May 16, 2024

Powerful New Tool Can Peer Into the Vast Genetic Library Inside of Your Cells

Led by previous Guttman laboratory graduate student Sofia Quinodoz (PhD 20)– now a Hanna Gray postdoctoral fellow at Princeton University– the group discovered that molecules of non-coding RNA are accountable for establishing “compartments” within the nucleus and shepherding in essential particles to exact regions in the genome. Noncoding RNA are particles that do not encode for proteins, and instead have a variety of functions that are typically still mysterious to biologists. In the library example, non-coding RNA molecules serve as the “racks” that arrange different groups of genes and the equipment that interacts with them.
Understanding how hereditary material is arranged spatially is an important part of understanding the basic functions of life. Dysfunction within the nucleus is a hallmark of numerous illness, including cancer, neurodegenerative disorders, and others.
The research study was made possible by a powerful tool developed in the Guttman lab that enables comprehensive views of the RNA world, called RD-SPRITE (RNA and DNA Split-Pool Recognition of Interactions by Tag Extension). In essence, RD-SPRITE works by tagging particles of RNA and DNA with small distinct barcodes based upon their locations; examining the barcodes can then tell you which molecules were at which positions within the cell.
” This tool is something Ive imagined considering that I was a graduate trainee. Its impressive that Sofia had the ability to make this occur,” says Guttman. “It changes what we can take a look at in the RNA world. Its like establishing a new microscope; you can start looking at things you could never ever see before. This discovery about RNA and organization is the idea of the iceberg in terms of what we are able to begin discovering in these data.”
The group prepares to use RD-SPRITE to compare the spatial company of the nucleus between healthy cells and disease cell types, to comprehend how gene expression and the physical structure of the nucleus may be impacted in disease states.
Recommendation: “RNA promotes the formation of spatial compartments in the nucleus” by Sofia A. Quinodoz, Joanna W. Jachowicz, Prashant Bhat, Noah Ollikainen, Abhik K. Banerjee, Isabel N. Goronzy, Mario R. Blanco, Peter Chovanec, Amy Chow, Yolanda Markaki, Jasmine Thai, Kathrin Plath and Mitchell Guttman, 4 November 2021, Cell.DOI: 10.1016/ j.cell.2021.10.014.
The paper is entitled “RNA promotes the formation of spatial compartments in the nucleus.” Sofia Quinodoz is the papers first author in addition to co-second authors Caltech postdoctoral scholar Joanna Jachowicz, graduate trainee Prashant Bhat, and former postdoctoral scholar Noah Ollikainen. In addition to Guttman, other coauthors include previous graduate trainee Abhik Banerjee, graduate student Isabel Goronzy, research researcher Mario Blanco, former postdoctoral scholar Peter Chovanec, senior research study scientist Amy Chow, Yolanda Markaki of UCLA, previous research study specialist assistant Jasmine Thai, and Kathrin Plath of UCLA. Funding was supplied by the Howard Hughes Medical Institute, the National Science Foundation, the National Institutes of Health, the UCLA-Caltech Medical Scientist Training Program, the American Cancer Society, the Division of Biology and Biological Engineering at Caltech, the National Heart Lung and Blood Institute, and the USC MD/PhD program.

DNA and associated cellular equipment is collected and arranged by specific non-coding RNAs, each area shown in a different colored jellybean-shape in this design. Credit: Courtesy of Inna-Marie Strazhnik
There are genes which contain details to develop a brain cell, a skin cell, a white blood cell, and so on. The ability to control gene expression– in other words, the cells capability to turn different constellations of genes on or off– is the basis of why different cells (such as a muscle cell or a brain cell) have various types and functions.
For any library to be helpful to a reader, it requires to be arranged in a quickly searchable way. For example, all the books referring to world history might be on one shelf, whereas the cookbooks might be in a completely various area of the library. In a cellular nucleus, there is over six feet of hereditary material loaded into a space 50 times smaller sized than the width of a human hair. How is the “library” in the nucleus organized? When a cell requires to control certain genes, how does the cellular machinery find the right ones among 20,000 others?
A new paper from the laboratory of Mitchell Guttman, professor of biology, uses an effective new tool that can peer into the world of the cells hereditary material (DNA and RNA) in order to find answers to these questions.

The ability to regulate gene expression– in other words, the cells capability to turn various constellations of genes on or off– is the basis of why various cells (such as a muscle cell or a brain cell) have various forms and functions.
Led by previous Guttman lab graduate student Sofia Quinodoz (PhD 20)– now a Hanna Gray postdoctoral fellow at Princeton University– the team discovered that particles of non-coding RNA are accountable for developing “compartments” within the nucleus and shepherding in essential molecules to accurate areas in the genome. Noncoding RNA are molecules that do not encode for proteins, and rather have a selection of functions that are typically still mysterious to biologists. In the library analogy, non-coding RNA molecules act as the “shelves” that organize various groups of genes and the machinery that communicates with them.
“It changes what we can look at in the RNA world.