Developing de novo human artificial chromosomes in embryonic stem cells using HSV-1 amplicon technology

Area of Science:

• Cell Biology
• Genetics
• Molecular Biology

Background:

• Human artificial chromosomes (HACs) are functional, extrachromosomal elements that mimic endogenous chromosomes.
• De novo HACs are generated by delivering alpha satellite DNA into cells and are known for mitotic stability.
• HACs serve as valuable models for studying centromere formation and chromosome organization.

Purpose of the Study:

• To develop a method for generating de novo human artificial chromosomes (HACs) in human embryonic stem cells (hESc).
• To evaluate the efficacy of HSV-1 amplicons as a delivery system for HAC formation.
• To assess the stability and functionality of HACs during cell differentiation and in vivo studies.

Main Methods:

• Delivery of alpha satellite DNA into hESc using a highly efficient HSV-1 amplicon system.
• Development of an improved protocol for hESc chromosome harvesting to detect HACs.
• Analysis of HAC stability and maintenance through embryoid body formation, teratoma generation in mice, and neuronal differentiation.

Main Results:

• Stably generated de novo HACs in hESc at high frequency using HSV-1 amplicon delivery.
• HACs remained intact in the host ES genome, unlike integration observed in tumor cells.
• HACs were maintained through differentiation into embryoid bodies, teratomas, and neuronal cells, exhibiting similar structure and chromatin composition to endogenous chromosomes.

Conclusions:

• HSV-1 amplicon-based delivery is an effective method for generating de novo HACs in hESc.
• De novo HACs are mitotically stable and can be maintained through various differentiation pathways.
• HACs represent a promising tool for gene expression studies and gene therapy applications due to their stability and large capacity.