Prestin
Encyclopedia
Prestin is a protein
that in humans is encoded by the SLC26A5 (solute carrier family 26, member 5) gene
.
Prestin is the motor protein of the outer hair cells
of the inner ear of the mammal
ian cochlea
. It is highly expressed in the outer hair cells, and is not expressed in the nonmotile inner hair cells. Immunolocalization
shows prestin is expressed in the lateral plasma membrane of the outer hair cells, the region where electromotility occurs. The expression pattern correlates with the appearance of outer hair cell electromotility.
and is essential in auditory processing. Intracellular anions are thought to act as extrinsic voltage sensors, which bind to this protein and trigger the conformational changes required for rapid length changes in OHCs. Not surprisingly the keen echolocation
in bats and dolphins is driven by prestin.
Prestin (mol. wt. 80 kDa
) is a member of a distinct family of anion transporters, SLC26. Members of this family are structurally
well conserved and can mediate the electroneutral exchange of chloride
and carbonate
across the plasma membrane of mammalian cells, two anions found to be essential for outer hair cell motility. Unlike the classical, enzymatically driven motors, the function of this new type of motor is based on direct voltage-to-displacement conversion. It acts several orders of magnitude faster than cellular motor proteins. A targeted gene disruption
strategy of prestin showed a >100-fold (or 40 dB) loss of auditory sensitivity.
.
The prestin molecule was patented
by its discoverers in 2003.
.
Protein
Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...
that in humans is encoded by the SLC26A5 (solute carrier family 26, member 5) gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Prestin is the motor protein of the outer hair cells
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
of the inner ear of the mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
ian cochlea
Cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
. It is highly expressed in the outer hair cells, and is not expressed in the nonmotile inner hair cells. Immunolocalization
Immunohistochemistry
Immunohistochemistry or IHC refers to the process of detecting antigens in cells of a tissue section by exploiting the principle of antibodies binding specifically to antigens in biological tissues. IHC takes its name from the roots "immuno," in reference to antibodies used in the procedure, and...
shows prestin is expressed in the lateral plasma membrane of the outer hair cells, the region where electromotility occurs. The expression pattern correlates with the appearance of outer hair cell electromotility.
Function
Prestin is specifically expressed in outer hair cells (OHCs) of the cochleaCochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
and is essential in auditory processing. Intracellular anions are thought to act as extrinsic voltage sensors, which bind to this protein and trigger the conformational changes required for rapid length changes in OHCs. Not surprisingly the keen echolocation
Echolocation
Echolocation may refer to:* Acoustic location, the general use of sound to locate objects* Animal echolocation, non-human animals emitting sound waves and listening to the echo in order to locate objects or navigate...
in bats and dolphins is driven by prestin.
Prestin (mol. wt. 80 kDa
Atomic mass unit
The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...
) is a member of a distinct family of anion transporters, SLC26. Members of this family are structurally
Protein structure
Proteins are an important class of biological macromolecules present in all organisms. Proteins are polymers of amino acids. Classified by their physical size, proteins are nanoparticles . Each protein polymer – also known as a polypeptide – consists of a sequence formed from 20 possible L-α-amino...
well conserved and can mediate the electroneutral exchange of chloride
Chloride
The chloride ion is formed when the element chlorine, a halogen, picks up one electron to form an anion Cl−. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. The chloride ion, and its salts such as sodium chloride, are very soluble in water...
and carbonate
Carbonate
In chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....
across the plasma membrane of mammalian cells, two anions found to be essential for outer hair cell motility. Unlike the classical, enzymatically driven motors, the function of this new type of motor is based on direct voltage-to-displacement conversion. It acts several orders of magnitude faster than cellular motor proteins. A targeted gene disruption
Gene knockout
A gene knockout is a genetic technique in which one of an organism's genes is made inoperative . Also known as knockout organisms or simply knockouts, they are used in learning about a gene that has been sequenced, but which has an unknown or incompletely known function...
strategy of prestin showed a >100-fold (or 40 dB) loss of auditory sensitivity.
Discovery
Prestin was discovered by Peter Dallos' group in 2000 and named from the musical notation prestoPresto
-As a common word:* An incantation or interjection used by some stage magicians* A musical score marking indicating a fast tempo* An exclamation to mean: [to be completed] right away, instantly, i.e. "magically"-Places:*Presto, Bolivia...
.
The prestin molecule was patented
Biological patent
A biological patent is a patent relating to an invention or discovery in biology. It can be a composition of matter, a method for obtaining or using one or more thereof, or a product combining such things...
by its discoverers in 2003.
Clinical significance
Mutations in the SLC26A5 gene have been associated with non-syndromic hearing lossNonsyndromic deafness
Nonsyndromic deafness is hearing loss that is not associated with other signs and symptoms. In contrast, syndromic deafness involves hearing loss that occurs with abnormalities in other parts of the body....
.