PDF file: EURASNET Annual Report 2008

Participant 25 - James SteveninWP 7. We have shown that the last exon of SC35 pre-mRNA is responsible for a negative retro-controlof SC35 production at the splicing step. The regulation occurs at the level of alternative splicing, theinvolvement of 2 kinds of trans-acting factors with opposite activities (SC35 as a positive factor andhnRNP H and TDp43 as negative factors) allowing the production of various mRNA isoforms ofdifferent stabilities. In collaboration with the group 12c, (C. Branlant), we also determinedexperimentally the secondary structure of the evolutionary conserved regulatory region in this SC35terminal exon. This opened the possibility to identify the binding sites for regulatory proteins (seedeliverable 166).WP 14. We had previously validated specific extracts from human cells overexpresssing various SR orTra2 proteins to analyse splicing of LMNA transcripts, in collaboration with Jamal Tazi’s group. Wehave used now such extracts to reveal some RNA-proteins interactions with specific regions of LMNAgene, under ithe wild type or mutated formsWP 12. We have further characterized the alternate binding of splicing regulators to the region ofLMNA transcripts, which is mutated in HGP Progeria patient, leading to the use of a cryptic 5' splicesite within exon 11. Using a slightly different approach, they have confirmed results obtained byPartner 12c (Christiane Branlant), especially the disruption of an ASF/SF2 binding site in mutanttranscripts. Using a specific in vitro assay developed in the lab to monitor LMNA exon 11 splicing,they will now analyse whether this factor may or not repress the use of the cryptic site in wild-typetranscripts.In collaboration with A. Martins et M. Tosi (INSERM, Rouen, France), we have also looked for factorsthat bind differentially to wild-type MSH2 exon 5 and MLH1 exon 10 versus mutant exons fromHNPCC patients (hereditary nonpolyposis colorectal cancer). Several factors (SR and hnRNP proteins)have been found and our collaborators will now study their involvement using in vitro and in vivominigene assays.b) Major cost items with justificationMajor cost itemsParticipant 1A Type of expenditure Budget total costspersonnel 45573.68consumables 0training 0equipment 0travel 2027.86= total direct costs 47499.68+ overhead 8549.94Adjustment on previous -3725.84= total eligible costs 52323.78• ResearchPersonnelNatacha Dreumont [WP 7,12,14 ] 1470 hours 45573.68 EuroTravel (2027.86 Euros)Stevenin James : 20-23.01.2008 Mission to Eurasnet Meeting, Berlin, GermanyStevenin James : 21-25.05.08 Mission to “International Eurasnet Alternative SplicingConference” Krakow, Poland, France (Inscription Flight, Parking etc)Bourgeois Cyril : 21-25.05.08 Mission to “International Eurasnet AlternativeSplicing Conference” Krakow, Poland, France (Inscription Flight, Parking, etc)184