The mammalian cochlea is sophisticated in its function and highly organized structure. Although the anatomy of this sense organ has been well documented, molecular mechanisms underlying development have remained elusive. Information generated from mutant knockout mice recent years increased our understanding cochlear physiology. This article discusses factors important for inner ear summarizes phenotypes mice, particularly Otx Otx2 . We also present data on gross mouse cochlea.

The response regulator RpaB (regulator of phycobilisome associated B), part an essential two-component system conserved in cyanobacteria that responds to multiple environmental signals, has recently been implicated the control cell dimensions and circadian rhythms gene expression model cyanobacterium Synechococcus elongatus PCC 7942. However, little is known molecular mechanisms underlie functions. In this study we show regulation phenotypes by intimately connected with activity RpaA A),...

Gbx2 is a homeobox-containing transcription factor that related to unplugged in Drosophila. In mice, and Otx2 negatively regulate each other establish the mid-hindbrain boundary neural tube. Here, we show required for development of mouse inner ear. Absence endolymphatic duct swelling membranous labyrinth are common features Gbx2-/- ears. More severe mutant phenotypes include absence anterior posterior semicircular canals, malformed saccule cochlear duct. However, formation lateral canal its...

NblS, the most conserved histidine kinase in cyanobacteria, regulates photosynthesis and acclimatization to a variety of environmental conditions. We used silico, vivo vitro approaches identify RpaB SrrA as cognate response regulators NblS characterize relevant interactions between components this signalling system. While genetic analysis showed importance phosphorylation branch for culture viability Synechococcus elongatus PCC 7942, assays indicated strong preference phosphorylate SrrA....

Synechococcus elongatus PCC 7942 is a paradigmatic model organism for nitrogen regulation in cyanobacteria. Expression of genes involved assimilation positively regulated by the 2-oxoglutarate receptor and global transcriptional regulator NtcA. Maximal activation requires subsequent binding co-activator PipX. PII, protein found all three domains life as an integrator signals carbon balance, binds to PipX counteract NtcA activity at low levels. PII-PipX complexes can also bind PlmA, whose...

Yeast two-hybrid approaches, which are based on fusion proteins that must co-localise to the nucleus reconstitute transcriptional activity of GAL4, have greatly contributed our understanding nitrogen interaction network cyanobacteria, main hubs trimeric PII and monomeric PipX regulators. The bacterial system, reconstitution in E. coli cytoplasm adenylate cyclase Bordetella pertussis, should provide a relatively faster presumably more physiological assay for cyanobacterial than yeast system....

Cyanobacteria respond to environmental stress conditions by adjusting its photosynthesis machinery. When subjected nutrient and high light stress, Synechococcus sp. PCC 7942 other non-diazotrophic cyanobacteria degrade their phycobilisome, the light-harvesting complexes for photosynthesis. Phycobilisome degradation requires convergence of multiple signals onto nblA gene. Despite considerable efforts identify regulatory proteins involved in acclimation responses, signal transduction...

Photosynthetic organisms must cope with environmental challenges, like those imposed by the succession of days and nights or sudden changes in light intensities, that trigger global gene expression metabolism. The photosynthesis machinery is particularly susceptible to adaptation them often involves redox-sensing proteins are targets reactive oxygen species generated activity. Here we show EngA, an essential GTPase ribosome-assembly protein involved ribosome biogenesis bacteria chloroplasts,...

Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to the challenges imposed by succession of days and nights. Two conserved cyanobacterial proteins, PII PipX, function as hubs nitrogen interaction network, forming complexes with a variety diverse targets. While proteins are found in all three domains life integrators signals carbon balance, PipX unique cyanobacteria, where they provide mechanistic link between signalling control...

Summary Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to important environmental challenges, like those imposed by the succession of days and nights. Not surprisingly, certain regulatory proteins are found exclusively in this phylum. One these unique factors, PipX, provides a mechanistic link between signals carbon/nitrogen energy, transduced signalling protein PII, control gene expression global nitrogen regulator NtcA. Here...

Cyanobacteria, microorganisms performing oxygenic photosynthesis, must adapt their metabolic processes to environmental challenges such as day and night changes. PipX, a unique regulatory protein from cyanobacteria, provides mechanistic link between the signalling PII, widely conserved (in bacteria plants) transducer of carbon/nitrogen/energy richness, transcriptional regulator NtcA, which controls large regulon involved in nitrogen assimilation. PipX is also translational regulation through...

Summary: Purpose: This study was performed to evaluate whether audiogenic seizures, in a strain of genetically epilepsy‐prone hamsters (GPG/Vall), might be associated with morphologic alterations the cochlea and auditory brainstem. In addition, we used parvalbumin as marker neurons high levels activity examine changes within neurons. Methods : Cochlear histology well immunohistochemistry were assess possible abnormalities GPG/Vall hamster. Densitometry also quantify immunostaining fibers...

Cyanobacteria, phototrophic organisms performing oxygenic photosynthesis, must adapt their metabolic processes to important environmental challenges, like those imposed by the succession of days and nights. Not surprisingly, certain regulatory proteins are found exclusively in this phylum. One these unique proteins, PipX, provides a mechanistic link between signals carbon/nitrogen energy, transduced signaling protein PII, control gene expression global nitrogen regulator NtcA. required for...

Yeast two-hybrid approaches, which are based on fusion proteins that must co-localise to the nucleus reconstitute transcriptional activity of GAL4 have greatly contributed understand nitrogen interaction network cyanobacteria, whose main hubs trimeric PII and monomeric PipX regulators. The bacterial system, reconstitution in E. coli cytoplasm adenylate cyclase Bordetella pertussis, should provide a relatively faster presumably more physiological assay for cyanobacterial than yeast system....

Cyanobacteria, microorganisms performing oxygenic photosynthesis, must adapt their metabolic processes to environmental challenges such as day and night changes. PipX, a unique regulatory protein from cyanobacteria provides mechanistic link between signalling PII, widely conserved (in bacteria plants) transducer of carbon/nitrogen/energy richness, the transcriptional regulator NtcA, which controls large regulon involved in nitrogen assimilation. PipX is also translational regulation by...

During development, different epithelial cells in the mouse cochlea express cell surface glycoconjugates, which may reflect membrane specialization. Some of lectins tested this study (SBA, succ-WGA, and PSA) labeled sensory around birth. Other (WGA, Con A, RCA-II, PHA-E) surfaces cells, particularly stereocilia, from early stages development (gestation day (GD) 16) through 21 days after These be adhesion molecules needed to attach newly forming tectorial (TM) stereocilia. Lectin staining...

Abstract Congenital hypothyroidism induces developmental abnormalities in the auditory receptor, causing deafness due to a poor development of outer hair cells (OHCs) and lack synaptogenesis between these olivocochlear axons. This efferent innervation is formed by two separate systems: lateral system, which originates superior olive (LSO) reaches inner cells; medial ventral nucleus trapezoid body (VNTB) innervates OHCs. A previous study carried out our laboratory showed that congenitally...