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Molecular mechanisms for the evolution of multicellularity in animals


The evolution of multicellular animals (metazoans) from a unicellular ancestor is one of the most significant leaps in the history of life. However, little is known about the mechanisms that enabled it. Upon the acquisition of multicellularity, many molecular level innovations should have occurred, especially in the systems responsible for cell adhesion, differentiation, and cell-cell communication. Investigation of a group of protists (unicellular or colonial eukaryotes) that is closely related to metazoans should provide deep insights into molecular mechanisms for this event. Among such protists, however, only unicellular choanoflagellates have been extensively studied so far. This project aims to fill this missing piece by applying comparative genomics and molecular biological approaches to Codonosiga botrytis, a colonial choanoflagellate and two additional protists Sphaeroforma arctica and Capsaspora owczarzaki, which were recently shown to be closely related to metazoans, like choanoflagellates. To this aim, 1) the complete genome sequences of Sphaeroforma and Capsaspora, which will be exclusively available in the host institute, will be analyzed and compared to those of metazoans, in order to identify the candidate genes that were relevant to the evolution of multicellularity. Then 2) the difference in the expression profiles between the colonial and unicellular stages of Sphaeroforma and Codonosiga will be studied to identify genes responsible for forming the colony, which might represent the ‘ancestral form’ of multicellularity in metazoans. Finally, 3) molecular biological methods will be developed and applied to these protists, and functions of the candidate genes identified in 1) and 2) will be analyzed. This should elucidate the functional ‘innovations’ that enabled the evolution of multicellularity. These data will have a major impact to a wide range of research fields, especially to the ‘evo-devo’, microbiology, and molecular evolution communities.

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Gran via de les corts catalanes 585
08007 Barcelona

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Este Cataluña Barcelona
Activity type
Higher or Secondary Education Establishments
Administrative Contact
Iñaki Ruiz-Trillo (Dr.)
EU contribution
€ 218 164,02