Centrosome Formation in the Bovine Early Embryo

Cells. 2023 May 7;12(9):1335. doi: 10.3390/cells12091335.

Abstract

Centrosome formation during early development in mice and rats occurs due to the appearance of centrioles de novo. In contrast, in humans and other non-rodent mammals, centrioles are thought to be derived from spermatozoa. Ultrastructural study of zygotes and early embryos of cattle at full series of ultrathin sections show that the proximal centriole of the spermatozoon disappears by the end of the first cleavage division. Centrioles appear in two to four cell embryos in fertilized oocytes and in parthenogenetic embryos. Centriole formation includes the appearance of atypical centrioles with randomly arranged triplets and centrioles with microtubule triplets of various lengths. After the third cleavage, four centriolar cylinders appear for the first time in the blastomeres while each embryo still has two atypical centrioles. Our results showed that the mechanisms of centriole formation in different groups of mammals are universal, differing only in the stage of development in which they occur.

Keywords: centriole; centrosome; cleavage divisions; early development; polar corpuscles; zygote.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Centrioles / ultrastructure
  • Centrosome* / ultrastructure
  • Humans
  • Male
  • Mammals
  • Mice
  • Oocytes* / ultrastructure
  • Rats
  • Spermatozoa / ultrastructure

Grants and funding

This project was supported by the Agriculture and Food Research Initiative Competitive Grant number OHOW-2020-02790 from the USDA National Institute of Food. Work on production of IVM/IVF/IVC embryos was funded by the Russian Science Foundation (project 19-16-00115-Π), and work on production parthenogenetic embryos was funded by the Ministry of Science and Higher Education of Russia (theme number 0445-2021-0004). The electron microscope data were obtained with the aid of the IBiSA Electron Microscopy Facility of the University of Tours and the University Hospital of Tours.