title: Sperm-less males modulate female behaviour in Ceratitis capitata (Diptera: Tephritidae).
abstract: In the Mediterranean fruit fly, Ceratitis capitata (Wiedemann)(Diptera: Tephritidae), mating has a strong impact on female biology, leading to a decrease in sexual receptivity and increased oviposition and fecundity. Previous studies suggest that sperm transfer may play a role in inducing these behavioural changes. Here we report the identification of a medfly innexin gene, Cc-inx5, whose expression is limited to the germ-line of both sexes. Through RNA interference of this gene, we generated males without testes and, consequently, sperm, but apparently retaining all the other reproductive organs intact. These sperm-less males were able to mate and, like their wild-type counterparts, to induce in their partners increased oviposition rates and refractoriness to remating. Interestingly, matings to sperm-less males results in oviposition rates higher than those induced by copulation with control males. In addition, the observed female post-mating behavioural changes were congruent with changes in transcript abundance of genes known to be regulated by mating in this species. Our results suggest that sperm transfer is not necessary to reduce female sexual receptivity and to increase oviposition and fecundity. These data pave the way to a better understanding of the role/s of seminal components in modulating female post-mating responses. In the long term, this knowledge will be the basis for the development of novel approaches for the manipulation of female fertility, and, consequently, innovative tools to be applied to medfly control strategies in the field.
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Gabrieli
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Scolari
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Di Cosimo
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Grazia
authors.initials: G
authors.lastname: Savini
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Fumagalli
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Ludvik M
authors.initials: LM
authors.lastname: Gomulski
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy.
authors.forename: Anna R
authors.initials: AR
authors.lastname: Malacrida
authors.affiliation: Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy. Electronic address: gasperi@unipv.it.
authors.forename: Giuliano
authors.initials: G
authors.lastname: Gasperi
mesh_terms: D000818:Animals; D033622:Ceratitis capitata / Q000235:genetics / Q000502:physiology*; D005260:Female; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008297:Male; D010802:Phylogeny; D034622:RNA Interference; D020539:Sequence Analysis, Protein; D012726:Sexual Behavior, Animal; D013094:Spermatozoa / Q000166:cytology
chemical_list: D019476:Insect Proteins
keywords: Ceratitis capitata; Innexin; Post-mating behaviour; RNA interference; Seminal fluid; Sperm