黑料吃瓜资源

The DNA packed inside every human cell contains instructions for life, written in billions of letters of genetic code. Every time a cell divides, the complete code, divided among 46 chromosomes, must be faithfully copied. This staggering task happens over and over with extraordinary precision.

Decades of research have revealed how dozens of proteins work together to copy chromosomes reliably. Now, 黑料吃瓜资源 (CSHL) President Bruce Stillman and colleagues have compiled these findings into a comprehensive view of the very first step: a 鈥渓icensing鈥� stage wherein many starting points for DNA replication on all chromosomes are assembled into an essential mechanism called the pre-replicative complex (pre-RC). It鈥檚 like a license for life itself.

Stillman has studied DNA replication for more than 40 years. 鈥淚鈥檝e focused on understanding one of the most fundamental processes in life,鈥� he says. In humans, the process unfolds billions of times a day. Missteps can increase one鈥檚 risk for cancer, autism, and congenital heart disease.

Throughout the 1980s and 鈥�90s, Stillman鈥檚 lab at CSHL uncovered crucial proteins that ensure DNA replication begins when and where it should. One of his earliest collaborators was a postdoc named John Diffley. For many years, Diffley has run his own lab at . Thanks in part to the two, scientists now know the identities of more than 100 proteins that need to replicate their genomes. Stillman recently reunited with Diffley to bundle all this knowledge into a neat package. They then brought in University of Utah cell biologist and animator Assistant Professor to bring that knowledge to life.

Stillman discovered another crucial component of DNA replication, the origin recognition complex (ORC), in 1991. Here, we see how ORC helps to establish the pre-RC in yeast. Video: Janet Iwasa/University of Utah

Looks detailed, right? Why would life require an intricate mechanism like the pre-RC? It鈥檚 all about efficiency. 鈥淚n bone marrow alone, about 500 million cells are born every minute, each requiring duplication of over 2 meters of DNA,鈥� Stillman explains. If chromosomes were copied from end to end, this would take months. Instead, cells copy many DNA segments at once. To coordinate, various starting points are marked along each chromosome. Markers are removed as sites are used. New marks cannot be placed until after the cell divides, so each segment only duplicates once per cycle.

Reading this is one thing, seeing it another. Stillman says provide invaluable education tools for biochemistry graduates at any career stage. They鈥檝e already inspired new experiments in his lab, testing how pre-RCs are established in different species. Throughout his long career, Stillman has encouraged colleagues investigating such fundamental processes to 鈥渢hink like a molecule.鈥� His latest publication offers new ways to do just that.

Written by: Jennifer Michalowski, Science Writer | [email protected] | 516-367-8455

Funding

National Institutes of Health, Goldring Family Foundation, Cancer Research UK, UKRI Medical Research Council, Wellcome Trust, European Research Council

Citation

Stillman, B., et al., 鈥淢echanisms for licensing origins of DNA replication in eukaryotic cells鈥�, Nature Structural & Molecular Biology, June 30, 2025. DOI: