Chromosome Research fulltext (original) (raw)

Abstract The small bristles (sbr) gene of Drosophila melanogaster belongs to the family of nuclear export factor (NXF) genes that participate in mRNA nuclear export. During meiosis, females of Drosophila melanogaster that carry various combinations of mutant alleles of the Dm nxf1/sbr gene exhibit disruption of the division spindle and misalignment of chromosomes at the metaphase plate. Meiosis of sbr5/+ females is characterized by the formation of tripolar spindles during the first cell division. According to the sequencing results, the sbr5 (l(1)K4) lethal allele is a deletion of 492 nucleotides. In SBR5 protein, 57 of the 146 amino acids that have been lost by deletion belong to the NTF2-like domain.