Dynamics of the transcriptome during chicken embryo development based on primordial germ cells

Abstract

Objective Regulation of gene expression during embryo development on the basis of migration of primordial germ cells (PGCs) in vivo has been rarely studied due to limited cell number and the necessity to isolate PGCs from a large number of embryos. Moreover, little is known about the comprehensive dynamics of the transcriptome in chicken PGCs during early developmental stages. The current study investigated transcriptome dynamics of chicken PGCs at key developmental stages: 4.5, 8 and 12 days of embryo incubation. PGCs were collected, and RNA was isolated using a commercial kit for single cells. The isolated RNA was subjected to microarray analysis (Agilent Technologies). Results Between 8 and 12 days of incubation, the highest number of genes was regulated. These data indicate that the most intense biological activity occurs between 8 and 12 days of embryo development. Heat map showed a significant decrease in gene expression on day 8, while it increased on day 12. The development of a precise method to isolate bird PGCs as well as the method to isolate RNA from single cells isolated from one embryo allows for early molecular analysis and detection of transcriptome changes during embryonic development.

Comparison of the Transcriptomic and Epigenetic Profiles of Gonadal Primordial Germ Cells of White Leghorn and Green-Legged Partridgelike Chicken Embryos

“…The gonads were cultured for up to 90 min at 37.8 °C in phosphate-buffered saline without Ca 2+ and Mg 2+ (PBS [–]) to obtain live gonadal germ cells. The discharged, viable PGCs were identified by the morphological criteria and qPCR identification [ 13 ]. The PGCs have a typically spherical shape with a nucleus as the pale rounded structure.…”

“…The DNA was assessed using a 2% agarose gel and a Nanodrop2000 spectrophotometer (Thermo-Fisher Scientific, Waltham, MA, USA). PGC-related markers were examined to show that the isolated nucleic acid was derived from PGCs, as described by Dunislawska et al [ 13 ].…”

“…In our previous study on gPGCs isolated from an intensively selected breed, White Leghorn (WL), we investigated the dynamics of the transcriptome during chicken embryo development [ 13 ]. We concluded that the changes in the gene expression depend on the time at which the PGCs were isolated during embryonic development and the highest number of genes was regulated between days 8 and 12 of an incubation.…”

Chicken embryo as a model in epigenetic research

“…Consequently, germline chimera can be produced by germ cell transfer into a blood vessel ( Han et al., 2002 ) and used as a model in the interaction studies of the donor–recipient cells. Moreover, the development of a precise method for bird PGC isolation ( Nakajima et al., 2011 ) and a method for RNA isolation from single cells obtained from an embryo can allow to perform early molecular analysis and detection of transcriptome changes during embryonic development ( Dunislawska et al., 2020b ).…”

“…The study of Dunislawska et al. (2020b) was the first step toward understanding the epigenetic regulation of gene expression in gonadal PGCs during embryonic development of White Leghorn.…”