Lmx1a maintains proper neurogenic, sensory, and nonsensory domains in the mammalian inner ear
| Autor: | Soo Kyung Koo, Kathleen J. Millen, Jennifer K. Hill, Zheng Shi Lin, Chan Ho Hwang, Doris K. Wu |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
Fgf3
Membranous labyrinth LIM-Homeodomain Proteins Sensory system Cochlear duct Biology Article Epithelium Endolymphatic duct 03 medical and health sciences Mice 0302 clinical medicine medicine otorhinolaryngologic diseases Animals Inner ear Molecular Biology Spiral ganglion 030304 developmental biology Body Patterning Vestibular system Homeodomain Proteins 0303 health sciences Neurogenic fate LIM homeodomain Inner ear development Cell Biology Anatomy Cochlear Duct Mice Mutant Strains medicine.anatomical_structure Ear Inner Mutation Ectopic expression sense organs Vestibule Labyrinth Transcription factor Spiral Ganglion 030217 neurology & neurosurgery Developmental Biology Transcription Factors |
| Popis: | Lmx1a is a LIM homeodomain-containing transcription factor, which is required for the formation of multiple organs. Lmx1a is broadly expressed in early stages of the developing inner ear, but its expression is soon restricted to the non-sensory regions of the developing ear. In an Lmx1a functional null mutant, dreher (drJ/drJ), the inner ears lack a non-sensory structure, the endolymphatic duct, and the membranous labyrinth is poorly developed. These phenotypes are consistent with Lmx1a's role as a selector gene. More importantly, while all three primary fates of the inner ear – neural, sensory, and non-sensory – are specified in drJ/drJ, normal boundaries among these tissues are often violated. For example, the neurogenic domain of the ear epithelium, from which cells delaminate to form the cochleovestibular ganglion, is expanded. Within the neurogenic domain, the demarcation between the vestibular and auditory neurogenic domains is most likely disrupted as well, based on the increased numbers of vestibular neuroblasts and ectopic expression of Fgf3, which normally is associated specifically with the vestibular neurogenic region. Furthermore, aberrant and ectopic sensory organs are observed; most striking among these is vestibular-like hair cells located in the cochlear duct. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|