Nuclear Transfer Arrest Embryos Show Massive Dysregulation of Genes Involved in Transcription Pathways

Area of Science:

• Developmental Biology
• Reproductive Biology
• Molecular Biology

Background:

• Somatic cell nuclear transfer (SCNT) aims to reprogram differentiated cells into a totipotent state.
• Understanding molecular barriers in SCNT embryo development is crucial for improving efficiency.
• Incomplete epigenetic reprogramming is a known challenge in SCNT.

Purpose of the Study:

• To investigate the role of transcription-related pathways in SCNT embryo development.
• To identify molecular barriers hindering the development of SCNT embryos.
• To elucidate the gene regulatory networks (GRNs) associated with aberrant transcription in SCNT.

Main Methods:

• Comparative analysis of gene expression in nuclear transfer arrest (NTA) embryos, normal SCNT embryos, and in vivo fertilized (WT) embryos.
• Identification and analysis of transcription pathway-associated gene regulatory networks (GRNs).
• Assessment of gene dysregulation and functional synergy in NTA embryos.

Main Results:

• Transcription-related pathways were incompletely activated in NTA embryos compared to normal SCNT and WT embryos.
• Aberrant transcription pathways led to massive gene dysregulation in NTA embryos.
• Crucial genes for catabolism, pluripotency, epigenetics, and signaling showed inhibited and defective synergy in NTA embryos.

Conclusions:

• Incomplete activation of transcription pathways is a significant molecular barrier in SCNT embryo development.
• This barrier acts in concert with incomplete epigenetic reprogramming.
• Findings broaden the understanding of the molecular mechanisms underlying SCNT embryonic development.