Professor Paul Lefebvre

These researchers are studying the assembly and function of the basal bodies and flagella of the unicellular green alga Chlamydomonas reinhardtii. Chlamydomonas is the premier model system for the dissection of the molecular mechanisms regulating the assembly and function of the cilia and flagella of eukaryotes. Now that the sequence of the genome has been obtained, and the molecular map of the genome has been completed, these researchers are seeking to elucidate the mechanisms that control the assembly and functioning of cilia and flagella. To this end they are applying a newly developed insertional mutagenesis approach which, in combination with tail-PCR procedures, allows them to rapidly clone genes mutated by the insertion of a selectable marker gene by transformation. Initially they are focusing their efforts on two classes of genes. First, they are seeking to understand the control of flagellar assembly by cloning and characterizing all genes involved in the regulation of flagellar length. Second, they are seeking to understand how the basal bodies subtending the flagella are regulated by studying mutants with defective control of flagellar number. For these experiments MSI resources are invaluable for analyzing the predicted proteins from the cloned genes, for analyzing the genes in the context of the whole genome, and for comparing the predicted protein sequences from Chlamydomonas with homologous proteins from other eukaryotic organisms. In addition, image deconvolution software available at MSI allows the group to obtain high quality images of the structures of in flagella and basal bodies.