title: Nuclear translocation of phospholipase C-zeta, an egg-activating factor, during early embryonic development.
abstract: Phospholipase C-zeta (PLCzeta), a strong candidate of the egg-activating sperm factor, causes intracellular Ca2+ oscillations and egg activation, and is subsequently accumulated into the pronucleus (PN), when expressed in mouse eggs by injection of RNA encoding PLCzeta. Changes in the localization of expressed PLCzeta were investigated by tagging with a fluorescent protein. PLCzeta began to translocate into the PN formed at 5-6 h after RNA injection and increased there. Observation in the same embryo revealed that PLCzeta in the PN dispersed to the cytoplasm upon nuclear envelope breakdown and translocated again into the nucleus after cleavage. The dynamics was found in the second mitosis as well. When RNA was injected into fertilization-originated 1-cell embryos or blastomere(s) of 2-8-cell embryos, the nuclear localization of expressed PLCzeta was recognized in every embryo up to blastocyst. Thus, PLCzeta exhibited alternative cytoplasm/nucleus localization during development. This supports the view that the sperm factor could control cell cycle-dependent generation of Ca2+ oscillations in early embryogenesis.
authors.affiliation: Department of Physiology, Tokyo Women's Medical University School of Medicine, Tokyo 162-8666, Japan.
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Sone
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ito
authors.forename: Hideki
authors.initials: H
authors.lastname: Shirakawa
authors.forename: Tomohide
authors.initials: T
authors.lastname: Shikano
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Kinoshita
authors.forename: Shunichi
authors.initials: S
authors.lastname: Miyazaki
mesh_terms: D021581:Active Transport, Cell Nucleus; D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000201:enzymology; D002467:Cell Nucleus / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000196:embryology* / Q000201:enzymology*; D047108:Embryonic Development; D005260:Female; D051379:Mice; D010063:Ovum / Q000378:metabolism*; D054801:Phosphoinositide Phospholipase C; D013997:Time Factors; D010738:Type C Phospholipases / Q000378:metabolism*
chemical_list: D010738:Type C Phospholipases; D054801:Phosphoinositide Phospholipase C; C499234:Plcz1 protein, mouse