ALBERT

Beschreibung: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kuehn, E., Clausen, D. S., Null, R. W., Metzger, B. M., Willis, A. D., & Ozpolat, B. D. Segment number threshold determines juvenile onset of germline cluster expansion in Platynereis dumerilii. Journal of Experimental Zoology Part B: Molecular and Developmental Evolution, (2021.): 1-16, https://doi.org/10.1002/jez.b.23100.

Beschreibung: Development of sexual characters and generation of gametes are tightly coupled with growth. Platynereis dumerilii is a marine annelid that has been used to study germline development and gametogenesis. P. dumerilii has germ cell clusters found across the body in the juvenile worms, and the clusters eventually form the gametes. Like other segmented worms, P. dumerilii grows by adding new segments at its posterior end. The number of segments reflect the growth state of the worms and therefore is a useful and measurable growth state metric to study the growth-reproduction crosstalk. To understand how growth correlates with progression of gametogenesis, we investigated germline development across several developmental stages. We discovered a distinct transition period when worms increase the number of germline clusters at a particular segment number threshold. Additionally, we found that keeping worms short in segment number, by manipulating environmental conditions or via amputations, supported a segment number threshold requirement for germline development. Finally, we asked if these clusters in P. dumerilii play a role in regeneration (as similar free-roaming cells are observed in Hydra and planarian regeneration) and found that the clusters were not required for regeneration in P. dumerilii, suggesting a strictly germline nature. Overall, these molecular analyses suggest a previously unidentified developmental transition dependent on the growth state of juvenile P. dumerilii leading to substantially increased germline expansion.

Beschreibung: Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health under Award Number R35GM138008 (to BDÖ) and R35GM133420 (to ADW) and Hibbitt Startup Funds (to BDÖ).

Beschreibung: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Jin, D., Hoagland, P., & Ashton, A. D. Risk averse choices of managed beach widths under environmental uncertainty. Natural Resource Modeling, (2021): e12324, https://doi.org/10.1111/nrm.12324.

Beschreibung: Applying a theoretical geo-economic approach, we examined key factors affecting decisions about the choice of beach width when eroded coastal beaches are being nourished (i.e., when fill is placed to widen a beach). Within this geo-economic framework, optimal beach width is positively related to its values for hazard protection and recreation and negatively related to nourishment costs and the discount rate. Using a dynamic modeling framework, we investigated the time paths of beach width and nourishment that maximized net present value under an accelerating sea level. We then analyzed how environmental uncertainty about expected future beach width, arising from natural shoreline dynamics, intermittent large storms, or sea-level rise, leads to economic choices favoring narrower beaches. Risk aversion can affect a coastal property owner's choice of beach width in contradictory ways: the expected benefits of hazard protection must be balanced against the expected costs of repeated nourishment actions.

Beschreibung: Support for this study was provided by NSF Grant No. ARG 1518503, WHOI Sea Grant (NOAA Award Number: NA18OAR4170104), and the J. Seward Johnson Fund in Support of the Marine Policy Center.

Beschreibung: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Özpolat, B. D., Randel, N., Williams, E. A., Bezares-Calderón, L. A., Andreatta, G., Balavoine, G., Bertucci, P. Y., Ferrier, D. E. K., Gambi, M. C., Gazave, E., Handberg-Thorsager, M., Hardege, J., Hird, C., Hsieh, Y.-W., Hui, J., Mutemi, K. N., Schneider, S. Q., Simakov, O., Vergara, H. M., Jékely, G., Tessmar-Raible, K., Raible, F., Arendt, D. The Nereid on the rise: Platynereis as a model system. EvoDevo, 12(1), (2021): 10, https://doi.org/10.1186/s13227-021-00180-3.

Beschreibung: The Nereid Platynereis dumerilii (Audouin and Milne Edwards (Annales des Sciences Naturelles 1:195–269, 1833) is a marine annelid that belongs to the Nereididae, a family of errant polychaete worms. The Nereid shows a pelago-benthic life cycle: as a general characteristic for the superphylum of Lophotrochozoa/Spiralia, it has spirally cleaving embryos developing into swimming trochophore larvae. The larvae then metamorphose into benthic worms living in self-spun tubes on macroalgae. Platynereis is used as a model for genetics, regeneration, reproduction biology, development, evolution, chronobiology, neurobiology, ecology, ecotoxicology, and most recently also for connectomics and single-cell genomics. Research on the Nereid started with studies on eye development and spiralian embryogenesis in the nineteenth and early twentieth centuries. Transitioning into the molecular era, Platynereis research focused on posterior growth and regeneration, neuroendocrinology, circadian and lunar cycles, fertilization, and oocyte maturation. Other work covered segmentation, photoreceptors and other sensory cells, nephridia, and population dynamics. Most recently, the unique advantages of the Nereid young worm for whole-body volume electron microscopy and single-cell sequencing became apparent, enabling the tracing of all neurons in its rope-ladder-like central nervous system, and the construction of multimodal cellular atlases. Here, we provide an overview of current topics and methodologies for P. dumerilii, with the aim of stimulating further interest into our unique model and expanding the active and vibrant Platynereis community.

Beschreibung: Funding resources are shown after author initials. EAW: BBSRC David Phillips Fellowship BB/T00990X/1. BDÖ: NIH NIGMS MIRA 1R35GM138008-01; NSF-EDGE Award no 1923429; Hibbitt Startup Funds. GJ, LABC, CH: Wellcome Trust Investigator Award 214337/Z/18/Z. KNM: Marie Sklodowska-Curie fellow supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 766053, project EvoCELL. NR: European Union Horizon 2020, Marie Skłodowska-Curie Grant No 838225. MCG: Stazione Zoologica A. Dohrn (Napoli) and the Ischia Marine Center technical staff; Open University PhD programme; ASSEMBLE; PON-MODO project (Campania Region, Italy), RITMARE - Flag project, Italy; MARES Consortium. Thanks to the ECCSEL - NatLab Italy facilities, managed by the OGS (Trieste), to support collection at Panarea and Vulcano islands. JDH: NERC award NE/T001577/1. MHT: Deutsche Forschungsgemeinschaft (DFG), Grant Number TO563/7-1. EG and MV: Labex ‘Who Am I?’ (No. ANR-11-LABX-0071) funded by the French Government through its ‘Investments for the Future’ program operated by the ANR under Grant No. ANR-11-IDEX-0005-01, Centre National de la Recherche Scientifique (DBM Grant), Université de Paris (IDEX Emergence grant 2020), Agence Nationale de la Recherche (Grant TELOBLAST no. ANR-16-CE91-0007; Grant STEM No. ANR-19-CE27-0027-02), the «Association pour la Recherche sur le Cancer» (Grant PJA 20191209482), and the «Ligue Nationale Contre le Cancer» (Grant RS20/75-20). SQS: NSF (US) Award IOS-1455185, MOST (TW) 108-2311-B-001-002-MY3, Academia Sinica Career Development Award AS-CDA-110-L02, and the Institute of Cellular and Organismic Biology (ICOB) of Academia Sinica (TW). YWH: Deutsche Forschungsgemeinschaft (DFG), grant number TO563/7-1 (to Pavel Tomancak). OS: Austrian Science Fund Grant P32190. GB: The Balavoine Lab was funded by the CNRS, the Université de Paris and grants from the ANR (TELOBLAST no. ANR-16-CE91-0007) and from the ARC (PJA 20181208248). FR and KTR: The research leading to these results has received funding from the European Research Council under the European Community’s Seventh Framework Programme (FP7/2007–2013)/ERC Grant Agreement 260304 (F.R.) and ERC Grant Agreement 337011 (K.T.-R.); the Horizon 2020 Programme ERC Grant Agreement 81995 (K.T.-R.); the research platforms ‘Rhythms of Life’ (K.T.-R., F.R.) and “Single-cell genomics of stem cells” (F.R.) of the University of Vienna; the Austrian Science Fund (FWF) START award, project Y413 (K.T.-R.); the Austrian Science Fund (FWF) projects P28970 (K.T.-R.) and I2972 (F.R.); the Austrian Science Fund (FWF) grant F78 (K.T.-R., F.R.). DA and PB ERC Advanced grant NeuralCellTypeEvo #788921.