Thermosensitive alternative splicing senses and mediates temperature adaptation in < i > Drosophila < /i >

Circadian rhythms are generated by cyclic transcription, translation, and degradation of clock gene products, includingtimeless(tim), but how the circadian clock senses and adapts to temperature changes is not completely understood. Here we show that temperature dramatically changes the splicing pattern oftim inDrosophila. We found that at 18 °C, TIM levels are low due to the induction of two cold-specific isoforms:tim-cold andtim-short&cold. At 29 °C, another isoform,tim-medium, is upregulated. This isoform switching regulates the levels and activity of TIM as each isoform has a specific function. We found thattim-short&cold encodes a protein that rescues the behavioral defects oftim01mutants and that flies in whichtim-short&coldis abrogated have abnormal locomotor activity. In addition, miRNA-mediated control limits the expression of some of these isoforms. Finally, our data using minigenes suggest thattimalternative splicing might act as a thermometer for the circadian clock.
Source: eLife - Category: Biomedical Science Tags: Neuroscience Source Type: research