Male-Specific Transfer and Fine Scale Spatial Differences of Newly Identified Cuticular Hydrocarbons and Triacylglycerides in a Drosophila Species Pair

Abstract

We analyzed epicuticular hydrocarbon variation in geographically isolated populations of D. mojavensis cultured on different rearing substrates and a sibling species, D. arizonae, with ultraviolet laser desorption/ionization mass spectrometry (UV-LDI MS). Different body parts, i.e. legs, proboscis, and abdomens, of both species showed qualitatively similar hydrocarbon profiles consisting mainly of long-chain monoenes, dienes, trienes, and tetraenes. However, D. arizonae had higher amounts of most hydrocarbons than D. mojavensis and females of both species exhibited greater hydrocarbon amounts than males. Hydrocarbon profiles of D. mojavensis populations were significantly influenced by sex and rearing substrates, and differed between body parts. Lab food–reared flies had lower amounts of most hydrocarbons than flies reared on fermenting cactus substrates. We discovered 48 male- and species-specific hydrocarbons ranging in size from C22 to C50 in the male anogenital region of both species, most not described before. These included several oxygen-containing hydrocarbons in addition to high intensity signals corresponding to putative triacylglycerides, amounts of which were influenced by larval rearing substrates. Some of these compounds were transferred to female cuticles in high amounts during copulation. This is the first study showing that triacylglycerides may be a separate class of courtship-related signaling molecules in drosophilids. This study also extends the kind and number of epicuticular hydrocarbons in these species and emphasizes the role of larval ecology in influencing amounts of these compounds, many of which mediate courtship success within and between species.

Aging modulates cuticular hydrocarbons and sexual attractiveness inDrosophila melanogaster

“…LDI-MS more efficiently detects polar CHC (e.g. oxygen-containing compounds), many of which are not detected by GC/MS (supplementary material Fig.S2) (Yew et al, 2009), as well as particular long-chained hydrocarbons (Yew et al, 2011a), but it does not detect alkanes. Because only intact molecular ions are detected and thus no structural information is obtained, the stereochemistry of a compound cannot be elucidated.…”

“…We closely followed the method outlined by Yew and colleagues (Yew et al, 2009;Yew et al, 2011b) for detecting CHC by LDI-MS. To account for biological variability, quantitative data were derived by averaging the signal intensities obtained from 3-5 individual flies for each age and genotype. Flies were anesthetized and mounted with fine forceps onto adhesive tape (G304, Plano GmbH, Wetzlar, Germany), which was attached to a glass coverslip.…”

Deciphering the signature of cuticular lipids with contact sex pheromone function in a parasitic wasp

“…However, it has been unclear whether they are actually present on the epicuticle or merely co-extracted from the fat body or other internal tissues (Buckner, 1993). Recent studies using ultraviolet laser desorption/ionization mass spectrometry demonstrated the presence of TAGs on the cuticle of Drosophila flies (Yew et al, 2011), but a communicative function has never been shown so far.…”

Direct Laser Desorption Ionization of Endogenous and Exogenous Compounds from Insect Cuticles: Practical and Methodologic Aspects

“…In addition, pheromones have been manipulated in order to control the population growth of agricultural pests and disease-bearing insects [2]. Recently, we showed that ultraviolet laser desorption ionization orthogonal time-of-flight mass spectrometry (UV-LDI o-TOF MS) allows analysis of cuticular hydrocarbons and triglycerides directly from the external cuticle of individual fruit flies [3][4][5]. Direct UV-LDI MS provides spatially-resolved analysis of HCs without chemical extraction or the addition of a matrix to the cuticle.…”