Fam148b Activators

Chemical activators of C2 calcium dependent domain containing 4B (C2CD4B) encompass a variety of compounds that influence intracellular calcium levels, a key regulator for the activation of this protein. Calcium chloride directly contributes to the activation of C2CD4B by increasing the concentration of calcium ions within the cell. Similarly, ionophores like ionmycin and calcimycin facilitate the influx of calcium ions into the cytosol from the extracellular space or intracellular stores, thereby providing the necessary calcium ions to activate C2CD4B. Thapsigargin serves this role by a different mechanism; it inhibits the sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA), leading to a buildup of cytosolic calcium that, in turn, activates C2CD4B.

Furthermore, compounds that modulate calcium channels or signaling pathways indirectly influence the activation state of C2CD4B. Phorbol 12-myristate 13-acetate (PMA) and 1,2-Dioctanoyl-sn-glycerol (DiC8) activate protein kinase C (PKC), which is known to enhance downstream calcium-dependent processes, including those involving C2CD4B. BAY K 8644 and its more specific enantiomer, (S)-(-)-Bay K 8644, act as L-type calcium channel agonists, boosting calcium entry into the cell, which aids in the activation of C2CD4B. Nitrendipine, by blocking these channels, paradoxically can also lead to increased intracellular calcium that activates C2CD4B. Another modulator, FPL 64176, enhances calcium influx through its action on calcium channels, thereby promoting C2CD4B activation. Lastly, cyclopiazonic acid and ryanodine disrupt calcium regulation within the cell by inhibiting the SERCA pump and modifying ryanodine receptor function, respectively; both result in elevated cytosolic calcium levels that facilitate C2CD4B activation.