Detecting proliferation of adult hemocytes in Drosophila by BrdU incorporation

Drosophila and mammalian hematopoiesis share several similarities that ranges from phases to the battery of transcription factors and signaling molecules that execute this process. These resounding similarities along with the rich genetic tools available in fruitfly makes it a popular invertebrate model to study blood cell development both during normal and aberrant conditions. The larval system is the most extensively studied to date. Several studies have shown that these hemocytes just like mammalian counterpart proliferate and get routinely regenerated upon infection. However, employing the same protocol it was concluded that blood cell proliferation although abundant in larval stages is absent in adult fruitfly. The current protocol describes the strategies that can be employed to document the hemocyte proliferation in adulthood. The fact that a subset of blood cells tucked away in the hematopoietic hub are not locked in senescence, rather they still harbour the proliferative capacity to tide over challenges was successfully demonstrated by this method.  Although we have adopted bacterial infection as a bait to evoke this proliferative capacity of the hemocytes, we envision that it can also efficiently characterize the proliferative responses of hemocytes in tumorigenic conditions as well as scenarios of environmental and metabolic stresses during adulthood.

Effects of dichlorobenzene, toluene, benzene and formaldehyde chemicals on Drosophila melanogaster mortality

Environmental exposures to volatile organic compound (VOC) mixtures have received increasing attention, yet the risks are under studied. This study aimed to explore the risks of combined exposures to several commonly detected VOCs and to draw attention to the necessity of studying long-term and low-concentration environmental exposure patterns. In this study, we examined the effects of long-term and low-concentration exposures to VOCs like 1,2-dichlorobenzene, benzene, toluene and formaldehyde either alone or in combination on D. melanogaster mortality. A quantitative relationship was established between 1,2-dichlorobenzene concentration and mortality. Additionally, 1,2-dichlorobenzene was more toxic than toluene, and males were more sensitive to 1,2-dichlorobenzene. In cocktail, 1,2-dichlorobenzene + benzene, 1,2-dichlorobenzene acted as an antagonist and interaction type may depend on component concentration. Antagonistic interaction was also found in twice mixture of toluene + benzene + formaldehyde and the degree of antagonism decreased with increasing concentrations of formaldehyde + benzene. The observed interactions and variations in their type or degree relative to mixture component concentrations may be attributed to inter-component metabolic interference and metabolic saturation.