Abstract EN:

TFIIH is a factor involved in transcription, cell cycle and DNA repair. It consists of ten subunits organized in two sub-complexes, the core and the CAK. During transcription elongation, the RNA POLII carboxy-terminal domain phosphorylation by TFIIH plays a role in transcription of protein coding and snRNA genes. First, our study consisted to identify the transient interacting proteins of the core using TAP tag strategy and to dissect the protein interacting domains within the core. The purification of the endogenous core required the technological development of TAP tag. Our first results suggest that adaptations will be necessary to purify the core with transient partners. The interaction studies showed the role of C-terminus domain of p34 in the core stability. Secondly, we used a comparative genomics approach consisting to establish the phylogenetic distribution of the core-TFIIH subunits in eukaryotes and to construct a multiple alignment of complete sequences (MACS) for each subunit. Our results revealed the core conservation in eucaryotes except in few protists. The MACS analysis exhibits the lost of p62 PH domain in E. Histolytica and the sequence divergences within p34 family in Euglenozoae. To get insights into p62 and p34 function, we used the phylogenetic profile methods. First, our results revealed that the gene sets sharing Tfb1 distribution is enriched in genes involved in histones modifications such Bre1and Set 1 and suggest a link between p62 and transcription activation. Secondly,they showed that the genes set sharing Tfb4 profile exhibits enrichment in genes of splicing and capping, suggesting a link between the core and the pre-mRNA processing.