| RRC ID |
3494
|
| Author |
Abe H, Fujii T, Tanaka N, Yokoyama T, Kakehashi H, Ajimura M, Mita K, Banno Y, Yasukochi Y, Oshiki T, Nenoi M, Ishikawa T, Shimada T.
|
| Title |
Identification of the female-determining region of the W chromosome in Bombyx mori.
|
| Journal |
Genetica
|
| Abstract |
The W chromosome of the silkworm Bombyx mori is devoid of functional genes, except for the putative female-determining gene (Fem). To localize Fem, we investigated the presence of W-specific DNA markers on strains in which an autosomal fragment containing dominant marker genes was attached to the W chromosome. We produced new W-chromosomal fragments from the existing Zebra-W strain (T(W;3)Ze chromosome) by X-irradiation, and then carried out deletion mapping of these and sex-limited yellow cocoon strains (T(W;2)Y-Chu, -Abe and -Ban types) from different Japanese stock centers. Of 12 RAPD markers identified in the normal W chromosomes of most silkworm strains in Japan, the newly irradiated W(B-YL-YS)Ze chromosome contained three, the T(W;2)Y-Chu chromosome contained six, and the T(W;2)Y-Abe and -Ban chromosomes contained only one (W-Rikishi). To investigate the ability of the reduced W-chromosome translocation fragments to form heterochromatin bodies, which are found in nuclei of normal adult female sucking stomachs, we examined cells of the normal type p50 strain and the T(W;2)Y-Chu and -Abe strains. A single sex heterochromatin body was found in nuclei of p50 females, whereas we detected only small sex heterochromatin bodies in the T(W;2)Y-Chu strain and no sex heterochromatin body in the T(W;2)Y-Abe strain. Since adult females of all strains were normal and fertile, we conclude that only extremely limited region, containing the W-Rikishi RAPD sequence of the W chromosome, is required to determine femaleness. Based on a comparison of the normal W-chromosome and 7 translocation and W-deletion strains we present a map of Fem relative to the 12 W-specific RAPD markers.
|
| Volume |
133(3)
|
| Pages |
269-82
|
| Published |
2008-7-1
|
| DOI |
10.1007/s10709-007-9210-1
|
| PMID |
17901928
|
| MeSH |
Animals
Bombyx / genetics*
Chromosome Breakage / radiation effects
Chromosomes, Artificial, Bacterial / genetics
Female
Genetic Markers / genetics
Male
Meiosis / genetics
Polymerase Chain Reaction
Random Amplified Polymorphic DNA Technique
Sex Chromosomes / genetics*
Sex Determination Processes*
X-Rays
|
| IF |
1.186
|
| Times Cited |
30
|
|
WOS Category
|
GENETICS & HEREDITY
|
| Resource |
| Silkworms |
p50 |
