tetracycline and Feminization

Brevipalpus californicus (Banks) was infected with 'Candidatus Cardinium' bacteria (Cardinium). Tetracycline-treated females produced many male progeny even though untreated females produced only female progeny. B. californicus appears to be feminized by Cardinium. The values for net reproduction rate (R0), generation time (T) and intrinsic rate of natural increase (r(m)) calculated for B. californicus were 7.48/day, 31.45 days and 0.064/day, respectively. The comparison of infected females with uninfected males and other closely related species, indicated that Cardinium does not have a negative effect on the fitness of B. californicus.

Topics: Animals; Anti-Bacterial Agents; Bacteroidetes; Base Sequence; DNA, Bacterial; Female; Feminization; Male; Mites; Parthenogenesis; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sequence Alignment; Sequence Analysis, DNA; Tetracycline

Wolbachia are symbiotic bacteria found in many arthropods and filarian nematodes. They often manipulate the reproduction of host arthropods. In the present study, female-biased sex-ratio distortion in the butterfly Eurema hecabe was investigated. Breeding experiments showed that this distorted sex ratio is maternally inherited. When treated with tetracycline, adult females of the thelygenic line produced male progeny only. After PCR using Wolbachia-specific primers for the ftsZ gene a positive result was seen in the thelygenic females, but not in male progeny from tetracycline-treated females, or individuals from a Tokyo population with normal sex ratio and reproduction. Cytological observations showed that thelygenic females lack the sex chromatin body (W chromosome). The results strongly suggest that the sex-ratio distortion in E. hecabe is due to feminization of genetic males by Wolbachia.

Topics: Animals; Bacterial Proteins; Butterflies; Cytoskeletal Proteins; Female; Feminization; Larva; Male; Oviposition; Reproduction; Rickettsiaceae; Sex Ratio; Symbiosis; Tetracycline