Regulation of histone acetylation during meiotic maturation in mouse oocytes.
Histone acetylation is an important epigenetic modification implicated in the regulation of chromatin structure and, subsequently, gene expression. Global histone deacetylation was reported in mouse oocytes during meiosis but not mitosis. The regulation of this meiosis-specific deacetylation has not been elucidated. Here, we demonstrate that p34(cdc2) kinase activity and protein synthesis are responsible for the activation of histone deacetylases and the inhibition of histone acetyltransferases (HATs), respectively, resulting in deacetylation of histone H4 at lysine-12 (H4K12) during mouse oocyte meiosis. Temporal changes in the acetylation state of H4K12 were examined immunocytochemically during meiotic maturation using an antibody specific for acetylated H4K12. H4K12 was deacetylated during the first meiosis, temporarily acetylated around the time of the first polar body (PB1) extrusion, and then deacetylated again during the second meiosis. Because these changes coincided with the known oscillation pattern of p34(cdc2) kinase activity, we investigated the involvement of the kinase in H4K12 deacetylation. Roscovitine, an inhibitor of cyclin-dependent kinase activity, prevented H4K12 deacetylation during both the first and second meiosis, suggesting that p34(cdc2) kinase activity is required for deacetylation during meiosis. In addition, cycloheximide, a protein synthesis inhibitor, also prevented deacetylation. After PB1 extrusion, at which time H4K12 had been deacetylated, H4K12 was re-acetylated in the condensed chromosomes by treatment with cycloheximide but not with roscovitine. These results demonstrate that HATs are present but inactivated by newly synthesized protein(s) that is (are) not involved in p34(cdc2) kinase activity. Our results suggest that p34(cdc2) kinase activity induces the deacetylation of H4K12 and that the deacetylated state is maintained by newly synthesized protein(s) that inhibits HAT activity during meiosis.
Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Chiba, Japan.
Tomohiko
T
Akiyama
Jin-Moon
JM
Kim
Masao
M
Nagata
Fugaku
F
Aoki
D000107:Acetylation; D000123:Acetyltransferases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000818:Animals; D016203:CDC2 Protein Kinase / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D003513:Cycloheximide / Q000494:pharmacology; D005260:Female; D051548:Histone Acetyltransferases; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000378:metabolism*; D006657:Histones / Q000378:metabolism*; D066298:In Vitro Techniques; D008540:Meiosis; D051379:Mice; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011687:Purines / Q000494:pharmacology; D000077546:Roscovitine; D015398:Signal Transduction; D000095043:Cyclin-Dependent Kinase-Activating Kinase
D056572:Histone Deacetylase Inhibitors; D006657:Histones; D047428:Protein Kinase Inhibitors; D011687:Purines; D000077546:Roscovitine; D003513:Cycloheximide; D000123:Acetyltransferases; D051548:Histone Acetyltransferases; D016203:CDC2 Protein Kinase; D018844:Cyclin-Dependent Kinases; D006655:Histone Deacetylases; D000095043:Cyclin-Dependent Kinase-Activating Kinase