May play a role in action potential conduction in myelinated cells through the organization of molecular complexes at nodes of Ranvier and axon initial segments (PubMed:25953347, PubMed:25950943, PubMed:27979964). May also play a role in axon outgrowth and guidance (PubMed:25953347). Homooligomer (via coiled coil domain) (PubMed:27979964). Interacts (via IQ domain) with calmodulin; the interaction is direct and lost in presence of calcium (PubMed:18550753). Interacts with ANK3 (via ANK repeats); required for its localization at axon initial segments (AIS) and nodes of Ranvier (PubMed:18550753). Interacts with SPTBN4 (PubMed:27979964). Interacts with KCNQ2 and KCNQ3 (PubMed:27979964). Localizes to the axon initial segments (AIS) and nodes of Ranvier of neurons and is absent from dendrites. Mice lacking all isoforms encoded by both Schip1 and Iqcj-Schip1 are fertile and survive as long as wild-type mice. However, they exhibit mild growth delay associated with ataxia and reduced pain sensitivity. They display decreased thickness of the piriform cortex and partial agenesis of the anterior comissure which could be due to impaired axon elongation and guidance. The morphology of nodes of Ranvier is affected but nerves do not exhibit significant electrophysiological characteristic differences. A reduction in the number of axonal projections in the peripheral nerve system is also observed. Based on a naturally occurring readthrough transcript which produces an IQCJ-SCHIP1 fusion protein. Based on a naturally occurring readthrough transcript which produces an IQCJ-SCHIP1 fusion protein.