title: X chromosome-induced reversion of chromosome segregation in mouse/Chinese hamster somatic cell hybrids. Cellular recognition of native and foreign X chromosomes.
abstract: The direction of chromosome loss in two sets of mouse-Chinese hamster hybrids was compared with the direction of segregation of the same hybrids, to which an additional X chromosome derived from either of the mouse sarcoma lines MethAa, MethAs, or CMS4, was introduced at the time of the fusion. The addition of the X chromosome was carried out by substituting in place of the Chinese hamster parent a mouse X containing microcell hybrid of the latter. It was found that the addition of an X chromosome reverses the direction of chromosome segregation, but it can do so only if the mouse parent in the hybridization is different from the line from which the X originated. The possible reasons for recognition by the cells of a native and a foreign X are discussed. The existence of a multigene family on the X chromosome, involved in this recognition, is proposed.
mesh_terms: D000818:Animals; D002459:Cell Fusion; D002460:Cell Line; D002875:Chromosomes / Q000502:physiology*; D006224:Cricetinae; D005260:Female; D005796:Genes; D006822:Hybrid Cells / Q000648:ultrastructure*; D007621:Karyotyping; D008168:Lung; D051379:Mice; D012513:Sarcoma, Experimental; D012730:Sex Chromosomes / Q000502:physiology*; D014960:X Chromosome / Q000502:physiology*