Characterization of deep-sea benthic invertebrate megafauna of the Galapagos Islands

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Salinas-de-León, P., Martí-Puig, P., Buglass, S., Arnés-Urgellés, C., Rastoin-Laplane, E., Creemers, M., Cairns, S., Fisher, C., O'Hara, T., Ott, B., Raineault, N. A., Reiswig, H., Rouse, G., Rowley, S., Shank, T. M., Suarez, J., Watling, L., Wicksten, M. K., & Marsh, L. Characterization of deep-sea benthic invertebrate megafauna of the Galapagos Islands. Scientific Reports, 10(1), (2020): 13894, doi:10.1038/s41598-020-70744-1.The deep sea represents the largest and least explored biome on the planet. Despite the iconic status of the Galapagos Islands and being considered one of the most pristine locations on earth, the deep-sea benthic ecosystems of the archipelago are virtually unexplored in comparison to their shallow-water counterparts. In 2015, we embarked on a multi-disciplinary scientific expedition to conduct the first systematic characterization of deep-sea benthic invertebrate communities of the Galapagos, across a range of habitats. We explored seven sites to depths of over 3,300 m using a two-part Remotely Operated Vehicle (ROV) system aboard the E/V Nautilus, and collected 90 biological specimens that were preserved and sent to experts around the world for analysis. Of those, 30 taxa were determined to be undescribed and new to science, including members of five new genera (2 sponges and 3 cnidarians). We also systematically analysed image frame grabs from over 85 h of ROV footage to investigate patterns of species diversity and document the presence of a range of underwater communities between depths of 290 and 3,373 m, including cold-water coral communities, extensive glass sponge and octocoral gardens, and soft-sediment faunal communities. This characterization of Galapagos deep-sea benthic invertebrate megafauna across a range of ecosystems represents a first step to study future changes that may result from anthropogenic impacts to the planet’s climate and oceans, and informed the creation of fully protected deep-water areas in the Galapagos Marine Reserve that may help preserve these unique communities in our changing planet.We are thankful to the Ocean Exploration Trust as well as the pilots and crew aboard the E/V Nautilus during cruise NA064 for their assistance in sample collection and exploration using the Hercules ROV. Thank you to the NOAA Office of Exploration and Research for funding the E/V Nautilus Exploration Program (NA15OAR0110220). Further acknowledgements and thanks go out to the Charles Darwin Foundation and the Galapagos National Park Directorate for their collaboration and assistance in the exploration of the Galapagos Platform conducted under research permits PC-26–15 & PC-45-15. We also gratefully recognize the Government of Ecuador via the Ecuadorian Navy for permission to operate in their territorial waters. This research was supported by a grant from the Helmsley Charitable Trust and the Gordon and Betty Moore Foundation. This publication is contribution number 2354 of the Charles Darwin Foundation for the Galapagos Islands

Publisher Correction: Biodiversity, environmental drivers, and sustainability of the global deep-sea sponge microbiome

The original version of the Description of Additional Supplementary Files associated with this Article contained errors in the legends of Supplementary Data 5–8 and omitted legends for the Source Data. The HTML has been updated to include a corrected version of the Description of Additional Supplementary Files; the original incorrect version of this file can be found as Supplementary Information associated with this Correction

Biodiversity, environmental drivers, and sustainability of the global deep-sea sponge microbiome

In the deep ocean symbioses between microbes and invertebrates are emerging as key drivers of ecosystem health and services. We present a large-scale analysis of microbial diversity in deep-sea sponges (Porifera) from scales of sponge individuals to ocean basins, covering 52 locations, 1077 host individuals translating into 169 sponge species (including understudied glass sponges), and 469 reference samples, collected anew during 21 ship-based expeditions. We demonstrate the impacts of the sponge microbial abundance status, geographic distance, sponge phylogeny, and the physical-biogeochemical environment as drivers of microbiome composition, in descending order of relevance. Our study further discloses that fundamental concepts of sponge microbiology apply robustly to sponges from the deep-sea across distances of >10,000 km. Deep-sea sponge microbiomes are less complex, yet more heterogeneous, than their shallow-water counterparts. Our analysis underscores the uniqueness of each deep-sea sponge ground based on which we provide critical knowledge for conservation of these vulnerable ecosystems

Zebrafish ProVEGF-C Expression, Proteolytic Processing and Inhibitory Effect of Unprocessed ProVEGF-C during Fin Regeneration

BACKGROUND: In zebrafish, vascular endothelial growth factor-C precursor (proVEGF-C) processing occurs within the dibasic motif HSIIRR(214) suggesting the involvement of one or more basic amino acid-specific proprotein convertases (PCs) in this process. In the present study, we examined zebrafish proVEGF-C expression and processing and the effect of unprocessed proVEGF-C on caudal fin regeneration. METHODOLOGY/PRINCIPAL FINDINGS: Cell transfection assays revealed that the cleavage of proVEGF-C, mainly mediated by the proprotein convertases Furin and PC5 and to a less degree by PACE4 and PC7, is abolished by PCs inhibitors or by mutation of its cleavage site (HSIIRR(214) into HSIISS(214)). In vitro, unprocessed proVEGF-C failed to activate its signaling proteins Akt and ERK and to induce cell proliferation. In vivo, following caudal fin amputation, the induction of VEGF-C, Furin and PC5 expression occurs as early as 2 days post-amputation (dpa) with a maximum levels at 4-7 dpa. Using immunofluorescence staining we localized high expression of VEGF-C and the convertases Furin and PC5 surrounding the apical growth zone of the regenerating fin. While expression of wild-type proVEGF-C in this area had no effect, unprocessed proVEGF-C inhibited fin regeneration. CONCLUSIONS/SIGNIFICANCES: Taken together, these data indicate that zebrafish fin regeneration is associated with up-regulation of VEGF-C and the convertases Furin and PC5 and highlight the inhibitory effect of unprocessed proVEGF-C on fin regeneration

Open surgery for abdominal aortic aneurysm or aorto-iliac occlusive disease--clinical and ultrasonographic long-term results.

OBJECTIVE: To determine postoperative and long-term outcome and assess the relevance of abdominal ultrasound (US) after surgery for abdominal aortic aneurysm (AAA) or aortoiliac occlusive disease (AIOD). METHODS: Records of 1704 consecutive patients having graft implantation from 1988 to 2000, either for AAA (n = 1144) or for AIOD (n = 560), were reviewed. In 2006, follow-up was 9180 patients-years for the AAA group and 5450 patients-years for the AIOD group. Among 1006 alive patients, 377 were invited randomly for US and clinical examination. RESULTS: Hospital death occurred in 99 patients (8.6%) of the AAA group (53% in ruptured and 2% in elective AAA), and in 18 patients of the AIOD group (3.2%). There were 581 late deaths, including eight due to prosthesis infection, one to pseudo-aneurysm rupture, and one to graft thrombosis (0.6% graft-related mortality). Prosthesis thrombosis occurred in 32 patients (26 in AIOD group, p < 0.001), and graft infection in 26 (17 in AAA group, p < 0.01). Pseudoaneurysms developed in 90 patients (68 in AIOD group, p < 0.001), including eight at the proximal aortic, one at the distal aortic, two at the iliac and 79 at the femoral anastomosis. In the AAA group only, surgery was required for a new thoraco-abdominal and pararenal aneurysm in eight and four patients, respectively, while US evidenced a 26-35 and a 36-50 mm supraanastomotic aortic dilatation in 65 (32%) and in 14 (7%) patients, at a mean follow-up of 10.5 and 9.3 years, respectively. CONCLUSION: Long-term results are good after open surgery for AAA or AIOD. Prosthesis infection and anastomotic pseudo-aneurysm are the main causes of graft-related mortality and morbidity, respectively. Because of high incidence of asymptomatic supraanastomotic aortic dilatation, all patients with a history of AAA repair should have regular abdominal US

Effet de l’eutrophisation sur la macrofaune benthique des lagunes méditerranéennes

Les lagunes méditerranéennes sont aujourd’hui décrites comme des écosystèmes littoraux complexes dont les caractéristiques environnementales sont variables dans l’espace (mosaïque d’habitats) et dans le temps. Les fluctuations temporelles des conditions abiotiques s’exprimant aux échelles intra- et inter-annuelle représente en elle-même une première source de stress naturel pour les communautés biologiques associées et en particulier de la macrofaune benthique du fait de leur faible capacité de mobilité. Depuis les années 1960, ces lagunes par définition confinées sont également soumises à de nombreuses pressions anthropiques dont l’accroissement des apports en azote et en phosphore est reconnu aujourd'hui comme étant l’une des causes majeures de la dégradation des écosystèmes côtiers. Basé sur l’utilisation de données historiques collectées depuis 1999 ainsi que sur de nouvelles campagnes d’échantillonnage, ce projet vise à comprendre comment la macrofaune benthique se structure spatialement et temporellement au sein des lagunes méditerranéennes. À travers l’utilisation d’approches taxonomiques et fonctionnelles à plusieurs échelles de temps et d’espace, les résultats de ce projet mettent en évidence la complexité du lien entre l’environnement et la distribution de la macrofaune benthique au sein des lagunes méditerranéennes. Malgré la constitution de jeu de données complémentaires, il est apparu difficile de dissocier les effets de l’eutrophisation des fluctuations naturelles sur la macrofaune benthique au sein des lagunes. À l’échelle de la façade méditerranéenne, la structuration spatiale de la macrofaune serait déterminée principalement par l'hydromorphologie des lagunes et la diversité de l'habitat benthique à l'échelle de la lagune. L'eutrophisation et les facteurs de stress associés agiraient sur les communautés existantes en réduisant la richesse et la diversité taxonomique. L’étude de la dynamique temporelle des lagunes méditerranéennes vis-à-vis de l’eutrophisation n’a en revanche pas permis d’illustrer un lien clair entre l’évolution des conditions evironnementales et la strucure des communautés benthiques en lagune. L’acquisition de données à l’échelle intra-lagunaire et intra-annuelle dans le cadre de ce projet a permis d’illustrer la variabilité de la structure des communautés benthiques au sein même des lagunes méditerranéennes. La structuration de l’habitat et en particulier de la couverture en macrophyte est ici décrite comme un facteur clé expliquant la distribution de la macrofaune benthique aussi bien dans le temps et dans l’espace. L’absence de prise en compte de cette variabilité dans les stratégies d’acquisition de données dans le cadre de la DCE explique vraissemblablement une partie des difficultés rencontrées dans l’interprétation des données dans le cadre réglementaire. Dans un contexte de conservation de la biodiversité et des fonctionnalités écologiques des milieux lagunaires, il apparaît donc indispensable de considérer une description fine des habitats et de leurs fonctions associées

Furin Is the Primary in Vivo Convertase of Angiopoietin-like 3 and Endothelial Lipase in Hepatocytes

The proprotein convertases (PCs) furin, PC5/6, and PACE4 exhibit unique and/or complementary functions. Their knockout (KO) in mice resulted in strong and specific phenotypes demonstrating that, in vivo, these PCs are unique and essential during development. However, they also exhibit redundant functions. Liver angiopoietin-like 3 (ANGPTL3) inhibits lipolysis by binding to lipoprotein lipases. It is found in the plasma as full length and truncated forms. The latter is more active and generated by cleavage at a furin-like site. Endothelial lipase (EL) binds heparin sulfate proteoglycans on cell surfaces and catalyzes the hydrolysis of HDL phospholipids. EL activity is regulated by two endogenous inhibitors, ANGPTL3 and ANGPTL4, and by PCs that inactivate EL through cleavage releasing the N-terminal catalytic and C-terminal lipid-binding domains. Herein, because furin and PC5/6 complete KOs are lethal, we used mice lacking furin or PC5/6 specifically in hepatocytes (hKO) or mice completely lacking PACE4. In primary hepatocytes, ANGPTL3 was processed into a shorter form of ANGPTL3 intracellularly by furin only, and extracellularly mainly by PACE4. In vivo, the absence of furin in hepatocytes reduced by similar to 50% the circulating levels of cleaved ANGPTL3, while the lack of PACE4 had only a minor effect. Analysis of the EL processing in primary hepatocytes and in vivo revealed that it is mostly cleaved by furin. However, the lack of furin or PC5/6 in hepatocytes and complete PACE4 KO did not appreciably modify plasma HDL levels or EL activity. Thus, inhibition of furin in liver would not be expected to modify the plasma lipid profiles