Department of Cell and Molecular Biology

A new publication in Nature Communications from researchers at The Department of Cell and Molecular Biology solves a long-standing problem by establishing a system that allows site-specific protein degradation within mitochondria, the cellular hubs for energy production and metabolism.

Understanding how cells work often requires manipulating protein function. Methods used to do this usually cause total ablation of protein function and cannot provide information about their specific roles within different cellular compartments. This is especially challenging for organelles like mitochondria. Addressing this, the researchers present, for the first time, a technique for targeted protein degradation within the mitochondria of yeast and human cells. They have also devised a way to control the induction of degradation, thereby allowing time-resolved analysis.

Researchers from Karolinska Institutet and Charles University studying liver fibrosis have made an exciting new discovery, now published in EMBO Molecular Medicine. Their latest findings could pave the way for innovative approaches to treating this challenging condition.

What influences the extent of scar tissue, or fibrosis, that develops in the liver when people suffer from liver disease? While a small amount of fibrosis is a normal part of the healing process, excessive fibrosis can occur, leading to complications and, ultimately, liver failure. Understanding the mechanisms that drive this escalation is essential in the fight against liver disease.

Researchers from Karolinska Institutet have in collaboration with the University of Eastern Finland and Lund University a new publication in Genome Biology, demonstrated that targeting cell cycle and cell fate regulatory programs blocks non-genetic cancer evolution in acute lymphoblastic leukemia.

Findings from Olle Sangfelt's group at the Department of Cell and Molecular Biology in collaboration with the group of Merja Heinäniemi, the University of Eastern Finland and Anna Hagström-Andersson, Lund University shed light on the intricate connections between gene regulation, cell cycle control, and cell fate, providing a rationale for combining WEE1 inhibitors with other targeted therapies to enhance treatment efficacy while minimizing side effects.

A new publication in Molecular Cell presents a collaborative study within the framework of the UTokyo-KI LINK program, headed by Camilla Björkegren from The Department of Cell and Molecular Biology at Karolinska Institutet, Kristian Jeppsson and Katsuhiko Shirahige from The University of Tokyo.

The study shows that a protein complex named Smc5/6 binds DNA structures called positive supercoils. These form when the chromosomal DNA double helix folds onto itself due to overtwisting caused by transcription, which is the first step in gene expression. The study presents in vivo data indicating that Smc5/6 binds to the base of chromosome loops in regions that contain high levels of transcription-induced positive supercoils.