title: Matrix metalloproteinase-9 maps to the distal end of chromosome 2 in the mouse.
abstract: The activity and expression of matrix metalloproteinase-9/gelatinase B (MMP-9), an enzyme implicated in the implantation process in mice, was investigated in normal and parthenogenetic blastocyst outgrowths. Conditioned media from parthenogenetic blastocysts after 4 days of culture had reduced levels of MMP-9 activity compared to conditioned medium from normal outgrowths. Levels of MMP-9 mRNA assayed by reverse transcription-polymerase chain reaction methods were also reduced in parthenogenetic blastocysts compared to normal outgrowths. Genetic mapping studies showed that Mmp9 maps to the distal end of chromosome 2 near the proximal boundary of a region affected by genomic imprinting. Both parental alleles of Mmp9, however, are expressed in 11.5-day embryos derived from interspecific crosses of Mus musculus and Mus spretus. Thus, loss of MMP-9 activity in parthenogenetic blastocysts does not appear to be due to imprinting but, rather, due to a defect of trophoblast giant cell proliferation and differentiation.
authors.affiliation: Ontario Cancer Institute, Princess Margaret Hospital, Toronto, Canada.
authors.forename: K J
authors.initials: KJ
authors.lastname: Leco
authors.forename: M B
authors.initials: MB
authors.lastname: Harvey
authors.forename: A
authors.initials: A
authors.lastname: Hogan
authors.forename: N G
authors.initials: NG
authors.lastname: Copeland
authors.forename: D J
authors.initials: DJ
authors.lastname: Gilbert
authors.forename: N A
authors.initials: NA
authors.lastname: Jenkins
authors.forename: D R
authors.initials: DR
authors.lastname: Edwards
authors.forename: G A
authors.initials: GA
authors.lastname: Schultz
mesh_terms: D000818:Animals; D001755:Blastocyst / Q000378:metabolism*; D002874:Chromosome Mapping; D002875:Chromosomes; D017364:Collagenases / Q000235:genetics* / Q000378:metabolism; D020780:Matrix Metalloproteinase 9; D051379:Mice; D010312:Parthenogenesis
chemical_list: D017364:Collagenases; D020780:Matrix Metalloproteinase 9