Shining light on the transcriptome: Molecular regulatory networks leading to a fast-growth phenotype by continuous light in an environmentally sensitive teleost (Atherinopsidae)

ElsevierVolume 235, October 2022, 112550Journal of Photochemistry and Photobiology B: BiologyHighlights•

Fish raised in continuous illumination presented a fast-growth phenotype.

Global downregulation of genes was observed in continuous illumination.

Continuous light since fertilization upregulated ROS response genes.

Epigenetic marks are modulated in fish under continuous illumination.

Abstract

Photoperiod can profoundly affect the physiology of teleost fish, including accelerated growth here defined as “fast growth phenotypes”. However, molecular regulatory networks (MRNs) and biological processes being affected by continuous illumination and which allow some teleost species evident plasticity to thrive under this condition are not yet clear. Therefore, to provide a broad perspective of such mechanisms, Chirostoma estor fish were raised and sampled for growth under a simulated control (LD) 12 h Light: 12 h Dark or a continuous illumination (LL) 24 h Light: 0 h Dark since fertilization. The experiment lasted 12 weeks after hatching (wah), the time at which fish were sampled for growth, length, and whole-body cortisol levels. Additionally, 3 heads of fish from each treatment were used to perform a de novo transcriptome analysis using Next-Generation Sequencing. Fish in LL developed the fast growth phenotype with significant differences visible at 4 wah and gained 66% more mass by 12 wah than LD fish. Cortisol levels under LL were below basal levels at all times compared to fish in LD, suggesting circadian dysregulation effects. A strong effect of LL was observed in samples with a generalized down-regulation of genes except for Reactive Oxygen Species responses, genome stability, and growth biological processes. To our knowledge, this work is the first study using a transcriptomic approach to understand environmentally sensitive MRNs that mediate phenotypic plasticity in fish submitted to continuous illumination. This study gives new insights into the plasticity mechanisms of teleost fish under constant illumination.

Keywords

Continuous illumination

Growth

Fish

Reactive oxygen species

Fertilization

Gene expression

View full text

© 2022 Elsevier B.V. All rights reserved.

留言 (0)

沒有登入
gif