Interaction of annexin A3 with Cav3.1 T-type calcium channels.

摘要

A specific isoform of the Cav3.1 T-type calcium channel, ac, is present in glioma, but not in other cells of the human CNS. The variable region of this Cav3.1 ac isoform associates with the annexin A3 molecule while the other isoforms (a, b, bc) do not, indicating this interaction may have implications in the tumorgenicity of glial tumours. Annexin A3 was found to be expressed in the tsA-201 cells used for Ca v3.1 ac electrophysiological recording. Over expression of annexin A3 or blocking the interaction of annexin A3 with the Cav3.1 ac channel with peptide sequences both produced no change in Cav3.1 gating properties. The U251N glioma cell line was characterized as an appropriate study system as it contained mRNA for the Cav3.1 ac variant, expressed Cav3.1, and expressed annexin A3. Finally, ideal transfection conditions utilizing lipofectamine 2000 were determined for future studies.