title: Hox11 controls the genesis of the spleen.
abstract: Many homeobox genes are clustered in a linear array along a chromosome, reflecting their ordered expression along the anterior-posterior axis of the embryo. Expression patterns as well as grafting, ectopic expression and loss-of-function experiments suggest that the Hox genes encode a combinatorial system of positional specification along that axis. In contrast, the function of orphan homeobox genes located at sites outside the four mammalian Hox clusters is less well understood. To assess the functional role of the orphan homeobox gene Hox11, we have generated Hox11-deficient mice through gene targeting. Hox11-/- mice have no spleen, but otherwise appear normal. Hox11 is normally expressed in the splenic anlage arising from the splanchnic mesoderm. Hox11-/- embryos have no cellular organization at the site of splenic development but all other splanchnic derivatives develop normally. Hox11 controls the genesis of a single organ, providing new insight into the genetic regulation of morphogenesis.
authors.affiliation: Howard Hughes Medical Institute, St Louis, Missouri 63110.
authors.forename: C W
authors.initials: CW
authors.lastname: Roberts
authors.forename: J R
authors.initials: JR
authors.lastname: Shutter
authors.forename: S J
authors.initials: SJ
authors.lastname: Korsmeyer
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D004247:DNA; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005260:Female; D005801:Genes, Homeobox / Q000502:physiology*; D018398:Homeodomain Proteins; D008297:Male; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D015513:Oncogene Proteins / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D009928:Organ Specificity; D011995:Recombination, Genetic; D013154:Spleen / Q000002:abnormalities / Q000196:embryology* / Q000378:metabolism; D013234:Stem Cells
chemical_list: D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D015513:Oncogene Proteins; C487378:Tlx1 protein, mouse; D004247:DNA