More Than Just a Powerhouse
Image of mitochondria (grey) and cell nucleus (blue). Artist rendition of the mitochondria as a cartoon superhero. Cell photo taken by Amy Bounds and cartoon made by Amy Bounds.
The identity of the superhero of biology has recently been under fire.
Scientists are calling the superhero’s catch phrase “out of date” and “expired”. The discussions surrounding this superhero's identity are not due to its lackluster job. Quite the opposite: this powerhouse has been taking on more tasks than just producing energy. The world-renowned cellular compartment in question is none other than the mitochondria!
The mitochondria, otherwise known as the “powerhouse of the cell”, are famous for being the compartments within a cell that produce energy. In a 2022 scientific review, scientists Martin Picard and Orian Shirihai called for a “re-branding” of the mitochondria. They suggest the phrase “powerhouse of the cell” minimizes the mitochondria’s role to a simple workhorse that just produces energy, instead of highlighting the mitochondria’s wide range of functions. The scientists then advocated for a new catch phrase, “mitochondria are the processors of the cell or more precisely as the mitochondrial information processing system (MIPS)”.
This re-brand has failed to gain traction in the public sphere. Could this be because the new catch phrase is a little bit of a mouthful or that the simplified “powerhouse of the cell” phrase is deeply rooted in our education system?
Maybe the mitochondria deserves not only a new title, but also a makeover.
Over the past twenty-five years, the number of papers published about the mitochondria has skyrocketed, making the mitochondria the most talked about cellular compartment. All this new research has opened scientists’ eyes to the diverse roles of this beautifully complex compartment. Picard and Shirihai highlight the many roles of the mitochondria including the role as a communicator between different compartments in a cell and their ability to respond to stress.
It may be surprising that these tiny bean-shaped cellular compartments handle all these critical functions. As it turns out, even this typical illustration of the mitochondria is misleading.
There are hundreds of mitochondria in a cell that can actively fuse with each other to make a large, dynamic network. This allows them to share resources and makes sure the cell has plenty of nutrients. The connected network can also divide, and the mitochondria can separate when the cell needs to respond to the numerous stress signals during a cell’s lifetime. Growing evidence has also implicated the disruption of this dynamic network in a variety of diseases. The mitochondria’s ability to constantly fuse and divide allows them to adapt to the rapidly changing cell environment to ensure all their different jobs are completed.
Far from a singular bean-shaped superhero, it is this constantly adapting network that allows the mitochondria to take on the role as the great communicator and processor. To create change in our perceptions of the role of mitochondria in the cell, we also need to change how we visualize the mitochondria.
Mitochondrial form must fuel its function.
To fully honor how the mitochondria is constantly shaping cellular success, we must grant the mitochondria a new title: the cell’s legion of shapeshifters.
References
1. Picard M, Shirihai OS. Mitochondrial signal transduction. Cell Metab. 34, 11 (2022).
2. Picard M, et al. The Rise of Mitochondria in Medicine. Mitochondrion. 30, 105-1116 (2017).
Amy Bounds is a Biochemistry PhD graduate student at the University of Washington where she works in Suzanne Hoppins’ lab. The Hoppins’ lab studies how the mitochondria change shape to complete different tasks in the cell. Amy’s research focuses on understanding the function of protein that may be involved in regulating how and when the mitochondria change their shape.