcinoma cells (HSC-2) than against human gingival fibroblasts (HGF). Western blot analysis showed that NaF enhanced the expression and dephosphorylation of Bad protein. This study demonstrates for the first time that Bad protein forms a complex with carbonic anhydrase II (CAII), and NaF stimulates the detachment of CAII from the Bad-CAII complex and the replacement by the formation of Bad-Bcl-2 complex. Knockdown of Bad and CAII mRNA by siRNA inhibited and enhanced the NaF-induced caspase activation, respectively. The present study suggests that CAII negatively regulates the NaF-induced apoptosis by forming a complex with Bad.
Related Concept Videos
The Intrinsic Apoptotic Pathway
Caspases
The Extrinsic Apoptotic Pathway
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
Necrosis
Morphological Manifestations of Necrosis
Necrotic cells show different types of morphological appearance depending on the type of tissue and infection. In coagulative necrosis, cells become anucleated and die, but their...
Calmodulin-dependent Signaling
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
