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  • Characterization of a sperm motility signalling pathway in a gonochoric coral suggests conservation across cnidarian sexual systems
Title: Characterization of a sperm motility signalling pathway in a gonochoric coral suggests conservation across cnidarian sexual systems
Most stony corals liberate their gametes into the water column via broadcast spawning, where fertilization hinges upon the activation of directional sperm motility. Sperm from gonochoric and hermaphroditic corals display distinct morphological and molecular phenotypes, yet it is unknown whether the signalling pathways controlling sperm motility are also distinct between these sexual systems. Here, we addressed this knowledge gap using the gonochoric, broadcast spawning coralAstrangia poculata. We found that cytosolic alkalinization of sperm activates the pH-sensing enzyme soluble adenylyl cyclase (sAC), which is required for motility. Additionally, we demonstrate for the first time in any cnidarian that sAC activity leads to protein kinase A (PKA) activation, and that PKA activity contributes to sperm motility activation. Ultrastructures ofA. poculatasperm displayed morphological homology with other gonochoric cnidarians, and sAC exhibited broad structural and functional conservation across this phylum. These results indicate a conserved role for pH-dependent sAC-cAMP-PKA signalling in sperm motility across coral sexual systems, and suggest that the role of this pathway in sperm motility may be ancestral in metazoans. Finally, the dynamics of this pH-sensitive pathway may play a critical role in determining the sensitivity of marine invertebrate reproduction to anthropogenic ocean acidification.  more » « less
Award ID(s):
1923743
PAR ID:
10467266
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
The Royal Society Publishing
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
290
Issue:
2004
ISSN:
0962-8452
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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