Inhibiting repressive epigenetic modification promotes telomere rejuvenation in somatic cell reprogramming

Area of Science:

• Reproductive biology
• Epigenetics
• Developmental biology

Background:

• Somatic cell nuclear transfer (SCNT) has low efficiency in producing cloned animals.
• Telomere length and epigenetic modifications are crucial for successful reprogramming.

Purpose of the Study:

• To investigate the role of telomere rejuvenation in SCNT reprogramming.
• To identify small molecules that can improve SCNT efficiency.
• To elucidate the mechanisms by which melatonin affects SCNT embryos.

Main Methods:

• Small-molecule screening for improved SCNT efficiency.
• Embryonic biopsy and single-cell RNA sequencing.
• Quantitative FISH for telomere length analysis.
• Analysis of epigenetic modifications (DNA methylation, histone modifications).

Main Results:

• Melatonin significantly improved in vitro and in vivo developmental competence of SCNT embryos.
• Melatonin attenuated zygotic genome activation defects and facilitated telomere elongation.
• Melatonin inhibited heterochromatic epigenetic modifications and increased activation markers.
• Combined use of melatonin-treated embryos and recipients synergistically enhanced cloned animal production.

Conclusions:

• Telomere rejuvenation is critical for SCNT reprogramming efficiency.
• Melatonin is a promising small molecule for improving SCNT outcomes.
• Melatonin acts by inhibiting repressive epigenetic modifications and promoting telomere elongation.
• This study provides novel insights into melatonin's role in SCNT and telomere biology.