Detection of Neural Activity in the Brains of Japanese Honeybee Workers during the Formation of a “Hot Defensive Bee Ball”
(A) Schematic diagram of the lateral view of a bee brain. Areas colored in light orange indicate neuropil regions. D, dorsal; V, ventral; R, rostral; C, caudal. MB, mushroom bodies; AL, antennal lobes; and SOG, subesophageal ganglion. The green line indicates the position of sections analyzed in this experiment. (B) A schematic diagram of a middle right brain hemisphere of the Japanese worker honeybee. Areas colored in light grey indicate brain areas where the somata of neurons are located. Red squares correspond to brain areas whose in situ hybridization results are presented below. M, medial; L, lateral. OL, optic lobe; DL, dorsal lobe. (C–N) Expression analysis of Acks by in situ hybridization using coronal brain sections of seizure-induced (Sz-induced) (C–H) or control Japanese honeybee workers (I–N). The upper panels (C and I), middle panels (E and K), and lower panels (G and M) correspond to MB, OL, and area between the DL and OL, which are boxed in (B). Bars indicate 100 µm. (D, F, H, J, L, and N) Magnified views of the regions delineated by dotted lines in panels (C), (E), (G), (I), (K), and (M), respectively. Yellow arrowheads indicate Acks signals. Bars indicate 10 µm.