Molecular Biology Program

The John Maciejowski Lab

John Maciejowski, PhD

Associate Professor

The nuclear envelope is a regulated membrane barrier that separates the nucleus from the cytosol in eukaryotes. Although the NE is often depicted as a static barrier, new research has identified conditions where nuclear envelope rupturing causes a loss of compartmentalization. Nuclear envelope ruptures are rapidly repaired in the nucleus, but persist at aberrant, nuclear compartments, such as micronuclei and DNA bridges, that form around mis-segregated chromosomes. Compromised nuclear compartmentalization can result in DNA damage, inflammation, and clustered mutagenesis. The Maciejowski lab seeks to understand how the nuclear envelope safeguards the genome and prevents immune recognition of chromosomal DNA. We approach these problems using a combination of cell biology, biochemistry, and genomics. More information about our research can be found at https://sites.google.com/view/maciejowskilab/home.

Research Projects

Telomere dysfunction threatens the integrity of the genome

Featured News

SKI molecular biologist John Maciejowski

SKI Study Sheds Light on How a Natural Defense Against Viruses Can Lead to Mutations in Cancer Cells

A protein in the body that protects against viruses can also cause cancer-related mutations.

In the Lab

Separation Anxiety: Cell Division Gone Awry Leads to Genetic Chaos

Researchers shed light on how aberrant cell division can cause the kind of mutations often found in cancer cells.

Publications Highlights

Mohr L, Toufektchan E, von Morgen P, Chu K, Kapoor A, Maciejowski J. ER-directed TREX1 limits cGAS activation at micronuclei. Mol Cell. 2021 Jan 12:S1097-2765(20)30958-8. doi: 10.1016/j.molcel.2020.12.037. Epub ahead of print.

Maciejowski J, Chatzipli A, Dananberg A, Chu K, Toufektchan E, Klimczak LJ, Gordenin DA, Campbell PJ, de Lange T. APOBEC3-dependent kataegis and TREX1-driven chromothripsis during telomere crisis. Nat Genet. 2020 Sep;52(9):884-890. doi: 10.1038/s41588-020-0667-5. Epub 2020 Jul 27. PMCID: PMC7484228.

Maciejowski J, Hatch EM. Nuclear Membrane Rupture and Its Consequences. Annu Rev Cell Dev Biol. 2020 Oct 6;36:85-114. doi: 10.1146/annurev-cellbio-020520-120627. Epub 2020 Jul 21.

Petljak M, Maciejowski J. Molecular origins of APOBEC-associated mutations in cancer. DNA Repair (Amst). 2020 Oct;94:102905. doi: 10.1016/j.dnarep.2020.102905. Epub 2020 Jul 6. PMCID: PMC7494591

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People

John Maciejowski, PhD

Associate Professor

Molecular biologist John Maciejowski studies the causes of complex chromosome rearrangements and the patterns of hypermutation that shape cancer genomes.
PhD, Louis V. Gerstner, Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center

[email protected]: Email Address

Members

Chen Yanyang — Yanyang Chen
Graduate Research Assistant

Alexandra Dananberg
Graduate Research Assistant

Marton Kovacs — Marton T. Kovacs
Research Fellow

John Maciejowski
Assistant Professor, Memorial Sloan Kettering Cancer Center, New York, NY

Ashley Nichols
Graduate Research Assistant

Hannah Rosenberg
Graduate Research Assistant

Abraham Shim
Graduate Research Assistant

Josefine U. Striepen
Graduate Research Assistant

Lab Alumni

James Hickling
Senior Research Technician

Lisa Mohr, PhD — Lisa Mohr
Research Fellow

Lab Affiliations

Achievements

NIH Pathway to Independence Award (2016)
Tri-Institutional Breakout Prize for Junior Investigators (2016)
Regeneron Prize for Creative Innovation (2016)
Pew Biomedical Scholar

Lab News & Events

Upcoming event

Mechanisms Driving Evolution of Drug Resistance in Lung Cancer

Wednesday, February 26, 2025 - 1:00 PM to 2:00 PM

Memorial Sloan Kettering Cancer Center
Rockefeller Research Laboratories
430 East 67th Street
RRL-120 (Auditorium)
New York, NY 10065

Open Positions

To learn more about available postdoctoral opportunities, please visit our Career Center

To learn more about compensation and benefits for postdoctoral researchers at MSK, please visit Resources for Postdocs

Open Positions

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Get in Touch

[email protected]

Lab Head Email

Disclosures

Doctors and faculty members often work with pharmaceutical, device, biotechnology, and life sciences companies, and other organizations outside of MSK, to find safe and effective cancer treatments, to improve patient care, and to educate the health care community.

MSK requires doctors and faculty members to report (“disclose”) the relationships and financial interests they have with external entities. As a commitment to transparency with our community, we make that information available to the public.

John Maciejowski discloses the following relationships and financial interests:

Merck & Co Inc.
Intellectual Property Rights

The information published here is a complement to other publicly reported data and is for a specific annual disclosure period. There may be differences between information on this and other public sites as a result of different reporting periods and/or the various ways relationships and financial interests are categorized by organizations that publish such data.

This page and data include information for a specific MSK annual disclosure period (January 1, 2023 through disclosure submission in spring 2024). This data reflects interests that may or may not still exist. This data is updated annually.

Learn more about MSK’s COI policies here. For questions regarding MSK’s COI-related policies and procedures, email MSK’s Compliance Office at [email protected].

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