RRC ID 3487
Author Fujii T, Yokoyama T, Ninagi O, Kakehashi K, Obara Y, Nenoi M, Ishikawa T, Mita K, Shimada T, Abe H.
Title Isolation and characterization of sex chromosome rearrangements generating male muscle dystrophy and female abnormal oogenesis in the silkworm, Bombyx mori.
Journal Genetica
Abstract In deletion-mapping of W-specific RAPD (W-RAPD) markers and putative female determinant gene (Fem), we used X-ray irradiation to break the translocation-carrying W chromosome (W( Ze )). We succeeded in obtaining a fragment of the W( Ze ) chromosome designated as Ze (W), having 3 of 12 W-RAPD markers (W-Bonsai, W-Yukemuri-S, W-Yukemuri-L). Inheritance of the Ze (W) fragment by males indicates that it does not include the Fem gene. On the basis of these results, we determined the relative positions of W-Yukemuri-S and W-Yukemuri-L, and we narrowed down the region where Fem gene is located. In addition to the Ze (W) fragment, the Z chromosome was also broken into a large fragment (Z(1)) having the +( sch ) (1-21.5) and a small fragment (Z(2)) having the +( od ) (1-49.6). Moreover, a new chromosomal fragment (Ze (W)Z(2)) was generated by a fusion event between the Ze (W) and the Z(2) fragments. We analyzed the genetic behavior of the Z(1) fragment and the Ze (W)Z(2) fragment during male (Z/Z(1) Ze (W)Z(2)) and female (Z(1) Ze (W)Z(2)/W) meiosis using phenotypic markers. It was observed that the Z(1) fragment and the Z or the W chromosomes separate without fail. On the other hand, non-disjunction between the Ze (W)Z(2) fragment and the Z chromosome and also between the Ze (W)Z(2) fragment and the W chromosome occurred. Furthermore, the females (2A: Z/Ze (W)Z(2)/W) and males (2A: Z/Z(1)) resulting from non-disjunction between the Ze (W)Z(2) fragment and the W chromosome had phenotypic defects: namely, females exhibited abnormal oogenesis and males were flapless due to abnormal indirect flight muscle structure. These results suggest that Z(2) region of the Z chromosome contains dose-sensitive gene(s), which are involved in oogenesis and indirect flight muscle development.
Volume 130(3)
Pages 267-80
Published 2007-7-1
DOI 10.1007/s10709-006-9104-7
PMID 17031495
MeSH Animals Bombyx / genetics* Chromosome Aberrations* Chromosome Mapping Female Gene Deletion Genetic Markers Male Models, Genetic Muscular Dystrophies / genetics Oogenesis Sex Chromosomes* Sex Factors Translocation, Genetic
IF 1.186
Times Cited 6
Silkworms p50