Nuclear Transcriptomes of the Seven Neuronal Cell Types That Constitute the Drosophila Mushroom Bodies

“…Notably, we find that nAChRα3 ∩ fru P1 expression is absent from the mushroom body in both sexes, whereas we observe mushroom body expression for all other nAChR s ∩ fru P1 examined ( Figure 9D–S ). We also find that nAChRα3 is not a marker gene in mushroom body clusters identified in our data sets ( Source data 3 ), consistent with previous reports indicating its absence from the mushroom body ( Croset et al, 2018 ; Shih et al, 2019 ). Our expression findings here, and the identification of several nAChR s in genomic studies examining regulation by Fru M , expression in fru P1 neurons, and expression changes post-mating, suggest that nAChR s are important for Drosophila reproductive behaviors ( Brovkina et al, 2021 ; Dalton et al, 2013 ; Neville et al, 2014 ; Newell et al, 2016 ; Newell et al, 2020 ; Palmateer et al, 2021 ; Vernes, 2014 ).…”

“…For this purpose, we chose to use MB247-Gal4 as this line was shown to drive expression in ⍺/ß p,s,c -type KCs and ɣ d,main- type KCs, while no expression is visible in ⍺’/ß’-type KC ( 46 ). This fits RNA-seq data showing that DH31R expression is detectable mainly in ⍺/ß p,c -type KCs ( 17 ). Compared to genetic controls, MB247>DH31R-RNAi flies showed significantly increased learning in the evening (ZT9-11; Fig.4A).…”

“…Where neuron counts were different for a given hemisphere, the average was plotted. Numbers of γ d neurons in wild-type animals were intermediate between those reported in prior studies ( Aso et al, 2014a ; Shih et al, 2019 ), while numbers of α´/β´ and α/β c neurons were lower, likely reflecting conservative assignment of nuclei in our study and the use of different antibodies and reporters ( Aso et al, 2014a ; Shih et al, 2019 ). α´/β´ counts obtained using the MB370B driver were similar to previously reported numbers of α´/β´ m neurons; because MB370B labels α´/β´ m neurons strongly and α´/β´ ap neurons weakly, the lower absolute numbers of α´/β´ neurons in our studies may reflect detection sensitivity and correspond chiefly to α´/β´ m neurons.…”