Roles of dopamine in circadian rhythmicity and extreme light sensitivity of circadian entrainment.

Light has profound behavioral effects on almost all animals, and nocturnal animals show sensitivity to extremely low light levels [1-4]. Crepuscular, i.e.

AKT-sensitive or insensitive pathways of toxicity in glial cells and neurons in Drosophila models of Huntington's disease.

Huntington's disease (HD) is caused by an extended polyglutamine (polyQ) tract in the Huntingtin protein. Neuronal and glial dysfunction precedes the neurodegeneration and appears to be the primary cause for the early symptoms in HD. In recent years, development of Drosophila models of polyQ-related diseases facilitated research of candidate rescuer genes.

Physiological requirement for the glutamate transporter dEAAT1 at the adult Drosophila neuromuscular junction.

L-glutamate is the major excitatory neurotransmitter in the mammalian brain. Specific proteins, the Na+/K+-dependent high affinity excitatory amino acid transporters (EAATs), are involved in the extracellular clearance and recycling of this amino acid. Type I synapses of the Drosophila neuromuscular junction (NMJ) similarly use L-glutamate as an excitatory transmitter.

Expanded polyglutamine peptides disrupt EGF receptor signaling and glutamate transporter expression in Drosophila.

Huntington's disease (HD) is a late onset heritable neurodegenerative disorder caused by expansion of a polyglutamine (polyQ) sequence in the protein huntingtin (Htt). Transgenic models in mice have suggested that the motor and cognitive deficits associated to this disease are triggered by extended neuronal and possibly glial dysfunction, whereas neuronal death occurs late and selectively. Here, we provide in vivo evidence that expanded polyQ peptides antagonize epidermal growth factor receptor (EGFR) signaling in Drosophila glia.

Decreasing glutamate buffering capacity triggers oxidative stress and neuropil degeneration in the Drosophila brain.

L-glutamate is both the major brain excitatory neurotransmitter and a potent neurotoxin in mammals. Glutamate excitotoxicity is partly responsible for cerebral traumas evoked by ischemia and has been implicated in several neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). In contrast, very little is known about the function or potential toxicity of glutamate in the insect brain.

Tissue-specific developmental requirements of Drosophila tyrosine hydroxylase isoforms.

Drosophila tyrosine hydroxylase (DTH) is a key enzyme in dopamine (DA) biosynthesis, which is expressed in neural and hypodermal DA-synthesizing cells. We previously reported that two DTH isoforms are produced in flies through tissue-specific alternative splicing that show distinct regulatory properties. We have now selectively expressed each DTH isoform in vivo in a pale (ple, i.

Tissue-specific developmental requirements of Drosophila tyrosine hydroxylase isoforms.

Drosophila tyrosine hydroxylase (DTH) is a key enzyme in dopamine (DA) biosynthesis, which is expressed in neural and hypodermal DA-synthesizing cells. We previously reported that two DTH isoforms are produced in flies through tissue-specific alternative splicing that show distinct regulatory properties. We have now selectively expressed each DTH isoform in vivo in a pale (ple, i.