血液細胞の起源
Hello, everyone. SCIENSPOT is a podcast that shines a spotlight on the latest time tick technology from Japan. Your host is REN from SCIEN-TALK.
Today, let's talk about blood,
specifically, red blood cells which carry oxygen and platelets which stop bleeding.
Did you know that these two very different cells actually originated from the same parent cell?
I want to share some groundbreaking research from the Tohoku University that changes how we understand this process.
All blood cells come from stem cells in our bone marrow.
These stem cells eventually become a specific type of progenitor cell called an MEP.
megakaryocyte-erythroid
progenitor
I'm not confident in my pronunciation, but anyway,
think of the MEP as a traveler standing at a fork in the road.
One path leads to becoming a red blood cell, and the other path leads to becoming a megakaryocyte,
which produces platelets.
For a long time, scientists believed that genes or DNA blueprints were the main decision makers at this fork.
However, a research team led by Dr. Murakami and Professor Motohashi at the Tohoku University
has found a surprising new decision maker.
It's the mitochondria.
We usually learn in school that mitochondria are the powerhouse of the cell generating energy,
but this study shows that they do more
than that.
They actually decided the cell's fate. Here is how they figured this out.
These researchers used a special type of mouse with a mutation in the gene called CARS-2.
Without getting too bogged down in jargon,
this mutation caused the mitochondria to function poorly because they cannot produce a specific molecule called cysteine
ミトコンドリアの役割
persulfide,
which helps maintain energy metabolism.
When they looked at these mice, they found something strange.
The mouse were anathemic. The mouse were endemic. They had very few red blood cells,
but they had an increased number of platelets.
It wasn't a lack of iron. It was a problem with the cell's decision making process.
The researchers analyzed the MEP cells. These
travelers at the fork in the road.
They discovered that when mitochondria function is low,
the cells cannot choose the red blood cell path.
They deferred to the platelet path instead.
To prove this wasn't just a coincidence, they performed another experiment with normal mice.
They sorted the MEP cells into two groups, those with high mitochondrial content and
those with the low mitochondrial content. The result was clear. The cells with
ミトコンドリアの役割
the cells with lots of active mitochondria became red blood cells,
and the cells with fewer mitochondria became megakaryocytes, which is mean the platelets.
The term sells this concept mitochondrial navigation. It means the mitochondria are guiding the cell's lineage commitment.
Why does this matter?
This discovery opens new doors for medicine, some types of unexplained anemia,
might actually be caused by mitochondrial issues preventing cells from becoming red blood cells.
On the other hand, for diseases like
polycythemia,
where the body makes too many red blood cells,
doctors might able to treat it by targeting mitochondrial activity.
It's fascinating to think that the energy level inside the microscopic cell determines what it becomes.
That's all for today's SciencePod. This podcast is broadcast daily on weekday morning in both Japanese and English.
I'd love for you to listen to the podcast and post your thoughts with the hashtag SciencePod.
Thank you for listening and see you next time.
