Usher 1C
Encyclopedia
Usher 1C is a human
gene
. Recessive allele
s of this gene are responsible for type 1C Usher syndrome
and nonsyndromic deafness
.
The official name of the gene Usher 1C is “Usher syndrome
1C (autosomal recessive, severe).”
USH1C is the gene's official symbol. The USH1C gene is also known by other names, listed in the Other Names section, below.
called harmonin. Harmonin has the ability to bind to many other proteins in cell membranes and coordinates their activities. Harmonin sometimes acts as a bridge linking proteins in the cell membrane to those in the cytoskeleton
, the internal framework that supports the cell
.
Research suggests that harmonin plays a role in the development
and maintenance of hairlike projections called stereocilia
. Stereocilia line the inner ear
and bend in response to sound
waves. This bending motion is critical for converting sound waves to nerve
impulses, an essential process for normal hearing
. In the inner ear, protein complexes organized by harmonin probably act as connectors that link stereocilia into a bundle. This protein complex likely helps regulate the transmission of sound waves.
Harmonin is also made in specialized cells called photoreceptors. These cells detect and transfer light energy to the light-sensitive tissue at the back of the eye
(the retina
). The function of the harmonin-protein complex in the retina is not well understood, but it is thought to be important in the development and function of photoreceptor cells.
Human
Humans are the only living species in the Homo genus...
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...
. Recessive allele
Allele
An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...
s of this gene are responsible for type 1C Usher syndrome
Usher syndrome
Usher syndrome is a relatively rare genetic disorder that is a leading cause of deafblindness and that is associated with a mutation in any one of 10 genes. Other names for Usher syndrome include Hallgren syndrome, Usher-Hallgren syndrome, rp-dysacusis syndrome and dystrophia retinae dysacusis...
and nonsyndromic deafness
Nonsyndromic 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....
.
The official name of the gene Usher 1C is “Usher syndrome
Usher syndrome
Usher syndrome is a relatively rare genetic disorder that is a leading cause of deafblindness and that is associated with a mutation in any one of 10 genes. Other names for Usher syndrome include Hallgren syndrome, Usher-Hallgren syndrome, rp-dysacusis syndrome and dystrophia retinae dysacusis...
1C (autosomal recessive, severe).”
USH1C is the gene's official symbol. The USH1C gene is also known by other names, listed in the Other Names section, below.
Function
The USH1C gene carries the instructions for the production of a proteinProtein
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...
called harmonin. Harmonin has the ability to bind to many other proteins in cell membranes and coordinates their activities. Harmonin sometimes acts as a bridge linking proteins in the cell membrane to those in the cytoskeleton
Cytoskeleton
The cytoskeleton is a cellular "scaffolding" or "skeleton" contained within a cell's cytoplasm and is made out of protein. The cytoskeleton is present in all cells; it was once thought to be unique to eukaryotes, but recent research has identified the prokaryotic cytoskeleton...
, the internal framework that supports the cell
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....
.
Research suggests that harmonin plays a role in the development
Morphogenesis
Morphogenesis , is the biological process that causes an organism to develop its shape...
and maintenance of hairlike projections called stereocilia
Stereocilia
In the inner ear, stereocilia are the mechanosensing organelles of hair cells, which respond to fluid motion in numerous types of animals for various functions, including hearing and balance. They are about 10–50 micrometers in length and share some similar features of microvilli...
. Stereocilia line the inner ear
Inner ear
The inner ear is the innermost part of the vertebrate ear. In mammals, it consists of the bony labyrinth, a hollow cavity in the temporal bone of the skull with a system of passages comprising two main functional parts:...
and bend in response to sound
Sound
Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.-Propagation of...
waves. This bending motion is critical for converting sound waves to nerve
Nerve
A peripheral nerve, or simply nerve, is an enclosed, cable-like bundle of peripheral axons . A nerve provides a common pathway for the electrochemical nerve impulses that are transmitted along each of the axons. Nerves are found only in the peripheral nervous system...
impulses, an essential process for normal hearing
Hearing (sense)
Hearing is the ability to perceive sound by detecting vibrations through an organ such as the ear. It is one of the traditional five senses...
. In the inner ear, protein complexes organized by harmonin probably act as connectors that link stereocilia into a bundle. This protein complex likely helps regulate the transmission of sound waves.
Harmonin is also made in specialized cells called photoreceptors. These cells detect and transfer light energy to the light-sensitive tissue at the back of the eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
(the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
). The function of the harmonin-protein complex in the retina is not well understood, but it is thought to be important in the development and function of photoreceptor cells.
Other names
- AIE-75
- DFNB18
- HARMONIN
- NY-CO-37
- NY-CO-38
- PDZ-45
- PDZ-73
- PDZ73
- USH1C_HUMAN
- Usher syndrome 1C protein