Rapid replacement of somatic linker histones with the oocyte-specific linker histone H1foo in nuclear transfer.
The most distinctive feature of oocyte-specific linker histones is the specific timing of their expression during embryonic development. In Xenopus nuclear transfer, somatic linker histones in the donor nucleus are replaced with oocyte-specific linker histone B4, leading to the involvement of oocyte-specific linker histones in nuclear reprogramming. We recently have discovered a mouse oocyte-specific linker histone, named H1foo, and demonstrated its expression pattern in normal preimplantation embryos. The present study was undertaken to determine whether the replacement of somatic linker histones with H1foo occurs during the process of mouse nuclear transfer. H1foo was detected in the donor nucleus soon after transplantation. Thereafter, H1foo was restricted to the chromatin in up to two-cell stage embryos. After fusion of an oocyte with a cell expressing GFP (green fluorescent protein)-tagged somatic linker histone H1c, immediate release of H1c in the donor nucleus was observed. In addition, we used fluorescence recovery after photobleaching (FRAP), and found that H1foo is more mobile than H1c in living cells. The greater mobility of H1foo may contribute to its rapid replacement and decreased stability of the embryonic chromatin structure. These results suggest that rapid replacement of H1c with H1foo may play an important role in nuclear remodeling.
Teranishi
Takahide
T
Department of Obstetrics and Gynecology, Keio University School of Medicine, Shinjuku, Tokyo 160-8582, Japan. gi006022@sc.itc.keio.ac.jp
Tanaka
Mamoru
M
Kimoto
Shingo
S
Ono
Yukiko
Y
Miyakoshi
Kei
K
Kono
Tomohiro
T
Yoshimura
Yasunori
Y
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002467:Cell Nucleus; D005455:Fluorescent Antibody Technique; D006657:Histones / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D009865:Oocytes / Q000502:physiology*; D010957:Plasmids; D014162:Transfection
D006657:Histones