Opsin transcripts in the cricket compound eye detected by antisense riboprobes. (AC) Dorso-ventral sections through the adult retina taken at similar depths: greenB is transcribed in all eye regions except for the DRA; uv is found in the DRA (arrowhead) and in the remainder of the eye excluding a horizontal band in the ventral half (arrow); blue transcription is confined to the DRA and a ventral band. (DE) Oblique cross-sections through the dorsal-(D) and ventral (E) retina. All distal receptors in the DRA and some in the ventral retina transcribe blue. The asterisk denotes the growth zone of the larval eye. (F) Oblique cross-section-(G) quasi-longitudinal section through the ventral retina. uv is transcribed in small, proximal receptors in the DRA (arrowhead). Next to the DRA and ventral to the ventral band, uv can be found at more distal levels (arrows) than in the central retina. (H) Longitudinal section showing a typical greenB staining, which is stronger distally than proximally. (I) Distal cross-section and (JK) longitudinal sections through the central retina. All four receptors around the crystalline cone (as outlined by a circle) transcribe greenB. At the level of weaker greenB staining (J), the uv staining begins (K). Up corresponds to dorsal in (AC, EH), frontal in (D), medial in (I) and distal in (JK). Sections (D, HI), (AB, JK) and (C, EG) from larvae, adult females and adult males, respectively. Broken lines in histological sections denote the basement membrane and scale bars indicate 100 μm. (L) Schematic longitudinal sections through ommatidia in the DRA and central retina with cross-sections at indicated levels-Illustration modified after [45,46,76]. C cornea, CC crystalline cone. Colors denote opsin mRNA expression deduced from (CD) and (F, HK).
Henze et al. BMC Evolutionary Biology 2012 12:163 doi:10.1186/1471-2148-12-163