Evolution and Development of Germ Cells
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Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, Inserm U1050, Université Paris Sciences & Lettres (PSL)
11 place Marcelin Berthelot
F-75005 Paris, France
Scientific Interest
Transposable elements (TEs) make up half of our genome and induce DNA damages when active. In recent years, an adaptive immune system protecting the genome against these types of threats has been uncovered. This genome immune system is based on small non-coding RNAs, such as piRNAs, which can target other RNAs by base-pair complementarity. piRNAs are produced by discrete loci in the genome, called piRNA clusters, which constitute the memory of this immune system. Our global objective is to understand how this defense system can evolve and adapt to novel threats and external stresses, without targeting endogenous genes by autoimmunity. Our main hypothesis is that RNA fragments from tRNAs and DNA loci encoding for tRNA play major roles in the adaptability of genome defenses at both short and long term scales. We focus our studies on a temporal window of plasticity during the early stages of germ cells development, called the pilp (piwilesspocket). Our first objective is to examine piRNAs and tRNA fragments (tRFs) produced in the pilp and to understand how both piRNAs and tRFs cooperate in the pilp to adapt TEs repression on a short term. Our second objective is to test if tRNA loci (tDNA) can give rise to piRNA clusters and to characterize the cis and trans determinants of piRNA clusters activation.
Transposable elements (TEs) make up half of our genome and induce DNA damages when active. In recent years, an adaptive immune system protecting the genome against these types of threats has been uncovered. This genome immune system is based on small non-coding RNAs, such as piRNAs, which can target other RNAs by base-pair complementarity. piRNAs are produced by discrete loci in the genome, called piRNA clusters, which constitute the memory of this immune system. Our global objective is to understand how this defense system can evolve and adapt to novel threats and external stresses, without targeting endogenous genes by autoimmunity. Our main hypothesis is that RNA fragments from tRNAs and DNA loci encoding for tRNA play major roles in the adaptability of genome defenses at both short and long term scales. We focus our studies on a temporal window of plasticity during the early stages of germ cells development, called the pilp (piwilesspocket). Our first objective is to examine piRNAs and tRNA fragments (tRFs) produced in the pilp and to understand how both piRNAs and tRFs cooperate in the pilp to adapt TEs repression on a short term. Our second objective is to test if tRNA loci (tDNA) can give rise to piRNA clusters and to characterize the cis and trans determinants of piRNA clusters activation.
Thematic