CACNB2, also known as Calcium Channel Voltage-Dependent Beta 2 Subunit, is a protein that plays a crucial role in the functioning of voltage-gated calcium channels (VGCCs). These channels control calcium entry into cells in response to changes in membrane potential, affecting essential processes such as neurotransmitter release, muscle contraction, and gene expression. CACNB2 primarily acts as a regulatory subunit of VGCCs, interacting with the pore-forming alpha subunits to regulate their voltage sensitivity, channel opening and closing dynamics, and calcium conductance.