Coral Reef Viruses in Kane'ohe Bay, Hawai'i: Abundance, Diversity & Environmental Drivers

10.26686/wgtn.17008594.v1 ◽

2021 ◽

Author(s):

◽

William N S Arlidge

Keyword(s):

Coral Reef ◽

Water Column ◽

Marine Reserve ◽

Morphological Diversity ◽

Coral Tissue ◽

Epifluorescence Microscopy ◽

Environmental Drivers ◽

Viral Abundance ◽

Viral Community ◽

And Function

Viruses are a ubiquitous component of coral reef ecosystems, with several viral types, from at least seven prokaryotic and 20 eukaryotic virus families currently characterised from the surface mucopolysaccharide layer (SML), coral tissue and the water column. However, little is known about the ecology and function of these viruses. For example, what are the environmental drivers of viral abundance and diversity on coral reefs? In this study, the abundance and distribution of virus-like particles (VLPs) associated with the SML and reef water of the coral Montipora capitata were determined using epifluorescence microscopy, while transmission electron microscopy was employed to determine the morphological diversity of VLPs. Sampling was conducted across the Coconut Island Marine Reserve (CIMR) reef system, Kane’ohe Bay, O’ahu, Hawai’i. Viral abundance was correlated with select environmental drivers and prokaryote abundance, while non-metric multidimensional scaling was used to determine the key environmental drivers of the viral community assemblage. The water column contained high concentrations of VLPs (5.98 × 107 ml-1) and prokaryotes (3.11 × 106 ml-1), consistent with the considerable anthropogenic impacts at this location. In comparison, the SML contained lower concentrations of VLPs (2.61 × 107 ml-1) and prokaryotes (2.08 × 106 ml-1); of note, the densities of viruses and prokaryotes in the SML were strongly coupled while those in the reef water were not. VLP density in the water column varied spatially across the reef, with the most sheltered site and the only one not situated on the reef crest having a greater VLP density than the other sites. Temporal variations in the density of microbes (i.e. viruses and prokaryotes) in the reef water were pronounced, while in the SML microbial densities remained constant. However, no specific environmental drivers of this variability could be identified. In contrast, temperature and water quality were correlated with shifts in the morphological diversity of VLPs across the reef. Small (< 50 nm) polyhedral/spherical VLPs were dominant, and were positively correlated to chlorophyll-a concentration when in the SML. In this same habitat, Fuselloviridae-like VLPs, filamentous VLPs and bead-shaped VLPs were positively correlated to temperature. In the reef water a different pattern was apparent: large (> 100 nm) Podoviridae-like VLPs and elongate Myoviridae-like VLPs, as well as lemon-shaped VLPs of both size classes showed positive associations with turbidity, while large filamentous VLPs, Geminiviridae-like VLPs and rod-shaped VLPs were positively associated with temperature. These results demonstrate that the viral community of Coconut Island’s reef is highly diverse, and subject to spatial and temporal change, especially in the water column. However, while the environmental drivers of viral diversity were partly elucidated, we are still a long way from understanding the drivers of viral abundance. More detailed study, both spatially and temporally, of the CIMR environment is required, as is comprehensive molecular analysis of the viral community of Kane’ohe Bay. Only then can we begin to understand the importance of viruses to the health and function of this, and other reef sites.

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Coral Reef Viruses in Kane'ohe Bay, Hawai'i: Abundance, Diversity & Environmental Drivers

10.26686/wgtn.17011811.v1 ◽

2021 ◽

Author(s):

◽

William N S Arlidge

Keyword(s):

Coral Reef ◽

Water Column ◽

Marine Reserve ◽

Morphological Diversity ◽

Coral Tissue ◽

Epifluorescence Microscopy ◽

Environmental Drivers ◽

Viral Abundance ◽

Viral Community ◽

And Function

Viruses are a ubiquitous component of coral reef ecosystems, with several viral types, from at least seven prokaryotic and 20 eukaryotic virus families currently characterised from the surface mucopolysaccharide layer (SML), coral tissue and the water column. However, little is known about the ecology and function of these viruses. For example, what are the environmental drivers of viral abundance and diversity on coral reefs? In this study, the abundance and distribution of virus-like particles (VLPs) associated with the SML and reef water of the coral Montipora capitata were determined using epifluorescence microscopy, while transmission electron microscopy was employed to determine the morphological diversity of VLPs. Sampling was conducted across the Coconut Island Marine Reserve (CIMR) reef system, Kane’ohe Bay, O’ahu, Hawai’i. Viral abundance was correlated with select environmental drivers and prokaryote abundance, while non-metric multidimensional scaling was used to determine the key environmental drivers of the viral community assemblage. The water column contained high concentrations of VLPs (5.98 × 107 ml-1) and prokaryotes (3.11 × 106 ml-1), consistent with the considerable anthropogenic impacts at this location. In comparison, the SML contained lower concentrations of VLPs (2.61 × 107 ml-1) and prokaryotes (2.08 × 106 ml-1); of note, the densities of viruses and prokaryotes in the SML were strongly coupled while those in the reef water were not. VLP density in the water column varied spatially across the reef, with the most sheltered site and the only one not situated on the reef crest having a greater VLP density than the other sites. Temporal variations in the density of microbes (i.e. viruses and prokaryotes) in the reef water were pronounced, while in the SML microbial densities remained constant. However, no specific environmental drivers of this variability could be identified. In contrast, temperature and water quality were correlated with shifts in the morphological diversity of VLPs across the reef. Small (< 50 nm) polyhedral/spherical VLPs were dominant, and were positively correlated to chlorophyll-a concentration when in the SML. In this same habitat, Fuselloviridae-like VLPs, filamentous VLPs and bead-shaped VLPs were positively correlated to temperature. In the reef water a different pattern was apparent: large (> 100 nm) Podoviridae-like VLPs and elongate Myoviridae-like VLPs, as well as lemon-shaped VLPs of both size classes showed positive associations with turbidity, while large filamentous VLPs, Geminiviridae-like VLPs and rod-shaped VLPs were positively associated with temperature. These results demonstrate that the viral community of Coconut Island’s reef is highly diverse, and subject to spatial and temporal change, especially in the water column. However, while the environmental drivers of viral diversity were partly elucidated, we are still a long way from understanding the drivers of viral abundance. More detailed study, both spatially and temporally, of the CIMR environment is required, as is comprehensive molecular analysis of the viral community of Kane’ohe Bay. Only then can we begin to understand the importance of viruses to the health and function of this, and other reef sites.

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Coral Reef Viruses in Kane'ohe Bay, Hawai'i: Abundance, Diversity & Environmental Drivers

10.26686/wgtn.17011811 ◽

2021 ◽

Author(s):

◽

William N S Arlidge

Keyword(s):

Coral Reef ◽

Water Column ◽

Marine Reserve ◽

Morphological Diversity ◽

Coral Tissue ◽

Epifluorescence Microscopy ◽

Environmental Drivers ◽

Viral Abundance ◽

Viral Community ◽

And Function

Viruses are a ubiquitous component of coral reef ecosystems, with several viral types, from at least seven prokaryotic and 20 eukaryotic virus families currently characterised from the surface mucopolysaccharide layer (SML), coral tissue and the water column. However, little is known about the ecology and function of these viruses. For example, what are the environmental drivers of viral abundance and diversity on coral reefs? In this study, the abundance and distribution of virus-like particles (VLPs) associated with the SML and reef water of the coral Montipora capitata were determined using epifluorescence microscopy, while transmission electron microscopy was employed to determine the morphological diversity of VLPs. Sampling was conducted across the Coconut Island Marine Reserve (CIMR) reef system, Kane’ohe Bay, O’ahu, Hawai’i. Viral abundance was correlated with select environmental drivers and prokaryote abundance, while non-metric multidimensional scaling was used to determine the key environmental drivers of the viral community assemblage. The water column contained high concentrations of VLPs (5.98 × 107 ml-1) and prokaryotes (3.11 × 106 ml-1), consistent with the considerable anthropogenic impacts at this location. In comparison, the SML contained lower concentrations of VLPs (2.61 × 107 ml-1) and prokaryotes (2.08 × 106 ml-1); of note, the densities of viruses and prokaryotes in the SML were strongly coupled while those in the reef water were not. VLP density in the water column varied spatially across the reef, with the most sheltered site and the only one not situated on the reef crest having a greater VLP density than the other sites. Temporal variations in the density of microbes (i.e. viruses and prokaryotes) in the reef water were pronounced, while in the SML microbial densities remained constant. However, no specific environmental drivers of this variability could be identified. In contrast, temperature and water quality were correlated with shifts in the morphological diversity of VLPs across the reef. Small (< 50 nm) polyhedral/spherical VLPs were dominant, and were positively correlated to chlorophyll-a concentration when in the SML. In this same habitat, Fuselloviridae-like VLPs, filamentous VLPs and bead-shaped VLPs were positively correlated to temperature. In the reef water a different pattern was apparent: large (> 100 nm) Podoviridae-like VLPs and elongate Myoviridae-like VLPs, as well as lemon-shaped VLPs of both size classes showed positive associations with turbidity, while large filamentous VLPs, Geminiviridae-like VLPs and rod-shaped VLPs were positively associated with temperature. These results demonstrate that the viral community of Coconut Island’s reef is highly diverse, and subject to spatial and temporal change, especially in the water column. However, while the environmental drivers of viral diversity were partly elucidated, we are still a long way from understanding the drivers of viral abundance. More detailed study, both spatially and temporally, of the CIMR environment is required, as is comprehensive molecular analysis of the viral community of Kane’ohe Bay. Only then can we begin to understand the importance of viruses to the health and function of this, and other reef sites.

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Faculty Opinions recommendation of Local replenishment of coral reef fish populations in a marine reserve.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1084861.537795 ◽

2007 ◽

Author(s):

Mark Hay

Keyword(s):

Coral Reef ◽

Reef Fish ◽

Coral Reef Fish ◽

Marine Reserve ◽

Fish Populations

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Analysis of mitochondrial morphology and function with novel fixable fluorescent stains.

Journal of Histochemistry & Cytochemistry ◽

10.1177/44.12.8985128 ◽

1996 ◽

Vol 44 (12) ◽

pp. 1363-1372 ◽

Cited By ~ 344

Author(s):

M Poot ◽

Y Z Zhang ◽

J A Krämer ◽

K S Wells ◽

L J Jones ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Epifluorescence Microscopy ◽

Mitochondrial Morphology ◽

Microtubule Network ◽

Multiple Features ◽

Permeabilized Cells ◽

Dye Staining ◽

And Function

Investigation of mitochondrial morphology and function has been hampered because photostable, mitochondrion-specific stains that are retained in fixed, permeabilized cells have not been available. We found that in live cell preparations, the CMXRos and H2-CMXRos dyes were more photostable than rhodamine 123. In addition, fluorescence and morphology of mitochondria stained with the CMXRos and CMXRos-H2 dyes were preserved even after formaldehyde fixation and acetone permeabilization. Using epifluorescence microscopy, we showed that CMXRos and H2-CMXRos dye fluorescence fully co-localized with antibodies to subunit I of cytochrome c oxidase, indicating that the dyes specifically stain mitochondria. Confocal microscopy of these mitochondria yielded colored banding patterns, suggesting that these dyes and the mitochondrial enzyme localize to different suborganellar regions. Therefore, these stains provide powerful tools for detailed analysis of mitochondrial fine structure. We also used poisons that decrease mitochondrial membrane potential and an inhibitor of respiration complex II to show by flow cytometry that the fluorescence intensity of CMXRos and H2-CMXRos dye staining responds to changes in mitochondrial membrane potential and function. Hence, CMXRos has the potential to monitor changes in mitochondrial function. In addition, CMXRos staining was used in conjunction with spectrally distinct fluorescent probes for the cell nucleus and the microtubule network to concomitantly evaluate multiple features of cell morphology.

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Viral abundance and genome size distribution in the sediment and water column of marine and freshwater ecosystems

FEMS Microbiology Ecology ◽

10.1111/j.1574-6941.2007.00298.x ◽

2007 ◽

Vol 60 (3) ◽

pp. 397-410 ◽

Cited By ~ 36

Author(s):

Manuela Filippini ◽

Mathias Middelboe

Keyword(s):

Water Column ◽

Size Distribution ◽

Genome Size ◽

Freshwater Ecosystems ◽

Viral Abundance

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Tidal variability of nutrients in a coastal coral reef system influenced by groundwater

Biogeosciences ◽

10.5194/bg-15-997-2018 ◽

2018 ◽

Vol 15 (4) ◽

pp. 997-1009 ◽

Cited By ~ 3

Author(s):

Guizhi Wang ◽

Shuling Wang ◽

Zhangyong Wang ◽

Wenping Jing ◽

Yi Xu ◽

...

Keyword(s):

Coral Reef ◽

Water Column ◽

Water Depth ◽

Neap Tide ◽

Groundwater Discharge ◽

Spring Tide ◽

Biological Processes ◽

Reef System ◽

Nitrite Nitrate ◽

Coral Reef System

Abstract. To investigate variation in nitrite, nitrate, phosphate, and silicate in a spring–neap tide in a coral reef system influenced by groundwater discharge, we carried out a time-series observation of these nutrients and 228Ra, a tracer of groundwater discharge, in the Luhuitou fringing reef at Sanya Bay in the South China Sea. The maximum 228Ra, 45.3 dpm 100 L−1, appeared at low tide and the minimum, 14.0 dpm 100 L−1, appeared during a flood tide in the spring tide. The activity of 228Ra was significantly correlated with water depth and salinity in the spring–neap tide, reflecting the tidal-pumping feature of groundwater discharge. Concentrations of all nutrients exhibited strong diurnal variation, with a maximum in the amplitude of the diel change for nitrite, nitrate, phosphate, and silicate in the spring tide of 0.46, 1.54, 0.12, and 2.68 µM, respectively. Nitrate and phosphate were negatively correlated with water depth during the spring tide but showed no correlation during the neap tide. Nitrite was positively correlated with water depth in the spring and neap tide due to mixing of nitrite-depleted groundwater and nitrite-rich offshore seawater. They were also significantly correlated with salinity (R2  ≥  0.9 and P < 0.05) at the ebb flow of the spring tide, negative for nitrate and phosphate and positive for nitrite, indicating the mixing of nitrite-depleted, nitrate- and phosphate-rich less saline groundwater and nitrite-rich, nitrate- and phosphate-depleted saline offshore seawater. We quantified variation in oxidized nitrogen (NOx) and phosphate contributed by biological processes based on deviations from mixing lines of these nutrients. During both the spring and neap tide biologically contributed NOx and phosphate were significantly correlated with regression slopes of 4.60 (R2  =  0.16) in the spring tide and 13.4 (R2  =  0.75) in the neap tide, similar to the composition of these nutrients in the water column, 5.43 (R2  =  0.27) and 14.2 (R2  =  0.76), respectively. This similarity indicates that the composition of nutrients in the water column of the reef system was closely related with biological processes during both tidal periods, but the biological influence appeared to be less dominant, as inferred from the less significant correlations (R2  =  0.16) during the spring tide when groundwater discharge was more prominent. Thus, the variability of nutrients in the coral reef system was regulated mainly by biological uptake and release in a spring–neap tide and impacted by mixing of tidally driven groundwater and offshore seawater during spring tide.

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The effect of the water column on submerged coral reef hyperspectral response

IEEE 1999 International Geoscience and Remote Sensing Symposium. IGARSS'99 (Cat. No.99CH36293) ◽

10.1109/igarss.1999.773586 ◽

2003 ◽

Author(s):

H. Holden ◽

E. LeDrew

Keyword(s):

Coral Reef ◽

Water Column

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hlh-12, a gene that is necessary and sufficient to promote migration of gonadal regulatory cells in C. elegans, evolved within the Caenorhabditis clade

Genetics ◽

10.1093/genetics/iyab127 ◽

2021 ◽

Author(s):

Hana E Littleford ◽

Karin Kiontke ◽

David H A Fitch ◽

Iva Greenwald

Keyword(s):

Ectopic Expression ◽

Morphological Diversity ◽

Nematode Species ◽

Bhlh Protein ◽

Vulval Development ◽

C Elegans ◽

Form And Function ◽

Somatic Gonad ◽

And Function ◽

Necessary And Sufficient

Abstract Specialized cells of the somatic gonad primordium of nematodes play important roles in the final form and function of the mature gonad. C. elegans hermaphrodites are somatic females that have a two-armed, U-shaped gonad that connects to the vulva at the midbody. The outgrowth of each gonad arm from the somatic gonad primordium is led by two female Distal Tip Cells (fDTC), while the Anchor Cell (AC) remains stationary and central to coordinate uterine and vulval development. The bHLH protein HLH-2 and its dimerization partners LIN-32 and HLH-12 had previously been shown to be required for fDTC specification. Here, we show that ectopic expression of both HLH-12 and LIN-32 in cells with AC potential transiently transforms them into fDTC-like cells. Furthermore, hlh-12 was known to be required for the fDTCs to sustain gonad arm outgrowth. Here, we show that ectopic expression of HLH-12 in the normally stationary AC causes displacement from its normal position, and that displacement likely results from activation of the leader program of fDTCs because it requires genes necessary for gonad arm outgrowth. Thus, HLH-12 is both necessary and sufficient to promote gonadal regulatory cell migration. As differences in female gonadal morphology of different nematode species reflect differences in the fate or migratory properties of the fDTCs or of the AC, we hypothesized that evolutionary changes in the expression of hlh-12 may underlie evolution of such morphological diversity. However, we were unable to identify an hlh-12 ortholog outside of Caenorhabditis. Instead, by performing a comprehensive phylogenetic analysis of all Class II bHLH proteins in multiple nematode species, we found that HLH-12 evolved within the Caenorhabditis clade, possibly by duplicative transposition of hlh-10. Our analysis suggests that control of gene regulatory hierarchies for gonadogenesis can be remarkably plastic during evolution without adverse phenotypic consequence.

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