Nepro is localized in the nucleolus and essential for preimplantation development in mice. (14th July 2015)

• Record Type: Journal Article
• Authors: Hashimoto, Masakazu; Sato, Tatsuya; Muroyama, Yuko; Fujimura, Lisa; Hatano, Masahiko; Saito, Tetsuichiro
• Is Part Of: Development growth and differentiation. Volume 57:Number 7(2015)
• Page Start: 529
• Page End: 538
• Publication Date: 2015-07-14
• Subjects: Embryology -- Periodicals; Developmental biology -- Periodicals; Growth -- Periodicals; 574.3
• DOI: 10.1111/dgd.12232
• Languages: English
• ISSNs: 0012-1592

Abstract

<abstract abstract-type="main" id="dgd12232-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>We generated knockout (KO) mice of <italic>Nepro</italic>, which has been shown to be necessary to maintain neural progenitor cells downstream of Notch in the mouse developing neocortex by using knockdown experiments, to explore its function in embryogenesis. <italic>Nepro </italic>KO embryos were morphologically indistinguishable from wild type (WT) embryos until the morula stage but failed in blastocyst formation, and many cells of the KO embryos resulted in apoptosis. We found that Nepro was localized in the nucleolus at the blastocyst stage. The number of nucleolus precursor bodies (NPBs) and nucleoli per nucleus was significantly higher in <italic>Nepro </italic>KO embryos compared with WT embryos later than the 2‐cell stage. Furthermore, at the morula stage, whereas 18S rRNA and ribosomal protein S6 (rpS6), which are components of the ribosome, were distributed to the cytoplasm in WT embryos, they were mainly localized in the nucleoli in <italic>Nepro </italic>KO embryos. In addition, in <italic>Nepro </italic>KO embryos, the amount of the mitochondria‐associated p53 protein increased, and Cytochrome <italic>c</italic> was distributed in the cytoplasm. These findings indicate that Nepro is a nucleolus‐associated protein, and its loss leads to the apoptosis before blastocyst formation in mice.</p> </abstract>