MACRAE and ANDERSON observed a large frequency change of mitochondrial DNA (mtDNA) haplotypes in a population initiated with two allopatric strains of Drosophila pseudoobscura, BogER from Colombia and AH162 from California. They concluded that mtDNA haplotypes in D. pseudoobscura are not always selectively neutral. NIGRO and PROUT suggested, however, that a maternally transmitted incompatibilit...

Intracellular symbionts are present in a wide variety of animals, plants and other life forms (Correa and Ballard, 2016); and have an intriguing lifestyle. To enhance their spread, intracellular symbionts have evolved a variety of mechanisms. Some of them provide benefits to their host and are effectively mutualists (e.g., Buchnera in aphids; Douglas, 1998), while others bias the sex ratio of t...

Bacteria of the genus Wolbachia are among the most common endosymbionts in the world. In many insect species these bacteria induce a sperm-egg incompatibility between the gametes of infected males and uninfected females, commonly called unidirectional cytoplasmic incompatibility (CI). It is generally believed that unidirectional CI cannot promote speciation in hosts because infection difference...

In a recent Current Biology paper [1], we reported that pheromone communication occurred during metamorphosis in Drosophila melanogaster. Female pheromones appeared to influence various aspects of the physiology and development of adult males. In particular, we observed that this communication regulated testis development and had a positive impact on reproduction, as measured by a difference in...

Manipulation of host reproduction and efficient maternal transmission have facilitated the global spread of Wolbachia through millions of insect species. Cytological studies of the most common Wolbachia-induced phenotype, cytoplasmic incompatibility (CI), demonstrate that Wolbachia induce CI by altering host cell cycle timing. Cytological analyses also suggest that microtubules and motor protei...

Cytoplasmically (maternally) inherited bacteria that cause reproductive incompatibility between strains are widespread among insects. In the parasitoid wasp Nasonia, incompatibility results in improper condensation and fragmentation of the paternal chromosomes in fertilized eggs. Some form of genome imprinting may be involved. Because of haplodiploidy, incompatibility results in conversion of (...

In Drosophila melanogaster, weak incompatibility in crosses between infected and uninfected strains is associated with a Wolbachia microorganism. Crosses between infected males and uninfected females show a reduction (15-30%) in egg hatch. Progeny tests indicated that the infection is widespread in Australian D. melanogaster populations and that populations are polymorphic for the presence of t...

In Drosophila simulans a Wolbachia-like microorganism is responsible for reduced egg-hatch when infected males mate with uninfected females. Both incompatibility types have previously been found in North America, Europe and Africa. Some California populations have remained polymorphic for over two years, and the infection is apparently spreading in central California. Egg hatch proportions for ...

Releasing Wolbachia-infected mosquitoes to suppress or replace wild vector has been carried out in 24 countries worldwide, showing great promise controlling and mosquito-borne diseases. To face the instability of Wolbachia infection different environments during area-wide application, we should consider overlapping two strains. In this case, bidirectional cytoplasmic incompatibility occurs, whi...

Wolbachia species are endosymbionts of a wide range of invertebrates, including mosquitoes, fruit flies, and nematodes. The wPip strains can cause cytoplasmic incompatibility in some strains of the Culex mosquito. Here we describe the genome sequence of a Wolbachia strain that was discovered in the whole-genome sequencing data for the mosquito Culex quinquefasciatus strain JHB.