We discuss adifferential geometry based multiscale and multiphysics paradigm for ion channel systems. We describe macromolecular systems by a number of approaches, including macroscopic electrostatics and elasticity and/or microscopic molecular mechanics (MM) and quantum mechanics; while treating the aqueous environment as a dielectric continuum or electrolytic fluids. We use differential geometry theory of surfaces to couple various microscopic and macroscopic domains on an equal footing. Based on the variational principle, we derive the coupled Poisson-Boltzmann, Nernst-Planck, Kohn-Sham, Laplace-Beltrami, and Newton equations for the structure, function, dynamics and transport of ion-channel systems. We employ homology modeling to construct mosquito sodium channels and combine MM and PNP type of approaches for the understanding of sodium channel gating.