Igal Szleifer, Ph.D.

A single cell contains the genetic instructions for an entire organism. This genomic information is managed and processed by the complex machinery of chromatin — a mix of DNA and protein within chromosomes whose function and role in disease are of increasing interest to scientists.

A Northwestern University research team — using mathematical modeling and optical imaging they developed themselves — has discovered how chromatin folds at the single-cell level. The researchers found chromatin is folded into a variety of tree-like domains spaced along a chromatin backbone. These small and large areas are like a mixed forest of trees growing from the forest floor. The overall structure is a 3D forest at microscale… Continue reading.

Each cell in the human body holds a full two meters of DNA. In order for that DNA to fit into the cell nucleus — a cozy space just one hundredth of a millimeter of space — it needs to be packed extremely tight.

A new Northwestern University study has discovered that the packing of the three-dimensional genome structure, called chromatin, controls how cells respond to stress. When the chromatin packing is heterogenous and disordered, a cell demonstrates more plasticity. When the packing is neat and orderly, a cell cannot respond as easily to outside stressors.

This discovery comes with both good and bad news… Continue reading.

To advance the engineering of biology at the molecular and cellular levels, the National Science Foundation (NSF) has awarded $16 million for research to characterize the regulation of gene activity and expression, and to create strategies to modify those processes without altering the DNA sequence.

Chromatin — a combination of DNA, RNA and proteins within a cell’s nucleus — can be modified by attaching additional molecules. This can cause altered gene expression without actually changing the cell’s DNA. These so-called epigenetic changes can alter an organism’s traits, or phenotype, and may even be passed to offspring.

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The NSF EFRI Chromatin and Epigenetic Engineering (CEE) investment will support potentially transformative research by eight interdisciplinary teams:

• Ascribing function to chromatin with coordinated live-cell epigenomic sensors and scalpels, Albert Keung, North Carolina State University, with Caroline Laplante and Balaji Rao
• Engineering technologies to determine causal relationships between chromatin structure and gene regulation, Charles Gersbach, Duke University, with Brenton Hoffman, Michael Rubinstein and Xiling Shen
• Epigenetic cell reprogramming in situ: A novel tool for regenerative engineering, Guillermo Ameer, Northwestern University, with Panagiotis Ntziachristos and Hariharan Subramanian
• Epigenomic regulation over multiple length scales: Understanding chromatin modifications through label free imaging and multi-scale modeling, Juan De Pablo, University of Chicago, with Ali Shilatifard and Hao Zhang
• Human cardiac opto-epigenetics with HDAC inhibitors, Emilia Entcheva, George Washington University, with Shu Jia, Zhenyu Li, Ralph Mazitschek and Alejandro Villagra
• Macrogenomic engineering via modulation of chromatin nanoenvironment, Vadim Backman, Northwestern University, with Michael Kennedy, Hemant Roy and Igal Szleifer
• Optically controlled localized epigenetic chromatin remodeling with photoactivatable CRISPR-dCas9, Lev Perelman, Beth Israel Deaconess Medical Center, with Irving Itzkan, J. Thomas Lamont, Le Qiu and Darren Roblyer
• Sculpting the genome by design: Epigenetic and chromatin looping inputs to measure and manipulate chromatin organization and dynamics, Megan King, Yale University, with Simon G. Mochrie and Corey O’Hern

Continue reading…

Igal Szleifer, the Christina Enroth-Cugell Professor of Biomedical Engineering in McCormick. Szleifer was chosen for his distinguished contributions to the field of biomaterials and biointerfaces, particularly for theoretical modeling of molecular organization and biorelated function in polymer modified surfaces.