Ashmore lecture Flashcards
Role of prestin overall
Makes the OHC work
What is the structure of prestin?
Dimer, membrane protein
Where is prestin found?
occupies most of the OHC lateral membrane
What is a tip link?
Connets one sterocilia to the one behind it.
2 Proteins markers of tip links
These transduce force derived from stereocilia displacement to opening of ion channel component of the MT complex
PCDH15
CDH23
What do OHC use Prestin for?
1.To change hair cell length
2.To generate force
3. To amplify cochlear mechanics
What is prestin known for
a low efficiency chloride carbonate antiporter
Genomic identity of prestin and expression in body
SLC26A5-expressed just in the OHC
what blocks prestin
aspirin
salicylate
How does prestin work as a molecular motor?
dependent on chloride (carbonate- can be transported too)
Depolarization (more positive inside the cell) → Prestin contracts, shortening the cell.
Hyperpolarization (more negative inside the cell) → Prestin expands, lengthening the cell.
Resting State: Prestin binds to intracellular chloride ions.
Voltage Change: When the cell depolarizes, chloride ions shift position, causing a conformational change in prestin.
Mechanical Response: This conformational change leads to the contraction or expansion of the OHC, modifying its length almost instantly
What is TMC-1?
Transmembrane channel-like protein 1- forms the pore of mechnosensory transduction channels in inner hair cells
