Connexin 43
Also called: Cx43
What it means
Connexin 43 is a protein that builds tiny tunnels, called gap junctions, letting bone cells pass signals directly to each other.
This cell-to-cell communication system helps your bone cells coordinate as a network, which is part of how your bones sense and respond to what you do.
Connexin 43 is the protein that forms the tiny tunnels, called gap junctions, connecting the long arms (dendrites) of your osteocytes to one another. These direct connections let ions, small molecules, and electrical signals pass straight from one bone cell to the next, without having to go through the bloodstream first.
This matters because it's part of how bone cells talk to each other quickly. When one osteocyte senses a force, it can use these Connexin 43 tunnels to alert hundreds of neighboring cells within milliseconds. That's how a single loading event, like a step or a push, can trigger a coordinated response across a whole region of bone rather than just one isolated spot.
How sure is this?
Graded Established Science: Supported by broad scientific consensus and decades of research. Read each study with its grade in mind. One study is a piece of the picture, not the whole of it.
Connexin 43 builds tiny tunnels letting bone cells communicate directly, helping bones sense and respond to activity.
Where this leads
WordConnexin 43 builds these tunnels, so you might want to see exactly what gap junctions do for bone cell communication.
Where the Academy teaches it
This page is the short version. The lessons teach it in full, with the context around it and a quiz to lock it in.
Related words
Osteocytes are the most common bone cells. They used to be bone-builders but got trapped inside bone tissue, where…
Gap junctions are direct tunnels between bone cells that let them share signals instantly, so one cell sensing force…
Mechanotransduction is how bone cells sense physical force and turn it into chemical signals that tell bone to adapt.
Canaliculi are microscopic channels in bone that connect bone cells together and let fluid flow past them, helping…
The lacunar-canalicular system is a network of tiny spaces and channels in bone where fluid moves when bone is…
Osteocyte apoptosis is the programmed death of bone-sensing cells, which can trigger local bone breakdown through…
Education only, not medical advice. Decisions about tests, medications and treatment belong with your own doctor. OsteoStrong does not diagnose, treat or cure any disease.
