In Drosophila QUIVER (also known as SLEEPLESS protein or SSS) is a (GPI)-anchored protein required for homoeostatic regulation of sleep under normal conditions and following sleep deprivation [1]. It is a novel potassium channel subunit that modulates the Shaker (Sh) potassium channel which regulates the sleep [2,3]. Besides the Sh modulation, SSS also antagonises nicotinic acetylcholine receptors (nAChRs) to reduce synaptic transmission and promote sleep [4].

1: Identification of SLEEPLESS, a sleep-promoting factor. Koh K, Joiner WJ, Wu MN, Yue Z, Smith CJ, Sehgal A; Science. 2008;321:372-376. PMID:18635795

2: Drosophila QVR/SSS modulates the activation and C-type inactivation kinetics of Shaker K(+) channels. Dean T, Xu R, Joiner W, Sehgal A, Hoshi T; J Neurosci. 2011;31:11387-11395. PMID:21813698

3: SLEEPLESS, a Ly-6/neurotoxin family member, regulates the levels, localization and activity of Shaker. Wu MN, Joiner WJ, Dean T, Yue Z, Smith CJ, Chen D, Hoshi T, Sehgal A, Koh K; Nat Neurosci. 2010;13:69-75. PMID:20010822

4: SLEEPLESS is a bifunctional regulator of excitability and cholinergic synaptic transmission. Wu M, Robinson JE, Joiner WJ; Curr Biol. 2014;24:621-629. PMID:24613312