Related Experiment Video
Updated: Jul 14, 2026
03:52
Posterior Semicircular Canal Approach for Inner Ear Gene Delivery in Neonatal Mouse
Published on: March 2, 2018
Ion channel gene expression in the inner ear.
Irene S Gabashvili1, Bernd H A Sokolowski, Cynthia C Morton
1Hewlett-Packard Labs, 1501 Page Mill Road, Palo Alto, CA 94304, USA. igabashvili@yahoo.com
Summary
Researchers identified over a third of the ion channel genome expressed in the inner ear using computational tools. Most ion channel gene variants are not unique to the inner ear, and many splice variants remain unannotated.
Area of Science:
- Genomics
- Neuroscience
- Molecular Biology
Background:
- The complete ion channel genome and transcriptome remain incompletely defined.
- Assessing the full spectrum of ion channel gene expression in the inner ear is challenging.
Purpose of the Study:
- To computationally identify and analyze genes coding for ion channels expressed in the inner ear.
- To assess the coverage of the inner ear ion channelome using expressed sequence tags (ESTs).
Main Methods:
- High-throughput computational analysis of over 100,000 ESTs from various inner ear cDNA libraries.
- Mapping ESTs from human, mouse, zebrafish, and rat inner ear tissues to their respective genomes.
- Comparison with other gene expression measurement techniques.
Main Results:
- At least one-third of the ion channel genome is expressed in the inner ear, with highest expression in hair cell-enriched tissues.
- Most ion channel genes produce similar alternative transcripts across species; no variants are unique to the inner ear.
- Many splice variants are yet to be annotated, and current methods have limitations in providing complete coverage.
Conclusions:
- High-throughput computational analysis provides valuable insights into the inner ear ion channelome.
- Incomplete gene annotations and data limitations hinder comprehensive analysis and inter-species comparisons.
- Further research is needed to fully characterize the inner ear ion channelome.
Related Concept Videos
01:22Hair Cells
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
01:13The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
01:21G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
01:16Anatomy of the Ear
Auditory sensation, commonly called hearing, involves the transformation of sonic waves into neural impulses facilitated by the structures of the auditory organ. The prominent, flesh-like structure on the side of the head, called the auricle, directs sound waves towards the auditory canal. The auricle is often mislabeled as the pinna, a term more aligned with mobile structures like a feline's external ear. The auditory canal penetrates the cranium via the external auditory meatus of the...
01:15Auditory Pathway
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
01:19Ion Channels
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...
Ion channels are specialized integral membrane proteins on the plasma membrane that allow specific...