FIGURE 3.

Two ORs from group II are specifically expressed in sensilla trichodea. Cells expressing distinct OR types as well as Orco or SNMP1 were visualized by means of two-color FISH using specific antisense riboprobes labeled in either DIG (OR, red fluorescence) or Bio (Orco and SNMP1, green fluorescence). (A–D) The expression of OR102 and OR111 in cells housed in sensilla trichodea is visualized. As indicated in A (OR102) and in C (OR111) labeled cells are located under trichoid (Tr) sensillar hairs. In panel B,D co-localization of the two trichoid OR types with Orco are depicted. Discernable basiconic sensilla (Ba) and trichoid sensilla (Tr) cell clusters are indicated by white dash circles and white boxes (B,D), respectively. The insets panel B’–D” depict the separate fluorescence channels of panels B,D. The white dash circle highlights the cell that concomitantly expresses the defined OR type and Orco. (E,F) The co-expression of OR102 and OR111 with SNMP1 is documented. In the insects panels E’–F” the separate fluorescence channels of the white boxed areas in panels E,F are depicted. The double labeled areas are indicated by white dash circles. Scale bars, 10 μm.