Publications by authors named "Caline Karam"

Cloud computing allows storing the ever-growing genotype-phenotype datasets crucial for precision medicine. Due to the sensitive nature of this data and varied laws and regulations, additional security measures are needed to ensure data privacy. We develop SQUiD, a secure queryable database for storing and analyzing genotype-phenotype data.

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Cloud computing provides the opportunity to store the ever-growing genotype-phenotype data sets needed to achieve the full potential of precision medicine. However, due to the sensitive nature of this data and the patchwork of data privacy laws across states and countries, additional security protections are proving necessary to ensure data privacy and security. Here we present SQUiD, a ecure eryable atabase for storing and analyzing genotype-phenotype data.

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Abuse of psychostimulants, including amphetamines (AMPHs), is a major public health problem with profound psychiatric, medical, and psychosocial complications. The actions of these drugs at the dopamine transporter (DAT) play a critical role in their therapeutic efficacy as well as their liability for abuse and dependence. To date, however, the mechanisms that mediate these actions are not well-understood, and therapeutic interventions for AMPH abuse have been limited.

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The dopamine transporter (DAT) mediates the inactivation of released dopamine (DA) through its reuptake, and thereby plays an important homeostatic role in dopaminergic neurotransmission. Amphetamines exert their stimulant effects by targeting DAT and inducing the reverse transport of DA, leading to a dramatic increase of extracellular DA. Animal models have proven critical to investigating the molecular and cellular mechanisms underlying transporter function and its modulation by psychostimulants such as amphetamine.

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Article Synopsis
  • Circadian clocks synchronize various bodily functions into daily rhythms, but neurodegenerative diseases like Alzheimer's disrupt these rhythms, sleep patterns, and cognitive abilities, though the reasons for this are still unclear.
  • Researchers explored how the tau protein affects neuronal circadian biology, utilizing a tau-deficient model to show that losing tau leads to disrupted circadian rhythms and sleep.
  • The absence of tau alters the structural plasticity of key circadian neurons and affects core clock protein levels, indicating that tau plays a crucial role in maintaining the functionality and connectivity of circadian networks.
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Dopamine (DA) receptors play critical roles in a wide range of behaviours, including sensory processing, motor function, reward and arousal. As such, aberrant DA signalling is associated with numerous neurological and psychiatric disorders. Therefore, understanding the mechanisms by which DA neurotransmission drives intracellular signalling pathways that modulate behaviour can provide critical insights to guide the development of targeted therapeutics.

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Amphetamines (AMPHs) are potent psychostimulants that are widely used and abused, with profound medical and societal impact. Their actions at dopaminergic neurons are thought to mediate their therapeutic efficacy as well as their liability for abuse and dependence. AMPHs target the dopamine transporter (DAT), the plasmalemmal membrane protein that mediates the inactivation of released dopamine (DA) through its reuptake.

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The ability of presynaptic dopamine terminals to tune neurotransmitter release to meet the demands of neuronal activity is critical to neurotransmission. Although vesicle content has been assumed to be static, in vitro data increasingly suggest that cell activity modulates vesicle content. Here, we use a coordinated genetic, pharmacological, and imaging approach in Drosophila to study the presynaptic machinery responsible for these vesicular processes in vivo.

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The dopamine transporter (DAT), which mediates the inactivation of released dopamine through its reuptake, is the primary molecular target for the actions of psychostimulants. An increasing number of studies support an essential role for phosphorylation of serines (Ser) in the distal amino (N) terminus of DAT in regulating its function. Still, the molecular details of the regulation of phosphorylation and its impact on function are not fully understood.

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Amphetamines elevate extracellular dopamine, but the underlying mechanisms remain uncertain. Here we show in rodents that acute pharmacological inhibition of the vesicular monoamine transporter (VMAT) blocks amphetamine-induced locomotion and self-administration without impacting cocaine-induced behaviours. To study VMAT's role in mediating amphetamine action in dopamine neurons, we have used novel genetic, pharmacological and optical approaches in Drosophila melanogaster.

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Dopamine D(2) receptor antagonism is a unifying property of all antipsychotic drugs in use for schizophrenia. While often effective at ameliorating psychosis, these drugs are largely ineffective at treating negative and cognitive symptoms. Increasing attention is being focused on the complex genetics of the illness and the signaling pathways implicated in its pathophysiology.

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Post-translational modifications of histone proteins modulate the binding of transcription regulators to chromatin. Studies in Drosophila have shown that the phosphorylation of histone H3 at Ser10 (H3S10ph) by JIL-1 is required specifically during early transcription elongation. 14-3-3 proteins bind H3 only when phosphorylated, providing mechanistic insights into the role of H3S10ph in transcription.

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The Drosophila JIL-1 kinase is known to phosphorylate histone H3 at Ser10 (H3S10) during interphase. This modification is associated with transcriptional activation, but its function is not well understood. Here we present evidence suggesting that JIl-1-mediated H3S10 phosphorylation is dependent on chromatin remodeling by the brahma complex and is required during early transcription elongation to release RNA polymerase II (Pol II) from promoter-proximal pausing.

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