title: Targeted disruption of p107: functional overlap between p107 and Rb.
abstract: To explore the physiological role of p107, a member of retinoblastoma gene (Rb) family, we disrupted the mouse gene by homologous recombination in embryonic stem cells. p107 homozygous mutant mice were viable, fertile, and displayed no obvious abnormalities. To investigate possible functional overlap between p107 and Rb, mice with mutations at both loci were generated. Rb+/-;p107-/- mice have a pronounced growth retardation and increased mortality rate during the first 3 weeks after birth. The Rb+/-;p107-/- pups that survive to adulthood did not show any altered tumor predisposition when compared with Rb+/- mice but developed multiple dysplastic lesions of the retina. Embryos homozygous for both Rb and p107 died at approximately 11.5 days of gestation, 2 days earlier than embryos homozygous for Rb alone. Histological examination revealed accelerated apoptosis in the liver and the central nervous system of Rb-/-;p107-/- embryos relative to Rb-/- embryos. These results provide the first in vivo evidence that p107 and Rb have overlapping functions in some tissues of the developing and adult mouse.
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts 02129, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Lee
authors.forename: B O
authors.initials: BO
authors.lastname: Williams
authors.forename: G
authors.initials: G
authors.lastname: Mulligan
authors.forename: S
authors.initials: S
authors.lastname: Mukai
authors.forename: R T
authors.initials: RT
authors.lastname: Bronson
authors.forename: N
authors.initials: N
authors.lastname: Dyson
authors.forename: E
authors.initials: E
authors.lastname: Harlow
authors.forename: T
authors.initials: T
authors.lastname: Jacks
mesh_terms: D000199:Actins / Q000032:analysis; D000818:Animals; D017209:Apoptosis; D001483:Base Sequence; D001835:Body Weight; D002490:Central Nervous System / Q000473:pathology; D005260:Female; D018390:Gene Targeting; D016161:Genes, Retinoblastoma / Q000502:physiology*; D008099:Liver / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000737:chemistry; D009687:Nuclear Proteins / Q000235:genetics* / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D012160:Retina / Q000473:pathology; D015792:Retinal Dysplasia / Q000235:genetics*; D016160:Retinoblastoma Protein / Q000235:genetics* / Q000502:physiology; D050720:Retinoblastoma-Like Protein p107; D013234:Stem Cells
chemical_list: D000199:Actins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C489485:Rbl1 protein, mouse; D016160:Retinoblastoma Protein; D050720:Retinoblastoma-Like Protein p107