Casein kinase II phosphorylates the fragile X mental retardation protein and modulates its biological properties

Mikiko C. Siomi, Kyoko Higashijima, Akira Ishizuka, Haruhiko Siomi

研究成果: Article査読

75 被引用数 (Scopus)

抄録

Fragile X syndrome is caused by loss of FMR1 protein expression. FMR1 binds RNA and associates with polysomes in the cytoplasm; thus, it has been proposed to function as a regulator of gene expression at the posttranscriptional level. Posttranslational modification of FMR1 had previously been suggested to regulate its activity, but no experimental support for this model has been reported to date. Here we report that FMR1 in Drosophila melanogaster (dFMR1) is phosphorylated in vivo and that the homomer formation and the RNA-binding activities of dFMR1 are modulated by phosphorylation in vitro. Identification of a protein phosphorylating dFMR1 showed it to be Drosophila casein kinase II (dCKII). dCKII directly interacts with and phosphorylates dFMR1 in vitro. The phosphorylation site in dFMR1 was identified as Ser406, which is highly conserved among FMR1 family members from several species. Using mass spectrometry, we established that Ser406 of dFMR1 is indeed phosphorylated in vivo. Furthermore, human FMR1 (hFMR1) is also phosphorylated in vivo, and alteration of the conserved Ser500 in hFMR1 abolishes phosphorylation by CKII in vitro. These studies support the model that the biological functions of FMR1, such as regulation of gene expression, are likely regulated by its phosphorylation.

本文言語English
ページ(範囲)8438-8447
ページ数10
ジャーナルMolecular and cellular biology
22
24
DOI
出版ステータスPublished - 2002 12
外部発表はい

ASJC Scopus subject areas

  • 分子生物学
  • 細胞生物学

フィンガープリント

「Casein kinase II phosphorylates the fragile X mental retardation protein and modulates its biological properties」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル