Objectif The "Pre-messenger RNA maturation" network already includes 6 participants who are studying the basic mechanism of spliceosome assembly and function, in vertebrate species and ln the yeast S. cerevisiae. Although displaying common properties, the plant splicing machinery differs in several aspects, so that, only some of the vertebrate introns can be spliced in plants and plant in vitro splicing systems have not been developped, yet. Thus, a lot has to be done to characterize and understand the plant splicing machinery. Participant 7, F.Solymosy has a long expertise in plant UsnRNAs studies, including Chlamydomonas reinhardtii UsnRNAs. He is the international specialist in the field. C.reinhardtii represents an interesting system on a phylogenetic point of view, but also, as it can be easily transformed. The goal will be to join the expertise of the actual members of the network with that of F. Solymosy, to progress in the understanding of the plant splicing machinery: authentic plant UsnRNAs will be produced, as well as chimeric RNAs containing parts of plant UsnRNAs and parts of vertebrate UsnRNAs. Their capacity to complement HeLa cells nuclear extracts depleted of one of the UsnRNA will be tested. Work will be achieved in order to try to purify and study plant UsnRNPs, purified UsnRNPs will also be used in complementation assays and their composition and structure will be studied. Splicing of nuclear pre-messenger RNA usually fits the GT/AG rule for the donor and acceptor sites, respectively. A few introns do not obey to this rule and I. Kiss (participant 8) is among those scientists who found such exception in the gene coding for chicken cartilage matrix protein (CMP). It will be very interesting to study how such splicing can occur, does it occur in usual or unusual spliceosome ? Here again joining the expertise of the 6 members of the actual network, with that of I. Kiss, should permit to solve this problem. In addition, participant 8, also found alternative splicing in the 5' untranslated region of the chicken LP mRNA and it will be interesting to study the molecular basis of the alternative splicing choices, using the expertise of other members of the network. Altogether, alternative splicing and unusual splicing probably play an important role in differenciation and development. This aspect was not studied up to now in the network, the integration of participant 8, will be important to introduce it. Programme(s) IC-PECO/COPERNICUS - Scientific and technological cooperation between the European Community and European non-member countries, 1992- Thème(s) 0401 - CEEC participation in HUMAN CAPITAL & MOBILITY programme (NETWORKS) Appel à propositions Data not available Régime de financement CSC - Cost-sharing contracts Coordinateur Centre National de la Recherche Scientifique Contribution de l’UE Aucune donnée Adresse Boulevard des Aiguillettes 54506 Vandoeuvre-les-Nancy France Voir sur la carte Coût total Aucune donnée Participants (2) Trier par ordre alphabétique Trier par contribution de l’UE Tout développer Tout réduire Biological Research Centre - Hungarian Academy of Sciences Hongrie Contribution de l’UE Aucune donnée Adresse 6701 Szeged Voir sur la carte Coût total Aucune donnée Biological Research Centre - Hungarian Academy of Sciences Hongrie Contribution de l’UE Aucune donnée Adresse 62,Temesvari 6726 Szeged Voir sur la carte Coût total Aucune donnée