The genome sequence of the bed bug, Cimex lectularius, is described in two separate papers published in Nature Communications this week. Together, the studies provide insights into the genetic basis of how this parasite has adapted to feeding on blood and highlight genes that may be associated with insecticide resistance.
The bed bug is a parasite that feeds on blood and has been associated with humans for thousands of years. Global infestations of bed bugs have been associated with the rise of heated homes and international travel, and this problem has been exacerbated by the evolution of insecticide resistance in bed bugs over the past 20 years.
In the first paper, Jeffrey Rosenfeld and colleagues sequence and assemble the genome of the bed bug and identify all genes expressed during the five immature stages, as well as in adult males and females. They show that the greatest degree of change in which genes are expressed by the bed bug takes place when it feeds on blood for the first time. They also compare bed bug DNA collected from subway stations across the city of New York and find that bed bugs tend to be more closely related to other bed bugs from the same borough.
In a related paper, Joshua Benoit and colleagues sequence and assemble the genome of the bed bug, predict which sequences code for proteins, and describe the biological function of those proteins. They identify 187 potential genes encoding blood digestive enzymes and an expanded array of salivary proteins that allow bedbugs to feed repeatedly on the same host without inflicting pain. They also identify genes associated with insecticide resistance, including proteins in the animals’ cuticle that can impede insecticide penetration, and enzymes that can detoxify insecticides.