Open Close
Torres, M., Sanchez, L. (1992). The segmentation gene runt is needed to activate Sex-lethal, a gene that controls sex determination and dosage compensation in Drosophila.  Genet. Res. (Camb.) 59(3): 189--198.
FlyBase ID
Publication Type
Research paper

In Drosophila, sex is determined by the relative number of X chromosomes to autosomal sets ( X:A ratio). The amount of products from several X-linked genes, called sisterless elements, is used to indicate to Sex-lethal the relative number of X chromosomes present in the cell. In response to the X:A signal, Sex-lethal is activated in females but remains inactive in males, being responsible for the control of both sex determination and dosage compensation. Here we find that the X-linked segmentation gene runt plays a role in this process. Reduced function of runt results in female-specific lethality and sexual transformation of XX animals that are heterozygous for Sxl or sis loss-of-function mutations. These interactions are suppressed by SxlM1, a mutation that constitutively expresses female Sex-lethal functions, and occur at the time when the X:A signal determines Sex-lethal activity. Moreover, the presence of a loss-of-function runt mutation masculinizes triploid intersexes. On the other hand, runt duplications cause a reduction in male viability by ectopic activation of Sex-lethal. We conclude that runt is needed for the initial step of Sex-lethal activation, but does not have a major role as an X-counting element.

PubMed ID
PubMed Central ID
Associated Information
Associated Files
Other Information
Secondary IDs
    Language of Publication
    Additional Languages of Abstract
    Parent Publication
    Publication Type
    Genet. Res. (Camb.)
    Genetics research
    Publication Year
    0016-6723 1469-5073
    Data From Reference
    Aberrations (10)
    Alleles (11)
    Genes (10)