The endosymbiosis between most corals and their photosynthetic dinoflagellate partners begins early in the host life history, when corals are larvae or juvenile polyps. The capacity of coral larvae to buffer climate‐induced stress while in the process of symbiont acquisition could come with physiological trade‐offs that alter behaviour, development, settlement and survivorship. Here we examined the joint effects of thermal stress and symbiosis onset on colonization dynamics, survival, metamorphosis and host gene expression of
There are a wide range of developmental strategies in animal phyla, but most insights into adult body plan formation come from direct-developing species. For indirect-developing species, there are distinct larval and adult body plans that are linked together by metamorphosis. Some outstanding questions in the development of indirect-developing organisms include the extent to which larval tissue undergoes cell death during the process of metamorphosis and when and where the tissue that will give rise to the adult originates. How do the processes of cell division and cell death redesign the body plans of indirect developers? In this study, we present patterns of cell proliferation and cell death during larval body plan development, metamorphosis, and adult body plan formation, in the hemichordate
We identified distinct patterns of cell proliferation between larval and adult body plan formation of
Cell proliferation during the development of
- Award ID(s):
- 1656628
- NSF-PAR ID:
- 10367940
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- EvoDevo
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-9139
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Acropora digitifera larvae. We found that thermal stress decreased symbiont colonization of hosts by 50% and symbiont density by 98.5% over 2 weeks. Temperature and colonization also influenced larval survival and metamorphosis in an additive manner, where colonized larvae fared worse or prematurely metamorphosed more often than noncolonized larvae under thermal stress. Transcriptomic responses to colonization and thermal stress treatments were largely independent, while the interaction of these treatments revealed contrasting expression profiles of genes that function in the stress response, immunity, inflammation and cell cycle regulation. The combined treatment either cancelled or lowered the magnitude of expression of heat‐stress responsive genes in the presence of symbionts, revealing a physiological cost to acquiring symbionts at the larval stage with elevated temperatures. In addition, host immune suppression, a hallmark of symbiosis onset under ambient temperature, turned to immune activation under heat stress. Thus, by integrating the physical environment and biotic pressures that mediate presettlement event in corals, our results suggest that colonization may hinder larval survival and recruitment under projected climate scenarios. -
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Abstract The E93 transcription factor is a member of helix‐turn‐helix transcription factor family containing a Pip‐squeak motif. This ecdysone primary response gene was identified as a regulator of cell death in
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