Pharmacological characterization of the neuropeptide F receptor (NPFR) in Macrobrachium rosenbergii

The neuropeptide F receptor (NPFR) is a critical regulator of energy homeostasis in invertebrates, orchestrating feeding behavior, nutrient assimilation, and reproductive functions. We report the successful cloning and functional characterization of NPFR from the giant freshwater prawn Macrobrachium rosenbergii. Structural analysis confirmed that the cloned sequence is a typical GPCR with seven transmembrane domains and conserved motifs DRY and NPLLY. Sequence alignment showed high homology (>90 %) with other long-arm shrimp species, supporting evolutionary conservation within the Palaemonidae family. Quantitative real-time PCR (qRT-PCR) revealed ubiquitous expression of mrNPFR, with the highest levels in the intestinal tract, followed by hemolymph and eyestalk ganglia, suggesting multifunctional roles in energy homeostasis and neuroendocrine regulation. Functional assays using luciferase reporter systems demonstrated that NPF-II was the most potent cAMP inhibitor, while NPF-III exhibited the highest efficacy in activating the MAPK/ERK pathway. NPF-I showed the highest activation efficacy for the NFAT pathway. This study provides foundational data for understanding NPFR’s physiological functions in M. rosenbergii and offers insights for precision feeding strategies in aquaculture.