Cochlear Amplification

Cochlear Amplification and Prestin

Cochlear amplification allows us detect incredibly low decibel noises (e.g., pin drop). This process is thought to be achieved through somatic motility that is driven by the protein prestin. Prestin was discovered in 2000 and since then, there has been intensive research into the piezoelectrical properties of this unique protein.

In 2004, I started my graduate work examining the unique properties of this intriguing protein.

 

Prestin Structure-Function

Proteins are often defined by their structure-function relationship. This allows us to gain insight into protein function by examining proteins with similar function and imputing similar function. Based on bioinformatic sequence analysis, my dissertation work discovered that prestin was defined by two domains: 1) SulP domain that formed a transmembrane channel and 2) a STAS domain which formed an intracellular domain. Based on this work, I was able to find similar strutures with known function and hypothesized that prestin formed a tetramer and that the SulP domain was a modified channel transporter and the STAS operated to modify SulP transporter function.

 

Prestin Tetramerization

Quaternary structures of proteins give insight to the function structure of the protein and, based upon the bioinformatic analysis of its structure-function relationship, I had hypothesized that prestin formed a tetramer. To test this work, I developed super-resolution microscopy techniques using inherited properties of fluorescent molecules (i.e., FRET, FLIM and photobleaching). I developed several constructs that encoded prestin conjugated proteins and used them to empirically establish that prestin did form homo-oligomers with the most likely structure being a tetramer.