Congratulations to the Loesgen Lab, in collaboration with the Martindale Lab for their paper "Cnidarian–algal partnerships structure bacterial communities during strobilation in Cassiopea xamachana" in the journal ISME Communications.
The project was led by former Loesgen Lab Postdoc Dr. Federica Montesanto and supported by Dr. Mark McCauley, in collaboration with the Martindale Lab (Cody Miner, Bailey Steinworth, Dr. Mark Martindale). Other collaborators are the labs of Dr. Virginia Weis (Oregon State U), Dr. Yehia Mechref (Texas Tech), Dr. Tingting Xiang (UC Riverside), Dr. Aki Ohdera (Stony Book U), and Dr. Moncia Medina (UCLA).
In this project, they studied the effects of the microbiome on the life-cycle of the Floridian local, upside-down jellyfish Cassiopea xamachana. For Cassiopea, the polyp-to-medusa transition (strobilation) requires the establishment of symbiosis with Symbiodiniaceae algal partners, yet bacterial community dynamics during this developmental process remain unknown. They experimentally induced symbiosis in aposymbiotic polyps using four algal treatments: xenic Symbiodinium microadriaticum (native symbiont), xenic Breviolum minutum, antibiotic-treated B. minutum, and a photosynthetically impaired B. minutum mutant. They combined 16S rRNA gene sequencing with measurements of photosynthetic efficiency, asexual budding, and algal surface N-glycan profiles to characterize holobiont assembly during symbiosis onset and strobilation.
Their work identifies bacterial signatures that consistently distinguish strobilating polyps from non-strobilating aposymbiotic and mutant polyps, in addition to potential bacterial biomarkers associated with successful metamorphosis. Together, these results reveal coordinated changes in algal physiology, surface glycan profiles and bacterial community structure associated with successful strobilation in C. xamachana, and support a model in which tripartite host–alga–bacteria interactions influence cnidarian life stage transitions.