CC BY
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10 • "PROTIST—2016
During this work we developed pipeline, based on publically available bioinformatics tools and our own scripts written in Python for transcriptome assembly and annotation. We have found 300 groups ofgenes, which not found outside Amoebozoa or were highly derived within this group of protists. Among them we selected 15 groups of genes with low level of paralogy and performed phylogenetic analysis and primers construction. These genes are promising DNA barcodes for studies of environmental diversity of Amoebozoa. Supported with MK-4853.2015.4 President grant, RFBR 16-34-60111 and SPSU grant 1.38.251.2014.
BURIED BUT NOT DEAD: INSIGHTS INTO THE DIVERSITY, PHYSIOLOGY, FUNCTIONS AND ECOLOGICAL ROLES OF DEEP SUBSEAFLOOR FUNGI USING AN INTEGRATED APPROACH
Burgaud G.1, Rédou V.1, Pachiadaki M.G23, Navarri M.1, Fleury Y.1, Barbier G.1, Edgcomb V.P.2
1 - Université de Brest, EA 3882, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, ESIAB, Technopôle de Brest Iroise, 29280Plouzané, France
2 - Woods Hole Oceanographic Institution, Department ofGeology and Geophysics, Woods Hole, Massachusetts, United States of America
3 - Bigelow Laboratories, East Boothbay, Maine, USA [email protected]
Bacteria and Archaea are the most commonly studied microorganisms in the marine environment, and habitats such as deep subseafloor ecosystems are no exception. However, recent studies strongly support the idea that deep subseafloor microbial communities include Fungi, which seem to dominate those micro-eukaryotic communities. Using sediment samples from the IODP Expedition 317 as a model, our aims were (i) to better understand the diversity, physiology and functions of deep subseafloor fungi and (ii) to provide clues about how they interact with other microbial populations in those communities. Using a record depth sediment core, fungal molecu-lar signatures and fungal cultures were obtained from samples as deep as 1740mbsf (Rédou et al. 2014) and 1884mbsf (Rédou et al. 2015), respectively. In spite of the fact that those complementary approaches revealed low diversity of higher fungal lineages, DNA and rRNA signatures as well as almost 200 cultured isolates provide direct evidence that fungi persist in this challenging habitat. Consistent with this idea, physiological analyses indicate some deep subseafloor fungal isolates appear well-adapted to in situ conditions.
Metatranscriptome analysis provided an examination of the functional repertoire of deep subseafloor fungi. Gene expression was assigned to metabolic and biosynthetic processes, responses to stress, cell and membrane functions, conidiogenesis and biosynthesis of secondary metabolites (Pachiadaki et al., in revision). These results all provide further support for the notion offungal presence and activity in the deep subseafloor biosphere, with the ability to interact with other microbial populations by synthesizing antimicrobial compounds (Navarri et al. 2016).
THE GREEN ALGA AND THE SALAMANDER:
A SUFFOCATING LOVE STORY
Burns J.A.1, Zhang H.2, Hill E.2, Kerney R.2, Kim E.1
1 - American Museum of Natural History
2 - Gettysburg College [email protected]
The recently discovered endosymbiosis between the green alga Oophila amblystomatis and the salamander Ambystoma maculatum is a unique relationship among the chloroplastida and vertebrates. Using a dual RNA-seq approach, we assembled novel transcriptomes ofthese two organisms and identified differentially expressed transcripts between ecto-and endo-symbiotic algae as well as between salamander cells with and without endosymbiotic algae. The results offer a glimpse at the changes in both organisms that take place during this novel endosymbiosis. We found that the intracellular algae downregulate nutrient transporters related to phosphate and nitrogen acquisition from the environment. They also exhibit hallmarks of cellular stress, especially related to osmotic stress, sulfur starvation, and hypoxia. Further, the results suggest that the alga undergoes a large scale metabolic shift from oxidative metabolism to fermentation with the potential evolution ofhydrogen gas. The salamander cells exhibit milder differences, including changes in gene expression indicating the initiation of an innate immune response to the alga, and alterations in nutrient sensing related to insulin sensitivity. The salamander cells do not exhibit large scale stress or apoptotic responses suggesting that intracellular algae are not a big drain on the salamander cell's resources.
GENOME AND TRANSCRIPTOME OF HEMI-STASIA PHAEOCYSTICOLA, A FLAGELLATE RELATED TO A NOVEL HYPER-DIVERSE CLADE OF MARINE PROTISTS Butenko A.1, Yabuki A.2, Flegontova O.34, Horak A.3, Flegontov P.135, Lukes J.346 1 - Life Science Research Centre, Faculty ofScience,
