Expression of paternal and maternal mitochondrial HSP70 family, hsc74, in preimplantation mouse embryos.
We have investigated the regulation of gene expression of a novel mitochondrial HSP70 family, hsc74 in preimplantation mouse embryos. We used a monoclonal antibody, anti-CSA, which reacts with only one of strain variants of the hsc74. By immunostaining with anti-CSA antibody, the hsc74 protein was constitutively detected in C3H embryos from 1-cell to blastocyst stage, but no signals were detectable in C57BL/6 embryos. To know the timing of paternal genome expression, we examined the expression of hsc74 in (C57BL/6 x C3H)F1 embryos. No positive signals were detectable in embryos before 8-cell stage. In early 8-cell stage weakly positive signals appeared in the peripheral region of the blastomeres. From late 8-cell stage, the protein was intensively detectable and was persistently expressed in all types of cells. We have also applied a sensitive methodology to distinguish genetic variants of hsc74 from C3H and C57BL/6 by reverse transcription polymerase chain reaction followed by single strand conformation polymorphism analysis. In (C57BL/6 x C3H)F1 embryos, the paternal transcripts were first detected in 4-cell embryos, while the maternal transcripts were constantly detectable. These results indicate that the transcripts and proteins of hsc74 were derived only from the maternal gene from 1-cell to 4-cell stages, and that from 4-cell stage the paternal gene is also transcribed, and the significant increase of the paternally derived protein occurred around late 8-cell stage.
Dvorak
P
P
Laboratory of Cell Biology, Tsukuba Life Science Center, Institute of Physical and Chemical Research (RIKEN), Ibaraki, Japan.
Dvorakova
D
D
Yoshiki
A
A
Ohashi
T
T
Kitamura
K
K
Kusakabe
M
M
D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D001483:Base Sequence; D001755:Blastocyst / Q000378:metabolism*; D015153:Blotting, Western; D017931:DNA Primers; D004622:Embryo, Mammalian / Q000378:metabolism / Q000502:physiology; D005314:Embryonic and Fetal Development; D005260:Female; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D008214:Lymphocytes / Q000276:immunology; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000378:metabolism*; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D012680:Sensitivity and Specificity; D013045:Species Specificity
D000911:Antibodies, Monoclonal; D017931:DNA Primers; D018840:HSP70 Heat-Shock Proteins