ד"ר מיגל פראדה

Biological oceanography; Phytoplankton ecology, cell biology and genetics; Regulation of life cycle strategies; Biotic interactions; Populations dynamics.

המחקר במעבדה שלי מתמקד באקולוגיה ובפיזיולוגיה של פיטופלנקטון ימי. באופן ספציפי, אני מעוניין להבין את מחזורי החיים של פיטופלנקטון ואת יחסי הגומלין בין פיטופלנקטון לוירוסים באוקיינוסים. עבודתי משלבת גם גישות אוקיאנוגרפיות לחקר אוכלוסיות טבעיות בים וגם גישות מעבדתיות לבדיקת התגובות של אורגניזמים פיטופלנקטונים באמצעות שיטות אופטיות ומולקולריות.

2016             ISF Equipment Grant - Integrated optical and biophysical platform to study the diversity, spatiotemporal dynamics, biotic interplay and physiology                                                               attributes of marine phytoplankton

2016-2020    ISF Research Grant - Life Cycle Strategies in Marine Phytoplankton: Spatiotemporal Dynamics, Biotic Interactions and Cellular Responses.

Lab overview

I am an experimental biologist generally interested in phytoplankton ecology and evolution as well as marine virology. Phytoplankton comprises a very diverse and heterogeneous assemblage of mainly single-celled microorganisms that form the basis of the marine food web and are major drivers of global biogeochemistry and Earth climate. I find particularly interesting the integrative cross-talk between ecology and cell biology, in order to characterize the dynamics of natural phytoplankton populations at sea, but also assess sub-cellular mechanisms underlying their role in the ecosystem. Over the last years, I’ve been particularly interested on the life cycle on marine phytoplankton, a process recurrently mediated by sexual reproduction (sexual cell fusion and meiosis) and resulting in the differentiation into alternate cell forms, which invariably entails major variations in the ecological dynamics and evolution of a given species. Yet, life cycles have been largely overlooked in phytoplankton research. Giving this premise, my lab focuses on the investigation of the main ecological and cellular differentiation between life cycle phases, assessing the role of each phase and the interplay with other organisms in the natural environment as well as on searching for triggers that regulate life phase transition. I believe that a better knowledge of phytoplankton life cycles will provide a holistic view on the functional significance of phytoplankton species and improve our understanding of the oceans and its responses to environmental changes.

An important phytoplankton group that we study in the lab are the coccolithophores, which constitute an ancient lineage that emerged in the late Triassic (~225 Million years ago) and today comprise over 200 species worldwide distributed. Characteristically, coccolithophore cells are covered to beautifully ornamented scales made of calcium carbonate, named coccoliths. Coccolithophores are of remarkable interest to a wide range of scientists. For marine biologists, they are among the main primary producers, and play a distinct role in oceanic ecosystems. For biogeochemists, they are significant in the global Carbon and Sulphur cycles contributing to the long-term storage of export of organic and inorganic carbon to the deep-ocean and ocean-atmosphere gas exchanges. For paleontologists and geologists, the remarkably continuous coccolithophore fossil record makes them ideal tools for biostratigraphy and paleoceanography studies.

Remarkably, coccolithophores possess complex sexual life cycles is composed to 2 morphologically distinct phases, one haploid and the other diploid. Currently little is known about the significance of such biphasic life cycle. Why coccolithophores have consistently 2 life cycle phases? What is the functional role and impact of each phase in the ecosystem? What are the triggers that mediate life phase transition? How is it regulated at the molecular level? These are some of the main questions we address in the lab…

The figure above, depicts the coccolithophore Pontosphera japonica collected in the Mediterranean sea that is undergoing life cycle phase transition. Such transtions can be detected as the cells carries 2 types of coccoliths, smaller holococcoliths that are typical of haploid cells (top left) and larger heterococcoliths that are typical of diploid cells (top right). (Frada et a. 2009).

Education

2005-2009       PhD, University Pierre and Marie Curie (France) - Marine Sciences

1998-2002       B.Sc., University of Azores (Portugal) - Biology

Professional Positions

2011-2015       Postdoctoral Associate, Weizmann Institute of Science (Israel) - Marine Microbiology, Cell Biology.

2009-2011       Postdoctoral Associate, Institute of Marine and Coastal Sciences, Rutgers University (USA) – Marine Microbiology, Biochemistry.

2004-2005       Research assistant, Institute of Marine and Coastal Sciences, Rutgers University (USA) – Marine Ecology.

2002-2003       Research assistant, University of Azores (Portugal) – Microbiology.

Current Members

Past Members