RRC ID 507
Author Banno Y, Nakamura T, Nagashima E, Fujii H, Doira H.
Title M chromosome of the wild silkworm, Bombyx mandarina (n = 27), corresponds to two chromosomes in the domesticated silkworm, Bombyx mori (n = 28).
Journal Genome
Abstract Chromosomes of Bombyx mori (n = 28) and of Bombyx mandarina (n = 27) were studied cytogenetically to resolve the origin of the large M chromosome in the Japaneses type of B. mandarina. In the F1 progeny from the reciprocal cross between B. mandarina and B. mori, the mitotic chromosome number was 2n = 55, and a chromosome configuration of 26 bivalents plus 1 trivalent was observed at metaphase I of germ cells. The trivalent chromosome consisted of the M chromosome from B. mandarina and two chromosomes from B. mori. When males of B. mori were mated to the F1 females, nuclei with two types of chromosome number (2n = 55 and 2n = 56) and two sets of chromosome pairs (26 bivalents plus 1 trivalent versus 28 bivalents) were observed in the metaphase I stage. Linkage analysis showed that the 14th chromosome of B. mori was involved in these two types of chromosome segregation. This result indicates that the M chromosome in B. mandarina arose from a fusion between a chromosome corresponding to the 14th linkage group and another, yet unidentified linkage group.
Volume 47(1)
Pages 96-101
Published 2004-2
DOI 10.1139/g03-112
PII g03-112
PMID 15060606
MeSH Animals Bombyx / genetics* Chromosome Mapping Chromosome Segregation / genetics* Chromosomes / genetics* Crosses, Genetic Japan Karyotyping
IF 1.892
Times Cited 15
Silkworms B. mori strains