Heat resilience in embryonic zebrafish revealed using an in vivo stress granule reporter

Abstract

Although the regulation of stress granules has become an intensely studied topic, current investigations of stress granule assembly, disassembly and dynamics are mainly performed in cultured cells. Here, we report the establishment of a stress granule reporter to facilitate the real-time study of stress granules in vivo. Using CRISPR/Cas9, we fused a green fluorescence protein (GFP) to endogenous G3BP1 in zebrafish. The GFP–G3BP1 reporter faithfully and robustly responded to heat stress in zebrafish embryos and larvae. The induction of stress granules varied by brain regions under the same stress condition, with the midbrain cells showing the highest efficiency and dynamics. Furthermore, pre-conditioning using lower heat stress significantly limited stress granule formation during subsequent higher heat stress. More interestingly, stress granule formation was much more robust in zebrafish embryos than in larvae and coincided with significantly elevated levels of phosphorylated eIF2α and enhanced heat resilience. Therefore, these findings have generated new insights into stress response in zebrafish during early development and demonstrated that the GFP–G3BP1 knock-in zebrafish could be a valuable tool for the investigation of stress granule biology.

Light-triggered switching of liposome surface charge directs delivery of membrane impermeable payloads in vivo

“…All UV irradiated embryos used in this study continued to develop normally without observable phenotypic abnormalities up to 6 dpf, confirming the suitability of this animal model for photoactivation studies 50 . Furthermore, any small potential increase in the temperature of the embryo as a result of UV irradiation will likely be counteracted by the remarkable resilience of the zebrafish embryo (from 1dpf) to heat stress 51 .…”

De novo variants in genes regulating stress granule assembly associate with neurodevelopmental disorders

“…SGs are membraneless compartments in eukaryotic cells that are dynamically induced upon varieties of stress conditions ( 12 ) and thought to be critical to maintain gene expression homeostasis during embryonic brain development ( 25 , 39 ). UBAP2L is an essential regulator for SG assembly ( 17 , 19 ).…”

“…The study of human organoids also revealed that oxygen deprivation on corticogenesis affects intermediate progenitor proliferation and underlies long-term neurodevelopmental impairment (38). SGs are membraneless compartments in eukaryotic cells that are dynamically induced upon varieties of stress conditions (12) and thought to be critical to maintain gene expression homeostasis during embryonic brain development (25,39). UBAP2L is an essential regulator for SG assembly (17,19).…”

Studying molecular interactions in the intact organism: fluorescence correlation spectroscopy in the living zebrafish embryo

“…Model organisms ranging from invertebrates, such as Caenorhabditis elegans (Beam et al 2012 ) and Drosophila melanogaster (Wang et al 2004 ), to vertebrates like Xenopus laevis and the zebrafish Danio rerio have all been studied with FCS (Shi et al 2009a , b ). The zebrafish, in particular, has greatly furthered the field of developmental biology with the use of FCS and other confocal-microscopy-related quantification technologies such as FCCS, Förster resonance energy transfer (FRET) and fluorescence recovery after photobleaching (FRAP) (Deng et al 2020 ; Wang et al 2019 ).…”