title: X-linked and autosomal inheritance patterns of homologous genes in two species of Tribolium.
abstract: The tenebrionid beetles Tribolium castaneum and T. confusum are representative of two distinct species groups within their genus. It has been suggested [Smith, S.G. (1952). J. Morphol. 91:325] that the 8AA + neo-XY karyotype of T. confusum was derived from the ancestral 9AA + XY formula, still present in T. castaneum, via the fusion of one pair of autosomes with the X and Y chromosomes during the early divergence of the confusum and castaneum species groups. In the present paper, electrophoretic variation in malic enzyme and hexokinase-1, detected in laboratory strains in Tribolium, is described. Evidence is presented that the genes encoding variation in both enzymes are autosomal in T. castaneum but are X linked in T. confusum. These species-specific patterns of inheritance of homologous gene loci are consistent with the hypothesized karyotypic history of the genus.
mesh_terms: D000818:Animals; D002875:Chromosomes / Q000502:physiology*; D001517:Coleoptera / Q000235:genetics*; D003433:Crosses, Genetic; D005260:Female; D005796:Genes; D014644:Genetic Variation; D006579:Heterozygote; D006593:Hexokinase / Q000235:genetics; D007621:Karyotyping; D046911:Macromolecular Substances; D008297:Male; D010641:Phenotype; D012730:Sex Chromosomes / Q000502:physiology*; D013045:Species Specificity; D014960:X Chromosome / Q000502:physiology*; D014998:Y Chromosome / Q000502:physiology
chemical_list: D046911:Macromolecular Substances; D006593:Hexokinase