Coral reefs have been challenged by the current rate and severity of
environmental change that might outpace their ability to adapt and
survive. Current research focuses on understanding how microbial
communities and epigenetic changes separately affect phenotypes and gene
expression of corals. Here, we provide the hypothesis that
coral-associated microorganisms may directly or indirectly affect the
coral's phenotypic response through the modulation of its epigenome.
Homologs of ankyrin-repeat protein A and internalin B, which indirectly
cause histone modifications in humans, as well as Rv1988 histone
methyltransferase, and the DNA methyltransferases Rv2966c, Mhy1, Mhy2,
and Mhy3 found in coral-associated bacteria indicate that there are
potential host epigenome-modifying proteins in the coral microbiome.
With the ideas presented here, we suggest that microbiome manipulation
may be a means to alter a coral's epigenome, which could aid the current
efforts to protect coral reefs.