Matrix metalloproteinase-9 maps to the distal end of chromosome 2 in the mouse.
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.
Leco
K J
KJ
Ontario Cancer Institute, Princess Margaret Hospital, Toronto, Canada.
Harvey
M B
MB
Hogan
A
A
Copeland
N G
NG
Gilbert
D J
DJ
Jenkins
N A
NA
Edwards
D R
DR
Schultz
G A
GA
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
D017364:Collagenases; D020780:Matrix Metalloproteinase 9