Assessing Glucose Uptake in the Motor Neurons of Drosophila Larvae with Upregulated Glucose Metabolism

Place control and mutant Drosophila larvae into separate dishes containing a glucose-free buffer.

Dissect the larvae to remove internal organs, exposing the central nervous system or CNS.

The CNS includes a ventral nerve cord harboring motor neurons. In the mutant larvae, these neurons exhibit upregulated glucose metabolism.

Motor neurons in both groups express intracellular glucose sensors containing donor and acceptor fluorophores.

Position the larvae under a confocal microscope. Upon excitation, the donor fluorophore emits fluorescence.

Locate the motor neurons using this fluorescence.

Replace the buffer with a glucose-supplemented solution.

Glucose enters the neurons, binding to the sensors and triggering a conformational change that brings the two fluorophores into proximity.

Upon excitation, the acceptor absorbs the donor-emitted energy, termed fluorescence resonance energy transfer or FRET, and emits fluorescence.

The FRET signal correlates with glucose uptake. A higher acceptor signal intensity in the mutant larvae compared to the control indicates upregulated glucose metabolism.

Before beginning the dissections, turn on the imaging microscope and lasers. Then, collect a wa