Skip to main content
. 2022 Dec 6;11:e80859. doi: 10.7554/eLife.80859

Figure 5. Longer mbCHCs are associated with higher desiccation resistance.

(A) Quantity of 2MeC26 is negatively correlated with desiccation resistance in males, but no correlation in females (Females: p = 0.1, Males: r = −0.4, p < 0.001). (B) Quantity of 2MeC28 is positively correlated with desiccation resistance (Females: r = 0.4, p < 0.001, Males: r = 0.4, p < 0.001). (C) Quantity of 2MeC30 is positively correlated with desiccation resistance in females, but no correlation in males (Females: r = 0.2, p = 0.009, Males: p = 0.2). (D) Quantity of 2MeC32 is positively correlated with desiccation resistance (Females: r = 0.3, p < 0.001, Males: r = 0.4, p < 0.001). Correlations between the quantities of each mbCHC and desiccation resistance were determined using Pearson’s method. (E) D. melanogaster coated with longer mbCHCs have higher desiccation resistance. Coating of synthetic mbCHCs on D. melanogaster showed that 2MeC26 does not influence desiccation resistance. 2MeC30 increases desiccation resistance in female D. melanogaster while both 2MeC28 and 2MeC30 in increases desiccation resistance in male D. melanogaster. The bold horizontal line within each box plot corresponds to the median value, the box length to the interquartile range, and the lines emanating from the box (whiskers) extend to the smallest and largest observations. One-way analysis of variance (ANOVA) showed significant differences between D. melanogaster flies coated with different mbCHCs (Female: F(3,189) = 73.1, p < 0.001, Male: F(3,191) = 23.7, p < 0.001). Post hoc comparison was conducted using Tukey’s method. ***p < 0.001; n.s. refers to not significant.

Figure 5—source data 1. Desiccation resistance of Drosophila melanogaster attP40 flies when coated with individual mbCHC of 2MeC26, 2MeC28, and 2MeC30.
Figure 5—source data 2. Desiccation resistance of Drosophila melanogaster attP40 flies when coated with individual n-alkane of C23, C25, C27, C29, and C31.
Figure 5—source data 3. Desiccation resistance of Drosophila melanogaster CHC- flies when coated with individual CHC of 2MeC26, 2MeC28, 2MeC30, C23, C25, C27, C29, and C31.

Figure 5.

Figure 5—figure supplement 1. Correlation between different mbCHCs in 50 Drosophila and related species.

Figure 5—figure supplement 1.

Correlation between different mbCHCs was determined using Pearson’s method. Significant correlations between each pairs of mbCHCs were labeled with stars following with the correlation coefficients. The lines on the diagonals represent the distribution of the data for each mbCHC. **p < 0.01; ***p < 0.001.
Figure 5—figure supplement 2. The length of coated mbCHCs on D. melanogaster attP40 flies is positively correlated with desiccation resistance in both females and males.

Figure 5—figure supplement 2.

Pearson’s correlation: Female, r = 0.7, p < 0.001; Male, r = 0.5, p < 0.001.
Figure 5—figure supplement 3. Desiccation resistance of D. melanogaster attP40 flies coated with individual n-alkanes (C23, C25, C27, C29, and C31).

Figure 5—figure supplement 3.

One-way analysis of variance (ANOVA) was applied to test the differences in desiccation resistance between the coating of different n-alkanes (Female: F(5, 277) = 17.1, p < 0.001, Male: F(5, 287) = 8.0, p < 0.001), following with post hoc comparison using Tukey’s method at alpha = 0.05. *p < 0.05; **p < 0.01; ***p < 0.001; n.s. refers to not significant. The bold horizontal line within each box plot corresponds to the median value, the box length to the interquartile range, and the lines emanating from the box (whiskers) extend to the smallest and largest observations. Numbers on top of the boxplots are the mean in each treatment.
Figure 5—figure supplement 4. The length of coated n-alkanes on D. melanogaster attP40 flies is positively correlated with desiccation resistance in both females and males.

Figure 5—figure supplement 4.

Pearson’s correlation: Female, r = 0.4, p < 0.001; Male, r = 0.1, p = 0.02.
Figure 5—figure supplement 5. Desiccation resistance of CHC- D. melanogaster flies coated with individual mbCHCs (2MeC26, 2MeC28, 2MeC30) or n-alkanes (C23, C25, C27, C29, and C31).

Figure 5—figure supplement 5.

One-way analysis of variance (ANOVA) was applied to test the difference of desiccation resistance between the coating of different mbCHCs and n-alkanes (Female: F(8, 417) = 11.2, p < 0.001, Male: F(8, 408) = 7.1, p < 0.001), following with post hoc comparison using Tukey’s method at alpha = 0.05. *p < 0.05; **p < 0.01; ***p < 0.001. The bold horizontal line within each box plot corresponds to the median value, the box length to the interquartile range, and the lines emanating from the box (whiskers) extend to the smallest and largest observations. Numbers on top of the boxplots are the mean in each treatment.
Figure 5—figure supplement 6. The length of coated mbCHCs on CHC- flies has a weak positive correlation with desiccation resistance in females but did not correlate with the levels of desiccation resistance in males.

Figure 5—figure supplement 6.

Pearson’s correlation: Female, r = 0.2, p = 0.004; Male, p = 0.9.
Figure 5—figure supplement 7. The length of coated n-alkanes on CHC- flies did not correlate with desiccation resistance.

Figure 5—figure supplement 7.

Pearson’s correlation: Female, p = 0.4; Male, p = 1.0.
Figure 5—figure supplement 8. Pathway for the synthesis of branched cuticular hydrocarbons (mbCHCs) and linear CHCs (n-alkanes, monoenes, and dienes).

Figure 5—figure supplement 8.

All CHCs are synthesized via the fatty acyl-CoA synthesis pathway from acetyl-CoA. The pathway splits early due to the action of two fatty acid synthetases (FAS) into the branched CHC pathway or the linear CHC pathway. The precursors of each pathway are modified by synthesis enzymes such as elongases (Elo), reductases (FAR), and the terminal P450 decarbonylase (CYP4G) into CHCs. For linear CHCs, additional enzymes such as desaturases (Desat) incorporate double bonds during synthesis. The diagram was modified from Chung and Carroll, 2015.
Figure 5—figure supplement 9. Gas chromatography–mass spectrometry (GC–MS) chromatograms of 5′mFAS-GAL4, UAS-Cyp4g1-RNAi, and the F1 offspring from 5′mFAS-GAL4 × UAS-Cyp4g1-RNAi.

Figure 5—figure supplement 9.

CHC- D. melanogaster flies are generated by crossing 5′mFAS-GAL4 and UAS-Cyp4g1-RNAi, resulting in adult oenocyte specific knockdown of Cyp4g1 and loss of cuticular hydrocarbon (CHC) production. IS = internal standard spiked in for quantification (C26). cVA = cis-vaccenyl acetate, a lipid produced in the male ejaculatory bulb not affected by the RNAi knockdown of Cyp4g1 in the oenocytes.