Right now, inside your body, trillions of tiny power stations are working at full capacity. They are called mitochondria, and almost everything you do — thinking, moving, even reading this article — runs on the energy they produce. This week, a team of scientists at the University of Ottawa announced that they have found something fundamental about how these power stations are built: a previously unknown protein that acts like a set of molecular pillars, holding the structure open and letting cells tune how much energy they make.
The protein is called SPRIZ — short for SPatial Regulator of the mitochondrial Intermembrane Zone — and the finding, published in the journal Science Advances on October 14, 2026, is being described as a potentially transformative piece of cell biology. It answers a question that sounds almost embarrassingly simple for something so important: how do cells control the shape of their own powerplants?
The Powerpacks Inside Every One of Your Cells
Most of us met mitochondria in a school biology class, usually with the nickname "the powerhouse of the cell." The nickname is overused, but the reality behind it is genuinely remarkable. Each mitochondrion is wrapped in not one but two membranes — an outer one and an inner one tucked inside it, folded into elaborate ridges called cristae. Between those two membranes lies a narrow gap, the intermembrane space.
That narrow gap is where the magic of energy production happens. The inner membrane houses the electron transport chain, a series of protein complexes that pump protons into the intermembrane space, building up a charge like a dam holds back water. The protons then flow back through an enzyme called ATP synthase, spinning it like a tiny turbine to manufacture ATP — the molecule that powers everything in the cell.
Here is the catch: the volume and geometry of that intermembrane space directly affect how well this machinery works. Think of it like a room in a factory — if the room collapses, the machines inside can't do their jobs. Biologists have long known that mitochondria change shape in response to stress, exercise, and disease, but nobody knew whether cells could actively, precisely adjust the spacing inside these organelles. The Ottawa team has now shown that they can — and that a single protein is the key.
SPRIZ: The Missing Pillar
SPRIZ, previously known only under the technical name CCDC127, turns out to be a rigid molecular tether that bridges the outer and inner mitochondrial membranes. Working like a column between two floors of a building, it holds the membranes apart at a controlled distance, locally setting the volume of the intermembrane space.
The study, led by University of Ottawa Faculty of Medicine investigator Marco Pellegrini, shows that this is not a passive structural detail. The volume of the intermembrane space is genetically controlled and adjustable. By deciding where the space widens or narrows within each mitochondrion, cells can actively shape the internal architecture of their powerpacks — and with it, tune how they function.
This matters because mitochondrial energy output is not one-size-fits-all. A muscle cell sprinting, a neuron firing, and a resting skin cell all have different energy demands. Mitochondria are known to remodel themselves under different conditions, and the discovery of SPRIZ suggests that cells have a dedicated molecular tool for reshaping the very room where energy chemistry happens.
How the Discovery Was Made
Discoveries like this are never the work of a single experiment. The Ottawa team combined four very different approaches to corner SPRIZ:
- Computer simulations of molecular movement, which modeled how the protein behaves between the two membranes at the atomic level;
- Genetics, testing what happens when the gene encoding SPRIZ is altered;
- Large-scale protein analysis, surveying which proteins sit where inside the mitochondria;
- Advanced imaging, including three-dimensional electron tomography, which produced nanometer-scale 3D reconstructions of the organelle's architecture.
Together, these approaches showed consistently that SPRIZ bridges the outer and inner membranes, forming a molecular pillar that holds the space open between them. Remove or alter it, and the spacing changes — and with it, the internal organization of the mitochondrion.
The human story behind the work is notable too. The first author of the study is Raman Shulinski, a graduate student, working alongside two undergraduates, Roman Loban and Victoria Caminiti. Their central role in a discovery of this weight is exactly the kind of thing that makes senior scientists take notice — and it did. The team also drew in collaborators across the uOttawa Faculty of Medicine, including mitochondrial metabolism specialists Mary-Ellen Harper, Eric Lee, Morgan Fullerton, and Yan Burelle, plus two prominent American scientists: mitochondrial biologist György Hajnóczky and evolutionary biologist Eugene Koonin.
This kind of collaboration is becoming a pattern in cutting-edge biology. Recent work on missing-link viruses that may rewrite the origin of life and on Sukunaarchaeum, the microbe that is redefining the limits of life similarly relied on stitching together genetics, computation, and imaging to answer questions no single method could solve alone.
An Evolutionary Twist Millions of Years Old
One of the most intriguing aspects of the paper is where SPRIZ is found in the tree of life. The protein is conserved across deuterostome animals — a large group that includes humans, other vertebrates, and sea stars. That conservation means the protein, and the architectural trick it performs, has been in use for hundreds of millions of years.
Evolutionary biologist Eugene Koonin's involvement hints at the deeper significance. As Pellegrini and colleagues point out, this finding places mitochondria in a larger evolutionary story: mitochondria did not adapt only by changing the molecular machinery of energy production. They also adapted by controlling the space in which that machinery operates.
That is a subtle but profound shift in perspective. For decades, most mitochondrial research has focused on the engines — the respiratory complexes, the ATP synthases, the transporters. The SPRIZ discovery says the room matters too, and that evolution invested in molecular pillars to engineer it. It is reminiscent of other recent findings that have forced scientists to redraw the map of basic biology, from the protist discovery that broke life's genetic code rules to the search for the smallest forms life can take.
Why This Matters for Medicine
The press announcement of the discovery points to a specific medical connection: Parkinson's disease. In Parkinson's, damaged mitochondria are not properly maintained or cleared away by the cell's recycling systems. If SPRIZ sets the architecture of the intermembrane space, then disruptions to that delicate spacing could be part of how mitochondria fail — and how failing mitochondria contribute to disease.
More broadly, the finding opens a new angle on every disease in which mitochondria fail to meet cells' energy needs: neurodegenerative disorders, muscle diseases, and some metabolic conditions. Before SPRIZ, researchers looking for the causes of mitochondrial failure mostly examined the protein machines of energy production. Now there is a new suspect to examine: the pillars that hold the factory open.
It is important to be honest about where this stands. This is a fundamental discovery, not a treatment. No drug based on SPRIZ exists, and none is likely soon. But nearly every therapy that works today began as a basic finding someone described as "just" understanding how something works. You cannot fix a machine you do not understand, and until this week, the spacing inside mitochondria was something biologists watched but could not explain.
What Comes Next
Pellegrini's lab is slated to move into the University of Ottawa's Advanced Medical Research Centre when it opens in 2027 — a 350,000-square-foot facility, the largest research investment in the university's history, with a dozen specialized core facilities. That move will give the team the kind of advanced imaging and analysis infrastructure that made this discovery possible in the first place.
The open questions are now clear, and they are exciting ones. Do cells actively raise and lower these pillars in real time — for example, when muscles need a burst of energy or when a cell is under stress? Are there diseases where the pillars are broken or misplaced? And could the same architectural trick show up in other double-membrane organelles, or in bacteria, mitochondria's ancient ancestors?
A decade ago, the idea that a single protein might serve as the cell's internal scaffolding for its power stations would have sounded speculative. Today it is a published, verified finding with a name, a structure, and a job description. The powerpacks inside our cells just got a little less mysterious — and a lot more interesting.