Calcium channels play important roles in cellular signalling. TRP (transient receptor potential) channels form a superfamily of calcium channels through which Ca 2+ enters the cell. TRPs have six transmembrane segments with a putative pore between the fifth and the sixth segments, and assemble in tetrameric complexes to form functional Ca 2+ channels. They are thus similar to K V (voltage-gated potassium channel) channels in terms of structure and molecular determinants that promote subunit assembly. In this review, the molecular determinants mediating the assembly of Drosophila TRP, TRPC (TRP canonical), TRPV (TRP vanilloid) and K V channels are described.