Gene-expression analysis of hair cell regeneration in the zebrafish lateral line.
Deafness caused by the terminal loss of inner ear hair cells is one of the most common sensory diseases. However, nonmammalian animals (e.g., birds, amphibians, and fish) regenerate damaged hair cells. To understand better the reasons underpinning such disparities in regeneration among vertebrates, we set out to define at high resolution the changes in gene expression associated with the regeneration of hair cells in the zebrafish lateral line. We performed RNA-Seq analyses on regenerating support cells purified by FACS. The resulting expression data were subjected to pathway enrichment analyses, and the differentially expressed genes were validated in vivo via whole-mount in situ hybridizations. We discovered that cell cycle regulators are expressed hours before the activation of Wnt/β-catenin signaling following hair cell death. We propose that Wnt/β-catenin signaling is not involved in regulating the onset of proliferation but governs proliferation at later stages of regeneration. In addition, and in marked contrast to mammals, our data clearly indicate that the Notch pathway is significantly down-regulated shortly after injury, thus uncovering a key difference between the zebrafish and mammalian responses to hair cell injury. Taken together, our findings lay the foundation for identifying differences in signaling pathway regulation that could be exploited as potential therapeutic targets to promote either sensory epithelium or hair cell regeneration in mammals.
Stowers Institute for Medical Research, Kansas City, MO 64110.
Linjia
L
Jiang
Andres
A
Romero-Carvajal
Jeff S
JS
Haug
Christopher W
CW
Seidel
Tatjana
T
Piotrowski
D000818:Animals; D030801:Animals, Genetically Modified; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D018816:Genes, cdc; D006198:Hair Cells, Auditory / Q000166:cytology* / Q000502:physiology; D009355:Neomycin / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D051880:Receptors, Notch / Q000378:metabolism; D012038:Regeneration; D015398:Signal Transduction; D051153:Wnt Proteins / Q000378:metabolism; D015027:Zebrafish / Q000235:genetics*; D051176:beta Catenin / Q000378:metabolism
D051880:Receptors, Notch; D051153:Wnt Proteins; D051176:beta Catenin; D009355:Neomycin
Jak/Stat3; RNA sequencing; cdkn1b; neuromast; signaling pathway analysis