Fragile X mental retardation protein controls gating of the sodium-activated potassium channel Slack

Abstract

Fragile X mental retardation protein (FMRP) binds to RNA and interacts with other ribonucleoproteins. Here, the authors describe both an interaction between FMRP and the sodium-activated potassium channel Slack-B and the FMRP regulation of Slack channel kinetics. In humans, the absence of Fragile X mental retardation protein (FMRP), an RNA-binding protein, results in Fragile X syndrome, the most common inherited form of intellectual disability. Using biochemical and electrophysiological studies, we found that FMRP binds to the C terminus of the Slack sodium-activated potassium channel to activate the channel in mice. Our findings suggest that Slack activity provides a link between patterns of neuronal firing and changes in protein translation.