In vivo tracking of histone H3 lysine 9 acetylation in Xenopus laevis during tail regeneration

Abstract

Xenopus laevis tadpoles can completely regenerate their appendages, such as tail and limbs, and therefore provide a unique model to decipher the molecular mechanisms of organ regeneration in vertebrates. Epigenetic modifications are likely to be involved in this remarkable regeneration capacity, but they remain largely unknown. To examine the involvement of histone modification during organ regeneration, we generated transgenic X. laevis ubiquitously expressing a fluorescent modification-specific intracellular antibody (Mintbody) that is able to track histone H3 lysine 9 acetylation (H3K9ac) in vivo through nuclear enhanced green fluorescent protein (EGFP) fluorescence. In embryos ubiquitously expressing H3K9ac-Mintbody, robust fluorescence was observed in the nuclei of somites. Interestingly, H3K9ac-Mintbody signals predominantly accumulated in nuclei of regenerating notochord at 24 h postamputation following activation of reactive oxygen species (ROS). Moreover, apocynin (APO), an inhibitor of ROS production, attenuated H3K9ac-Mintbody signals in regenerating notochord. Our results suggest that ROS production is involved in acetylation of H3K9 in regenerating notochord at the onset of tail regeneration. We also show this transgenic Xenopus to be a useful tool to investigate epigenetic modification, not only in organogenesis but also in organ regeneration.

Homeotic transformation of tails into limbs in anurans

“…It is expected that the establishment of positional information is mediated by epigenetic modification, for example, methylation and acetylation of histones and DNA methylation (Hayashi et al, 2015;Suzuki et al, 2016;Tseng & Levin, 2012;Yakushiji, Yokoyama, & Tamura, 2009). It is expected that the establishment of positional information is mediated by epigenetic modification, for example, methylation and acetylation of histones and DNA methylation (Hayashi et al, 2015;Suzuki et al, 2016;Tseng & Levin, 2012;Yakushiji, Yokoyama, & Tamura, 2009).…”

“…Recently, extensive epigenetic analyses of amphibian regeneration have been performed. It is expected that the establishment of positional information is mediated by epigenetic modification, for example, methylation and acetylation of histones and DNA methylation (Hayashi et al, 2015;Suzuki et al, 2016;Tseng & Levin, 2012;Yakushiji, Yokoyama, & Tamura, 2009). However, little is known about the roles of epigenetic regulation during tail regeneration.…”

“…However, little is known about the roles of epigenetic regulation during tail regeneration. Acetylation of histone H3 lysine 9 in the nuclei is accumulated in the regenerating notochord of the Xenopus tail 24 hr postamputation (Suzuki et al, 2016). It is unknown what gene expression is induced by the change in the acetylation pattern in the regenerating tail.…”

Magic wands of CRISPR—lots of choices for gene knock-in

“…Recently, Suzuki and colleagues reported a simple but important improvement in NHEJ-mediated knock-in strategy, referred to as the HITI (homology-independent targeted integration) method (Suzuki et al 2016a). They used a common single-guide RNA (sgRNA) for the cleavage of genomic target site and donor DNA, but the orientation of the sgRNA target site on the donor DNA was flipped.…”

Live imaging of H3K9 acetylation in plant cells

“…An increase in H3K9ac was detected as an increase in the ratio of nuclear to cytoplasmic intensity when a histone deacetylase inhibitor was added to hTERT-RPE1 cells expressing H3K9ac-mintbody11. Transgenic animals stably expressing H3K9ac-mintbody have been constructed in fruit fly ( Drosophila melanogaster ), zebrafish ( Danio rerio ) and Xenopus laevis 111213. An increase of H3K9ac could be monitored in specific regions during embryogenesis and organ development of these transgenic animals.…”