Fig. 6: A pair of NPFR-expressing enteric neurons senses NPF secreted from EECs and inhibits feeding.

a Food intake of NPFR heterozygous control (NPFR⁸/+ and NPFR^null/+) and NPFR mutant (NPFR⁸ and NPFR^null) flies. b NPFR staining (green) in EECs of control and tap^1.3-B-Gal4 > NPFR^RNAi flies. 30 midguts each were examined. c Food intake of control and tap^1.3-B-Gal4 > NPFR^RNAi flies. d The GFP expression pattern driven by NPFR^RA/C-Gal4 in CNS (1), enteric neurons in the hypocerebral ganglion (HCG) (2), midgut circular muscle (3) and longitudinal muscle (4), EECs (5) and neuronal projection to the hindgut (6) and rectal ampulla (7). 25 flies were examined. e GFP expression pattern driven by GMR60E02 (NPFR^ENS)-Gal4. White dashed box frames the cell body of a pair of enteric neurons, with magnified view shown in the lower right corner. AKH staining (red) indicates the location of the corpora cardiaca. The enhanced GFP channel (white) is shown on the right. 31 flies were examined. f Food intake of flies with NPFR knockdown in NPFR^ENS neurons or elimination of this pair of neurons ( > hid). g Food intake of flies with the indicated genotypes. Note that inhibition of NPFR^ENS neurons ( > shi^ts, 30 °C) promoted feeding, whereas exciting NPFR^ENS neurons ( > TrpA1, 30 ^oC) inhibited food intake. h, i Upon indicated manipulations, representative images h and quantification i of relative CaLexA intensity in NPFR^ENS neurons. j, k Food intake of flies with the indicated genotypes under 1% L-Glu feeding condition. NPFR knockdown in NPFR^ENS neurons j or inhibition of NPFR^ENS neuron function (k, >shi^ts, 30 °C) had a similar food intake as control in PBS injection group, whereas NPFR knockdown j or inhibition of NPFR^ENS neurons k had a higher food consumption than control in NPF injection group. l Under 1% L-Glu feeding condition, activation of NPFR^ENS neurons ( > TrpA1, 30 ^oC) inhibited food intake. Data are represented as mean ± SD. Significance was determined using two-sided unpaired t-test a, c, f, g, i–l. n, number of groups performed for quantification of food intake (5 flies in each group) a, c, f, g, j–l, or the number of NPFR^ENS-Gal4⁺ cells i. Source data are provided as a Source Data file. Scale bars, 20 μm unless otherwise specified.