Fig. 5.

Components of the visual and olfactory systems are highly rhythmic. (A) Twelve genes in the Drosophila visual signaling transduction pathway were identified as rhythmic in LD and or/DD heads. Positions of rhythmic genes within the visual signaling transduction pathway are shown. Peak phase under LD and DD conditions is indicated in red next to gene names as Zeitgeber time (ZT) and circadian time (CT). Blue type indicates subcomponents of the visual transduction pathway. The Drosophila ortholog to the eye-specific G protein β-subunit gene gbe (AGAP001506) was found to be rhythmic in DD conditions only. *Note that Drosophila ortholog to the eye-specific diacylglycerol kinase gene retinal degeneration A (rdgA) (AGAP000519) is included in the pathway despite having a mean normalized fluorescence expression level <20. The signaling pathway was adapted from the Drosophila pathway described by Zuker (84) and Katz and Minke (85) and is assumed to be similar in Anopheles (123). Many of these genes continue to be rhythmic in DD conditions (Dataset S1), revealing that visual transduction is under circadian clock control. Gene identification was predicted from the highest percent similarity An. gambiae ortholog. M, active metarhodopsin; R, rhodopsin; PI, phosphatidylinositol; DAG-CDP, cytidine diphosphate diacylglycerol; PIP, phosphatidylinositol phosphate; PA, phosphatidic acid. (Inset) Transcription profiles of selected rhythmic vision genes under LD conditions. Expression values are normalized to the median value across the time course of each gene. Day and night are indicated by the horizontal white/black bar below the chart. (B) Hierarchical clustering of rhythmic olfaction genes under LD conditions in the head. Red indicates higher expression, and green indicates lower expression versus the mean value for each gene. Day and night are indicated by the horizontal white/black bar above the heatmap. A majority of the OBPs are expressed in synchrony, with a peak phase at ∼ZT12.