Eszter Posfai

Eszter Posfai is an Assistant Professor in the Department of Molecular Biology at Princeton University, where she leads the Posfai Lab focused on quantitative approaches to understanding mammalian preimplantation embryo formation. Her research integrates developmental biology, stem cell biology, biophysics, and imaging technologies to dissect the mechanisms of cell fate decisions, embryonic patterning, and totipotency.

Research Interests:

• Quantitative analysis of mammalian embryo development
• Mechanisms of cell fate specification and symmetry breaking
• Role of mechanical forces in embryogenesis
• Molecular basis of totipotency in vivo and in vitro
• Development of synthetic embryo models from stem cells
• Live imaging and genome engineering (CRISPR-based tools)

The lab employs advanced imaging techniques, including light sheet microscopy, and develops computational tools for image analysis. They have pioneered CRISPR/Cas9-based methods for large DNA fragment insertions in mouse embryos, enabling precise interrogation of gene function.

The recent publications reflect a strong focus on developmental dynamics, totipotency evaluation, and innovative genetic tool development. These works span disciplines such as developmental biology, biophysics, and genome engineering, with applications in stem cell modeling and synthetic embryology.

Scientific Contributions:

• Co-development of 2-cell HR-CRISPR for efficient knock-in mouse models
• Establishment of criteria for evaluating totipotency
• Live imaging approaches for developmental cell cycles
• Novel mouse models for planar cell polarity studies

Advising & Collaborations: The lab welcomes prospective graduate students and postdoctoral researchers, particularly those with expertise in imaging and data analysis. While no current students are listed, the lab fosters interdisciplinary collaborations involving computational modeling and image analysis. Although specific grants are not mentioned, her technical innovations suggest significant funding support for method development and embryogenesis research.

Laboratory: The Posfai Lab at Princeton's Thomas Laboratory emphasizes 'seeing is believing'—prioritizing direct visualization of developmental processes. The lab actively develops live imaging and genome editing tools to probe molecular events in real time and build quantitative models of embryonic development.