Plays a role in promoting sleep by enhancing metabotropic transmission of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in GABAergic neurons upstream of a wake-inducing dopaminergic pathway. Detected primarily at presynaptic sites on axons, and to a lesser degree in soma and dendrites. Not detected at post-synaptic sites. Expressed in both anterior and posterior regions of the brain including in GABAergic neurons. Belongs to the rogdi family. Truncated C-terminus.