No trout about it: behavioural and transcriptional effects of long-term noise exposure in brook trout (Salvelinus fontinalis)

Canadian Journal of Fisheries and Aquatic Sciences, Journal Year: 2025, Volume and Issue: 82, P. 1 - 16

Published: Jan. 1, 2025

Exposure to acute noise sources can lead negative behavioural outcomes and fitness deficits in fishes, but it is unknown whether fish habituate chronic exposures. As underwater increases globally, understanding how long-term exposures affect behavioural, morphological, transcriptional measures of stress critical. We tested responses captive brook trout ( Salvelinus fontinalis) immediately after exposure a 2 weeks exposure. Behavioural tests quantified movements before, during, sound presentation, with morphological changes assessed through ears whole brains samples, respectively. Pre-control pre-experimental exhibited increased swimming distance velocity, the 2-week exposure, post-experimental showed no response while post-control group remained responsive. Post-experimental significant differences transcription levels genes involved neuroplastic, appetite, relative other groups. Together these results suggest that may appear unresponsive via metrics anthropogenic noises they still show at level possible effects.

Language: Английский

Long-range Atoh1 enhancers maintain competency for hair cell regeneration in the inner ear

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(51)

Published: Dec. 13, 2024

During tissue regeneration, lineage-related cells can switch their fate to replace missing cells. This cell plasticity is particularly prominent in more regenerative vertebrates such as zebrafish, yet the molecular basis by which transdifferentiate into another type upon injury remains unclear. Here, we investigate epigenetic of transdifferentiation inner ear, where supporting (SCs) generate mechanosensory hair (HCs) damage. By comparing chromatin landscapes zebrafish and green anole lizards versus nonregenerative mice, identified a class enhancers that function progenitors HCs then are selectively maintained SCs regenerate HCs. In particular, uncovered syntenic long-range for Atoh1 , master transcription factor HC differentiation. absence injury, these maintain accessibility through adulthood but prevented from driving atoh1a expression Notch repression. Deletion not only impaired formation during development also blocked ability regeneration. Moreover, defects were specific ear lateral line, revealing distinct mechanisms regeneration organs. These findings reveal enhancer maintains competency upregulate We propose continued developmental one may be common theme underlying adult vertebrates.

Language: Английский

Knockout of dhx38 Causes Inner Ear Developmental Defects in Zebrafish

Biomedicines, Journal Year: 2024, Volume and Issue: 13(1), P. 20 - 20

Published: Dec. 26, 2024

Background: Alternative splicing is essential for the physiological and pathological development of inner ear. Disruptions in this process can result both syndromic non-syndromic forms hearing loss. DHX38, a DEAH box RNA helicase, integral to pre-mRNA regulation plays critical roles development, cell differentiation, stem maintenance. However, its specific role ear remains undefined. Here, we utilized dhx38 knockout zebrafish model monitor morphology elucidate crucial DHX38 Methods: Bright-field morphological analysis situ hybridization were performed observe changes. Immunofluorescence semi-quantitative RT-PCR employed test apoptotic cells abnormal splicing. Results: The dhx38-/- mutant showed significant impairments, including decrescent otocysts, absent semicircular canal protrusion, smaller otoliths. These structural abnormalities accompanied by substantial DNA damage p53-dependent apoptosis within cells. that genes related repair morphogenesis are mutants. In summary, suggest promotes survival during ensuring correct repair.

Language: Английский