Regulatory subunit of Kv4/D (Shal)-type voltage-gated rapidly inactivating A-type potassium channels, such as KCND2/Kv4.2 and KCND3/Kv4.3 (PubMed:19109250). Modulates channel expression at the cell membrane, gating characteristics, inactivation kinetics and rate of recovery from inactivation in a calcium-dependent and isoform-specific manner. Component of heteromultimeric potassium channels (PubMed:19713751, PubMed:20943905). Identified in potassium channel complexes containing KCND1, KCND2, KCND3, KCNIP1, KCNIP2, KCNIP3, KCNIP4, DPP6 and DPP10 (PubMed:19713751). Interacts with the C-terminus of PSEN2 and probably PSEN1 (By similarity). Interacts with KCND2 and KCND3. Expressed in brain. Highly expressed by neurons in layers II-IV of cortex and in hippocampus, thalamus and the Purkinje cell layer of the cerebellum. The KIS (K-channel inactivation suppressor) domain is required for converting A-type Kv4 current to a slowly inactivating delayed rectifier potassium current. Belongs to the recoverin family.