TY - JOUR
T1 - Regulated unmasking of in vivo synthesized maternal mRNA at oocyte maturation
T2 - A role for the chaperone nucleoplasmin
AU - Meric, Funda
AU - Matsumoto, Ken
AU - Wolffe, Alan P.
PY - 1997/5/9
Y1 - 1997/5/9
N2 - We examine the translational regulation of histone H4 mRNA when Xenopus laevis oocytes are induced to mature with progesterone. Histone H4 mRNA synthesized from plasmid templates microinjected into oocyte nuclei is translationally silenced (masked). This masked mRNA becomes translationally active only after oocyte maturation. In contrast, histone H4 mRNA injected into the oocyte cytoplasm is translationally active both before and after oocyte maturation. Thus, transcription in vivo is required to mask histone H4 mRNA and to allow subsequent translational regulation. Protein association with histone H4 mRNA synthesized in vivo was determined before and after oocyte maturation. UV crosslinking of radiolabeled RNA to protein and immunoprecipitation of crass-linked proteins reveals an increased association of the chaperone nucleoplasmin with ribonucleoprotein particles dependent on the oocyte maturation process. The Y-box protein FRGY2 inhibits translation of histone H4 mRNA in vitro. Nucleoplasmin is able to partially relieve this repression. We discuss the potential role of nucleoplasmin in the remodeling of repressive ribonucleoprotein particles containing maternal mRNA to facilitate translational activation.
AB - We examine the translational regulation of histone H4 mRNA when Xenopus laevis oocytes are induced to mature with progesterone. Histone H4 mRNA synthesized from plasmid templates microinjected into oocyte nuclei is translationally silenced (masked). This masked mRNA becomes translationally active only after oocyte maturation. In contrast, histone H4 mRNA injected into the oocyte cytoplasm is translationally active both before and after oocyte maturation. Thus, transcription in vivo is required to mask histone H4 mRNA and to allow subsequent translational regulation. Protein association with histone H4 mRNA synthesized in vivo was determined before and after oocyte maturation. UV crosslinking of radiolabeled RNA to protein and immunoprecipitation of crass-linked proteins reveals an increased association of the chaperone nucleoplasmin with ribonucleoprotein particles dependent on the oocyte maturation process. The Y-box protein FRGY2 inhibits translation of histone H4 mRNA in vitro. Nucleoplasmin is able to partially relieve this repression. We discuss the potential role of nucleoplasmin in the remodeling of repressive ribonucleoprotein particles containing maternal mRNA to facilitate translational activation.
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U2 - 10.1074/jbc.272.19.12840
DO - 10.1074/jbc.272.19.12840
M3 - Article
C2 - 9139745
AN - SCOPUS:0030924697
SN - 0021-9258
VL - 272
SP - 12840
EP - 12846
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 19
ER -