foxm1 Modulates Cell Non-Autonomous Response in Zebrafish Skeletal Muscle Homeostasis.

Area of Science:

• Molecular Biology
• Developmental Biology
• Muscle Biology

Background:

• FOXM1 is a key regulator of the cell cycle and proliferation.
• Emerging evidence suggests FOXM1 has non-proliferative roles.
• These non-proliferative functions are not well understood.

Purpose of the Study:

• To investigate the role of FOXM1 in terminally differentiated muscle cells.
• To explore the non-proliferative functions of FOXM1.
• To assess the impact of CRISPR/Cas9 mediated FOXM1 disruption in vivo.

Main Methods:

• CRISPR/Cas9 gene editing was used to disrupt the FOXM1 gene.
• Experiments were conducted in zebrafish fast-twitching muscle cells.
• Myofiber death, clearance, and satellite cell activation were analyzed.

Main Results:

• FOXM1 disruption led to increased myofiber death and clearance.
• This disruption triggered non-autonomous satellite cell activation and proliferation.
• High Cas9 expression alone exhibited significant toxicity to muscle cells.

Conclusions:

• FOXM1 plays a role in modulating muscle's non-autonomous response to myofiber death.
• The study highlights potential toxicity associated with high Cas9 expression in vivo.
• FOXM1's involvement in muscle homeostasis extends beyond cell proliferation.