title: Meiotic Recombination Analyses in Pigs Carrying Different Balanced Structural Chromosomal Rearrangements.
abstract: Correct pairing, synapsis and recombination between homologous chromosomes are essential for normal meiosis. All these events are strongly regulated, and our knowledge of the mechanisms involved in this regulation is increasing rapidly. Chromosomal rearrangements are known to disturb these processes. In the present paper, synapsis and recombination (number and distribution of MLH1 foci) were studied in three boars (Sus scrofa domestica) carrying different chromosomal rearrangements. One (T34he) was heterozygote for the t(3;4)(p1.3;q1.5) reciprocal translocation, one (T34ho) was homozygote for that translocation, while the third (T34Inv) was heterozygote for both the translocation and a pericentric inversion inv(4)(p1.4;q2.3). All three boars were normal for synapsis and sperm production. This particular situation allowed us to rigorously study the impact of rearrangements on recombination. Overall, the rearrangements induced only minor modifications of the number of MLH1 foci (per spermatocyte or per chromosome) and of the length of synaptonemal complexes for chromosomes 3 and 4. The distribution of MLH1 foci in T34he was comparable to that of the controls. Conversely, the distributions of MLH1 foci on chromosome 4 were strongly modified in boar T34Inv (lack of crossover in the heterosynaptic region of the quadrivalent, and crossover displaced to the chromosome extremities), and also in boar T34ho (two recombination peaks on the q-arms compared with one of higher magnitude in the controls). Analyses of boars T34he and T34Inv showed that the interference was propagated through the breakpoints. A different result was obtained for boar T34ho, in which the breakpoints (transition between SSC3 and SSC4 chromatin on the bivalents) seemed to alter the transmission of the interference signal. Our results suggest that the number of crossovers and crossover interference could be regulated by partially different mechanisms.
authors.affiliation: INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mary
authors.affiliation: Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.
authors.forename: Harmonie
authors.initials: H
authors.lastname: Barasc
authors.affiliation: UE1372 GenESI Génétique, Expérimentation et Système Innovants, Surgères, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Ferchaud
authors.affiliation: UE1372 GenESI Génétique, Expérimentation et Système Innovants, Surgères, France.
authors.forename: Aurélia
authors.initials: A
authors.lastname: Priet
authors.affiliation: Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Calgaro
authors.affiliation: INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Loustau-Dudez
authors.affiliation: Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Bonnet
authors.affiliation: INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.
authors.forename: Martine
authors.initials: M
authors.lastname: Yerle
authors.affiliation: Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Ducos
authors.affiliation: INRA, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENSAT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Castanet-Tolosan, France.|Université de Toulouse INPT ENVT, UMR1388 Génétique, Physiologie et Systèmes d'Elevage, Toulouse, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Pinton
mesh_terms: D000818:Animals; D007446:Chromosome Inversion / Q000235:genetics* / Q000662:veterinary*; D023902:Chromosome Pairing / Q000502:physiology*; D003434:Crossing Over, Genetic / Q000235:genetics; D053903:DNA Breaks, Double-Stranded; D004260:DNA Repair / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008540:Meiosis / Q000235:genetics*; D000070957:MutL Protein Homolog 1 / Q000235:genetics*; D012854:Sister Chromatid Exchange / Q000235:genetics; D034421:Sus scrofa / Q000235:genetics*; D013552:Swine; D014178:Translocation, Genetic / Q000235:genetics*
chemical_list: D000070957:MutL Protein Homolog 1