A groundbreaking study has shed new light on the fundamental mechanisms governing microtubule growth within cells. Researchers from Queen Mary University of London and the University of Dundee have made a significant breakthrough by discovering that the ability of tubulin proteins at microtubule ends to connect with each other sideways determines whether a microtubule elongates or shortens.

Microtubules are crucial protein structures that form the internal skeleton of cells, providing structural support and generating dynamic forces that push and pull. These tiny filaments constantly assemble and disassemble by adding or removing tubulin building blocks at their ends. However, the precise rules dictating whether a microtubule grows or shrinks have long remained a mystery due to the complexity and miniature size of their ends.

The collaborative research team has cracked part of this code using advanced computer simulations coupled with innovative imaging techniques. This interdisciplinary approach has allowed them to address this complex biological question from a fresh perspective, bridging physics and biology.

Dr. Vladimir Volkov, co-lead author from Queen Mary University of London, explained the significance of their findings: “Understanding how microtubules grow and shorten is very important – this mechanism underlies division and motility of all our cells. Our results will inform future biomedical research, particularly in areas related to cell growth and cancer.”

Dr. Maxim Igaev, co-lead author from the University of Dundee, highlighted the power of their interdisciplinary approach: “Bridging physics and biology has allowed us to address this complex biological question from a fresh perspective. This synergy not only enriches both fields but also paves the way for discoveries that neither discipline could achieve in isolation.”

This exciting research deepens our understanding of fundamental cellular processes and opens potential new avenues for biomedical research, particularly in areas concerning cell proliferation and the development of treatments for diseases like cancer.

The inner workings of cells have long been a subject of scientific inquiry, and researchers at Stockholm University’s SciLifeLab have made a groundbreaking discovery. A team led by Professor David Drew has uncovered how the cell’s main energy currency, ATP (adenosine triphosphate), is transported into the endoplasmic reticulum (ER), the cell’s primary “shipping port” for protein and lipid packaging.

The ER plays a vital role in checking protein quality and facilitating their transport within the cell. For these processes to occur efficiently, energy in the form of ATP is required. Despite decades of research on ER function, the question of how ATP reaches the inside of the ER had remained unclear – until now.

Professor Drew’s team confirmed that the transporter protein SLC35B1 is the key gateway for ATP entry into the ER. This discovery was made possible through a combination of biochemical and structural validation, including the use of cryo-electron microscopy (cryo-EM) to visualize SLC35B1 in multiple conformations.

The study published in Nature reveals the first structural and mechanistic insight into how ATP enters the endoplasmic reticulum using the transporter protein SLC35B1. The ER is the cell’s main “shipping port” that packages proteins and lipids, checks their quality, and facilitates their transport within the cell.

“This discovery has broad implications for human health,” says Professor Drew. “Disrupted ER activity is linked to diseases such as type 2 diabetes, cancer, and neurodegenerative disorders, where ER stress and protein misfolding play central roles.” With a detailed molecular blueprint now available, SLC35B1 presents a promising target for future drug development.

Understanding how energy is delivered into the ER gives researchers powerful new ways to tackle these diseases. Modulating SLC35B1 activity could become a new strategy for restoring ER balance in disease states.

Professor Drew’s team has already begun screening for small molecules that modulate SLC35B1 function, with the goal of developing targeted therapies to either enhance or inhibit ATP transport when needed. This research holds great promise for improving human health and unlocking new therapeutic opportunities for diseases linked to ER dysfunction.

Here is the rewritten article:

The presence of dead individuals has profound effects across species. From insects like bees and ants removing dead members from their hive to keep the nest clean, to the aversion humans have for decaying bodies, it’s clear that death elicits strong responses. Research at the University of Michigan has shed new light on this phenomenon in the roundworm C. elegans.

In a study published in Cell Reports, researchers discovered that when exposed to dead counterparts, C. elegans experience altered fertility and lifespan. The presence of decedents led to quick reproduction and shortened lifespans in the worms. This response is remarkable considering the worms’ inability to see.

“We were fascinated by this unique opportunity to explore what drives the reaction of C. elegans to a dead conscript,” said Matthias Truttmann, Ph.D., senior author on the paper. His lab studies protein function and aging, making C. elegans an ideal model for studying life extension due to their relatively short lifespans.

The researchers observed that when worms were placed near deceased counterparts, they would move as far away as possible. They hypothesized that there might be a universal death signal emitted by corpses. To test this, they introduced either worm corpses or fluid from the broken-down cells of worm corpses to different feeding areas on a plate. The results showed strong avoidance behavior in C. elegans for both.

Furthermore, the team found that death perception led to reduced fitness in exposed worms and a short-term increase in egg laying. They then systematically tested the worms’ sensory neurons to determine which were necessary for the perception of death. Two olfactory information-responding neurons, AWB and ASH, were identified as key players.

The researchers discovered two metabolites, AMP and histidine, which are normally found inside cells, serve as the death cues for C. elegans. These intracellular metabolites indicate that a cell has died or broken open, signaling something has gone wrong. The presence of these metabolites could very well be an evolutionarily maintained signal of death.

Truttmann points to recent findings in humans where cells undergoing apoptosis release metabolites leading to transcriptional changes in neighboring tissue. Further research is needed to understand how the detection of this signal translates into altered health and behavior.