Insect Epigenetic Mechanisms Facing Anthropogenic-Derived Contamination, an Overview

Abstract

Currently, the human species has been recognized as the primary species responsible for Earth’s biodiversity decline. Contamination by different chemical compounds, such as pesticides, is among the main causes of population decreases and species extinction. Insects are key for ecosystem maintenance; unfortunately, their populations are being drastically affected by human-derived disturbances. Pesticides, applied in agricultural and urban environments, are capable of polluting soil and water sources, reaching non-target organisms (native and introduced). Pesticides alter insect’s development, physiology, and inheritance. Recently, a link between pesticide effects on insects and their epigenetic molecular mechanisms (EMMs) has been demonstrated. EMMs are capable of regulating gene expression without modifying genetic sequences, resulting in the expression of different stress responses as well as compensatory mechanisms. In this work, we review the main anthropogenic contaminants capable of affecting insect biology and of triggering EMMs. EMMs are involved in the development of several diseases in native insects affected by pesticides (e.g., anomalous teratogenic reactions). Additionally, EMMs also may allow for the survival of some species (mainly pests) under contamination-derived habitats; this may lead to biodiversity decline and further biotic homogenization. We illustrate these patterns by reviewing the effect of neonicotinoid insecticides, insect EMMs, and their ecological consequences.

Reproductive Potential Impacts Body Maintenance Parameters and Global DNA Methylation in Honeybee Workers (Apis mellifera L.)

“…Moreover, the level of global DNA methylation in normal workers in our study is similar as in the publications by Strachecka et al [19,20,49,50], Paleolog et al [18], Schulz et al [51]. Biostimulants and herbs reduce the level of global DNA methylation, while pesticides, acaricides, and other anthropogenic factors increase it at a certain age stage of bees [18][19][20]49,[52][53][54]. In other organisms, i.e., Osmia rufa [55], Varroa destructor [56], human [57,58], the level of global DNA methylation is much higher than in A. mellifera workers.…”

Interaction of Insecticides and Fungicides in Bees

“…Most investigations study lethal doses and mortality, while sublethal effects are insufficiently studied. Closing these knowledge gaps is urgent, because these factors most likely have a large share in the decline of bees and other pollinators (25)(26)(27)(28).…”

Heritable Epigenomic Modifications Influence Stress Resilience and Rapid Adaptations in the Brown Planthopper (Nilaparvata lugens)

“…Further, it has been speculated that EMMs, in several phytophagous insects, contribute to their resilience to various environmental stresses posed by pesticides, temperature, etc. [ 17 , 18 ]. However, we believe that in addition to providing resistance/tolerance capacity to various abiotic stresses, they can also help insects overcome host plant resistance.…”