Conserved synteny of genes between chromosome 15 of Bombyx mori and a chromosome of Manduca sexta shown by five-color BAC-FISH.
The successful assignment of the existing genetic linkage groups (LGs) to individual chromosomes and the second-generation linkage map obtained by mapping a large number of bacterial artificial chromosome (BAC) contigs in the silkworm, Bombyx mori, together with public nucleotide sequence databases, offer a powerful tool for the study of synteny between karyotypes of B. mori and other lepidopteran species. Conserved synteny of genes between particular chromosomes can be identified by comparatively mapping orthologous genes of the corresponding linkage groups with the help of BAC-FISH (fluorescent in situ hybridization). This technique was established in B. mori for 2 differently labeled BAC probes simultaneously hybridized to pachytene bivalents. To achieve higher-throughput comparative mapping using BAC-FISH in Lepidoptera, we developed a protocol for five-color BAC-FISH, which allowed us to map simultaneously 6 different BAC probes to chromosome 15 in B. mori. We identified orthologs of 6 B. mori LG15 genes (RpP0, RpS8, eIF3, RpL7A, RpS23, and Hsc70) for the tobacco hornworm, Manduca sexta, and selected the ortholog-containing BAC clones from an M. sexta BAC library. All 6 M. sexta BAC clones hybridized to a single M. sexta bivalent in pachytene spermatocytes. Thus, we have confirmed the conserved synteny between the B. mori chromosome 15 and the corresponding M. sexta chromosome (hence provisionally termed chromosome 15).
Laboratory of Applied Molecular Entomology, Research Institute of Agriculture, Hokkaido University, N9, W9, Kita-ku, Sapporo 060-8589, Japan. sahara@abs.agr.hokudai.ac.jp
Ken
K
Sahara
Atsuo
A
Yoshido
Frantisek
F
Marec
Iva
I
Fuková
Hong-Bin
HB
Zhang
Cheng-Cang
CC
Wu
Marian R
MR
Goldsmith
Yuji
Y
Yasukochi
D000818:Animals; D012831:Bombyx; D002874:Chromosome Mapping; D002875:Chromosomes; D022202:Chromosomes, Artificial, Bacterial; D008040:Genetic Linkage; D005821:Genetic Techniques; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D007915:Lepidoptera; D018402:Manduca; D008856:Microscopy, Fluorescence; D013045:Species Specificity; D026801:Synteny