Figure 7.

erification of mature vitellogenin protein in the head fat body cells of a nurse bee worker (a, 5 × magnification, see inserted box for the fat cells depicted as close ups at 40 × magnification, b-c). The fat body cells are located in the vicinity of the brood food producing hypopharyngeal glands and thereby close to the brain (a, asterisk). Numerous vitellogenin positive granules are localized in the cells (b, b', see arrow in b). Corresponding controls were treated with preimmune sera and show no positive staining c, c'). Dark field (b') shows positive staining as bright white dots, whereas the corresponding control (c') is negative for vitellogenin.