Chromosomal localization and chemosensory expression profile of Tribolium CSPs and OBPs. (A) Chromosomal localization of CSPs (magenta), classic OBPs (black), ABPII (grey), C-OBPs (green) and C + OBP (blue), based on Georgia GA-2 strain genome assembly 3.0 . The arrowheads indicate the orientation of the genes from 5′►3′. Genes encoding for more than the six highly conserved cysteines (or four in case of C-OBP) are labeled with an asterisk (*). (B) Heatmap showing the absolute expression level of the OBPs/CSPs as log2 (RPKM + 1) in different tissues (adult antennae, head (missing antennae but including mouth parts), mouthparts, legs, body, as well as larval head and body). The candidates are blotted according to their chromosomal localization, horizontal brackets above indicate clustering in the genome. A black dot in the first row labeled ‘MALDI’ indicates that at least one unique tryptic fragment of the particular candidate was identified in an antennae sample on protein level. The expression levels are represented by a log2 greyscale with high expression levels (216 RPKM) labelled black. The asterisks mark statistically significant differtially expressed genes compared to body. The red asterisks represent up- and the blue down-regulation (p-values are * < 0.05; ** < 0.01; *** < 0.001).