Non-coding RNA, epigenetics and genome stability

Genome dynamics

 

The sequencing of many different eukaryotic genomes revealed that genes represent only a small part of each genome compared with intergenic and repeated sequences (e.g. satellites, microsatellites, transposable elements). For instance, up to 45% of the human genome consists of transposable elements (TEs). Active TEs are able to replicate by inserting new copies elsewhere in the host genome, which can dramatically impact genome structure and function. However, diverse defense mechanisms (including piRNA-mediated transcriptional silencing) restrain mobilization of integrated TEs to low levels compatible with host survival. Indeed, depending on their insertion site, TEs can lead to the destruction, inactivation, or deregulation of coding genes. TEs can also affect the epigenetic landscape in the vicinity of the insertion site and the three-dimensional (3D) chromatin structure. Moreover, TE sequences are able to recruit the host transcription machinery to express their own products and promote transposition. This capacity is kept long after they have lost the ability to transpose, suggesting that TEs have significantly contributed to the evolution of transcription regulation. Indeed, selection tends to co-opt positive insertions and eliminate harmful insertions. Altogether, this gives rise to a delicate equilibrium which, when disrupted, leads to pathologies or sterility (when germ cells are concerned by transposition). 

The three following projects aim to understand these genetic conflicts and their eventual resolution at both the lab and evolutionary time scales

Project 1 : What are the impacts of TE insertions on the genome structure and function?

Project 2 : What are the transcriptional roles of piRNAs on TEs and piRNA source loci ?

Project 3 : What are the chromatin effectors of TE transcriptional repression ?

 

 

Severine CHAMBEYRON
Researcher

0434359944
Charlotte GRIMAUD
Researcher

0434359948
Alain PELISSON
Researcher

0434359948
Marion Varoqui
Marion VAROQUI
PhD Student

0434359949
Maelys Lemoine
Maelys LEMOINE
ITA

0434359944
Maelys Lemoine
Maelys LEMOINE
ITA

0434359944
Mourdas MOHAMED
Ingénieur d'étude en bio-informatique
ITA

0434359944
Bruno MUGAT
Gestionnaire parc binoculaires et injection
ITA

0434359949

Publications of the team

A Transposon Story: From TE Content to TE Dynamic Invasion of Drosophila Genomes Using the Single-Molecule Sequencing Technology from Oxford Nanopore

Mourdas Mohamed, Nguyet Thi-Minh Dang, Yuki Ogyama, Nelly Burlet, Bruno Mugat, Matthieu Boulesteix, Vincent Mérel, Philippe Veber, Judit Salces-Ortiz, Dany Severac, Alain Pélisson, Cristina Vieira, François Sabot, Marie Fablet, Séverine Chambeyron

more

The Mi-2 nucleosome remodeler and the Rpd3 histone deacetylase are involved in piRNA-guided heterochromatin formation

Bruno Mugat, Simon Nicot, Carolina Varela-Chavez, Christophe Jourdan, Kaoru Sato, Eugenia Basyuk, François Juge, Mikiko C. Siomi, Alain Pélisson & Séverine Chambeyron

more

The somatic piRNA pathway controls germline transposition over generations.

Barckmann B, El-Barouk M, Pélisson A, Mugat B, Li B, Franckhauser C, Fiston Lavier AS, Mirouze M, Fablet M, Chambeyron S

Transposable Element Misregulation Is Linked to the Divergence between Parental piRNA Pathways in Drosophila Hybrids

Romero-Soriano V, Modolo L, Lopez-Maestre H, Mugat B, Pessia E, Chambeyron S, Vieira C, Garcia Guerreiro MP

Piwi Is Required during Drosophila Embryogenesis to License Dual-Strand piRNA Clusters for Transposon Repression in Adult Ovaries

Akkouche, A., Mugat, B., Barckmann, B., Varela-Chavez, C., Li, B., Raffel, R., Pelisson, A., Chambeyron, S.

Identification of misexpressed genetic elements in hybrids between Drosophila-related species

Lopez-Maestre H, Carnelossi EA, Lacroix V, Burlet N, Mugat B, Chambeyron S, Carareto CM, Vieira C

Aubergine iCLIP Reveals piRNA-Dependent Decay of mRNAs Involved in Germ Cell Development in the Early Embryo

Barckmann,B., Pierson,S., Dufourt, J., Papin, C., Armenise, C., Port, F., Grentzinger, T., Chambeyron, S., Baronian, G., Desvignes, JP., Curk, T., Simonelig, M.


+ mRNA Regulation and Development

MicroRNA-Dependent Transcriptional Silencing of Transposable Elements in Drosophila Follicle Cells

Mugat B, Akkouche A, Serrano V, Armenise C, Li B, Brun C, Fulga TA, Van Vactor D, Pélisson A, Chambeyron S

A user-friendly chromatographic method to purify small regulatory RNAs

Grentzinger T, Armenise C, Pelisson A, Brun C, Mugat B, Chambeyron S.

Fast and Accurate Method to Purify Small Noncoding RNAs from Drosophila Ovaries

Grentzinger T, Chambeyron S.

A user-friendly chromatographic method to purify small regulatory RNAs

Grentzinger T, Armenise C, Pelisson A, Brun C, Mugat B, Chambeyron S

Epigenetics and transgenerational inheritance

Brasset E, Chambeyron S.

Maternally deposited germline piRNAs silence the tirant retrotransposon in somatic cells

Akkouche A, Grentzinger T, Fablet M, Armenise C, Burlet N, Braman V, Chambeyron S. §, Vieira C§ (co-dernier auteur)

piRNA-mediated transgenerational inheritance of an acquired trait

Grentzinger T, Armenise C, Brun C, Mugat B, Serrano V, Pelisson A, Chambeyron S.

Thèses et hdr

Study of the impact of loss of repression of endogenous retroviruses on genome integrity in Drosophila 16/12/2016

BASYUK Eugenia
BASYUK Eugenia
Chercheur
AKKOUCHE Abdou
AKKOUCHE Abdou
Chercheur
NICOT Simon
NICOT Simon
Chercheur
SERRANO Vincent
SERRANO Vincent
Chercheur
VARELA CHAVEZ Carolina
VARELA CHAVEZ Carolina
Chercheur
EL BAROUK Marianne
EL BAROUK Marianne
Doctorant
GRENTZINGER Thomas
GRENTZINGER Thomas
Doctorant
LUGAGNE Anais
LUGAGNE Anais
Doctorant
ARMENISE Claudia
ARMENISE Claudia
ITA
AUDOUIN Katell
AUDOUIN Katell
ITA
BARCKMANN Bridlin
BARCKMANN Bridlin
ITA
GUERY Melodie
GUERY Melodie
ITA
GUILLAUME Mickael
GUILLAUME Mickael
ITA
JOURDAN Christophe
JOURDAN Christophe
ITA
LI Blaise
LI Blaise
ITA
MOHAMED Mourdas
MOHAMED Mourdas
ITA
MOHAMED Mourdas
MOHAMED Mourdas
ITA