A Virtual Data Repository Stimulates Data Sharing in a Consortium.

Research data may have substantial impact beyond the original study objectives. The Collaborating Consortium of Cohorts Producing NIDA Opportunities (C3PNO) facilitates the combination of data and access to specimens from nine NIDA-funded cohorts in a virtual data repository (VDR). Unique challenges were addressed to create the VDR.

Adult circadian behavior in Drosophila requires developmental expression of cycle, but not period.

Circadian clocks have evolved as internal time keeping mechanisms that allow anticipation of daily environmental changes and organization of a daily program of physiological and behavioral rhythms. To better examine the mechanisms underlying circadian clocks in animals and to ask whether clock gene expression and function during development affected subsequent daily time keeping in the adult, we used the genetic tools available in Drosophila to conditionally manipulate the function of the CYCLE component of the positive regulator CLOCK/CYCLE (CLK/CYC) or its negative feedback inhibitor PERIOD (PER). Differential manipulation of clock function during development and in adulthood indicated that there is no developmental requirement for either a running clock mechanism or expression of per.

Fluorescence/luminescence circadian imaging of complex tissues at single-cell resolution.

The use of luciferase reporter genes together with luminescence detection has enabled high frequency monitoring of molecular circadian clock function in living tissues. With the help of an intensified CCD camera combined with an inverted epifluorescence microscope, the authors have established a new imaging strategy that makes use of transgenic cell type-specific expression of fluorescent proteins to identify cells of interest for subsequent circadian luminescence recording at single-cell resolution.

Selective entrainment of the Drosophila circadian clock to daily gradients in environmental temperature.

Background: Circadian clocks are internal daily time keeping mechanisms that allow organisms to anticipate daily changes in their environment and to organize their behavior and physiology in a coherent schedule. Although circadian clocks use temperature compensation mechanisms to maintain the same pace over a range of temperatures, they are also capable of synchronizing to daily temperature cycles. This study identifies key properties of this process.