Biology subjects

Foster, R. G.

Publications and source records attributed to Foster, R. G..

3 recordsLinked to original sources

bioRxiv2020

Fluorescent in vivo editing reporter (FIVER): A novel multispectral reporter of in vivo genome editing

Advances in genome editing technologies have created opportunities to treat rare genetic diseases, which are often overlooked in terms of therapeutic development. Nonetheless, substantial challenges remain: namely, achieving therapeutically beneficial levels and kinds of editing in the right cell type(s). Here we describe the development of FIVER (fluorescent in vivo editing reporter) -- a modular toolkit for in vivo detection of genome editing with distinct fluorescent read-outs for non-homologous end-joining (NHEJ), homology-directed repair (HDR) and homology-independent targeted integration (HITI). We demonstrate that fluorescent outcomes reliably report genetic changes following editing with diverse genome editors in primary cells, organoids and in vivo. We show the potential of FIVER for high-throughput unbiased screens, from small molecule modulators of genome editing outcomes in primary cells through to genome-wide in vivo CRISPR cancer screens. Importantly, we demonstrate its in vivo application in postnatal organ systems of interest for genetic therapies -- retina and liver. FIVER will broadly help expedite the development of therapeutic genome surgery for many genetic disorders.

genetics↗

bioRxiv2020

The role of the hypothalamus in cortical arousaland sleep homeostasis

Sleep and wakefulness are not simple homogenous all-or-none states, but instead are characterized by rich dynamics of brain activity across many temporal and spatial scales. Rapid global state transitions between waking and sleeping are believed to be controlled by hypothalamic circuits, but the contribution of the hypothalamus to within-state changes of sleep and wake "intensity" remains largely unexplored. Here we show that stimulation of inhibitory neurons in the preoptic hypothalamus does not merely trigger awakening from sleep, but the resulting awake state is also characterized by increased cortical activity. This activation is associated with a faster build-up of sleep pressure, proportional to the arousal level. These findings show that hypothalamic systems thought to exclusively control global state switching, also regulate within-state "intensity", which we propose as a key intrinsic variable in shaping the architecture of sleep/wake states across the 24h day.

neuroscience↗

bioRxiv2020

The relationship between fasting-induced torpor,sleep and wakefulness in the laboratory mouse

Torpor is a regulated reversible state of metabolic suppression used by many mammalian species to conserve energy. Although torpor has been studied extensively in terms of general physiology, metabolism and neuroendocrinology, the effects of hypometabolism and associated hypothermia on brain activity and states of vigilance have received little attention. Here we performed continuous monitoring of electroencephalogram (EEG), electromyogram (EMG) and peripheral body temperature in adult, male C57BL/6 mice over consecutive days of scheduled restricted feeding. All animals showed prominent bouts of hypothermia that became progressively deeper and longer as fasting progressed. EEG and EMG were markedly affected by hypothermia, although the typical electrophysiological signatures of NREM sleep, REM sleep and wakefulness allowed us to perform vigilance-state classification in all cases. Invariably, hypothermia bouts were initiated from a state indistinguishable from NREM sleep, with EEG power decreasing gradually in parallel with decreasing body temperature. Furthermore, during deep hypothermia REM sleep was largely abolished, but we observed brief and intense bursts of muscle activity, which resembled the regular motor discharges seen during early ontogeny associated with immature sleep patterns. We conclude that torpor and sleep are electrophysiologically on a continuum, and that, in order for torpor to occur, mice need to first transition through euthermic sleep.

neuroscience↗