Identification of novel split-GAL4 drivers for the characterization of enteroendocrine cells in the Drosophila melanogaster midgut

Abstract

The Drosophila melanogaster midgut is commonly studied as a model epithelial tissue for many reasons, one of which is the presence of a diverse population of secretory cells called enteroendocrine cells. Subpopulations of these cells secrete various combinations of peptide hormones which have systemic effects on the organism. Many of these hormones are also produced in the Drosophila brain. The split-GAL4 system has been useful for identifying and manipulating discrete groups of cells, but previously characterized split-GAL4 drivers have not driven expression in high proportions of enteroendocrine cells. In this study, we screened candidate split-GAL4 drivers for enteroendocrine cell expression using known reference drivers for this cell type and discovered a new split-GAL4 driver pair that confers expression in a greater number of enteroendocrine cells than previously characterized driver pairs. The new pair demonstrates less brain expression, thereby providing better tools for disentangling the physiological roles of gut- and brain-secreted peptides. We also identified additional split-GAL4 drivers that promote expression in discrete subpopulations of enteroendocrine cells. Overall, the tools reported here will help researchers better target enteroendocrine cell subpopulations.

Whole organism snRNA-seq reveals systemic peripheral changes in Alzheimer’s Disease fly models

“…Note that pan-neuronal drivers, including elav-GAL4 and nSyb-GAL4 , are expressed at low levels in EEs (Holsopple et al, 2022a, 2022b; Katheder et al, 2023), consistent with our findings that nSyb transcripts are at lower levels in EEs than neurons (fig. S19A).…”

Nicotinic acetylcholine receptor signaling maintains epithelial barrier integrity

“… ( A ) Split Gal4 approach to identify enteroendocrine cell (EE)-specific drivers without neuronal expression: BL91402 is an EE reference stock expressing EGFP used by Holsopple et al, 2022 ; Hu et al, 2011 , that expresses the p65 activation domain (AD) in EEs under control of sequences in/near Dh31. Crossed to its DBD counterpart, it labels pros-positive EEs with GFP (green), but also enterocytes (ECs) (pink arrowheads) and displays neuronal expression (yellow arrowheads).…”

split-intein Gal4 provides intersectional genetic labeling that is fully repressible by Gal80

“…amino acids 2-93), split intein GeneSwitch constructs were generated using as the splice junction the same C 21 cysteine residue. The split intein Gal4 and split intein GeneSwitch constructs thus share the same N-terminal Gal4 [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] component.…”