NPF-Driven Gart Expression Fuels Gut Absorption and Modulates Feeding via a Negative Feedback Loop

Area of Science:

• Neuroscience
• Metabolism
• Molecular Biology

Background:

• Energy homeostasis relies on integrating brain signals with peripheral nutrient handling.
• Neuropeptide F (NPF) and NPY are known central feeding stimulators, but their role in gut nutrient assimilation is unclear.

Purpose of the Study:

• To investigate the role of NPF in regulating nutrient assimilation in the gut.
• To identify molecular mechanisms linking NPF signaling to gut function and energy balance.

Main Methods:

• Utilized *Drosophila* as a model organism.
• Investigated the transcriptional circuit between NPF and the GART enzyme.
• Employed genetic epistasis experiments to determine the functional relationship between NPF and GART.

Main Results:

• Identified a reciprocal regulatory loop where NPF signaling upregulates gut GART expression, enhancing nutrient absorption.
• Demonstrated that gut-specific GART is necessary and sufficient for promoting food absorption and consumption.
• Showed that peripheral NPF, not brain-derived NPF, is the primary signal in this gut-centered homeostatic module.

Conclusions:

• NPF acts as a key regulator of peripheral metabolic efficiency by activating GART to boost nutrient absorption.
• Established a novel framework for understanding gut-brain communication in energy balance.
• Redefined NPF's role from a behavioral driver to a regulator of nutrient assimilation.