| Speaker: |
Manuel Irimia
University of Barcelona, Department of Genetics |
| Title: |
Stepwise Assembly of a Tissue-specific Network in the Vertebrate Brain |
| Summary : | Understanding the emergence of complex biological functions requires characterizing the assembly of the molecular networks underlying these functions. Nova is a splicing factor specifically expressed in vertebrate brains, where it regulates a variety of genes involved in synapse function and axon guidance. By binding to position-dependent sequence motifs in pre-mRNAs, Nova differentially inhibits or encourages the inclusion of a set of exons in neuron-expressed transcripts with respect to transcripts from the same genes expressed in non-neural tissues. We sought to investigate the origin of the vertebrate Nova network by studying, in key invertebrate species: (i) conservation of the molecular mechanism of Nova splicing regulation, (ii) conservation of central nervous system-specific developmental expression, and (iii) presence of exons and signals targeted by Nova in vertebrates. We find that brain-specific Nova network is a vertebrate novelty, and reconstruct the step-by-step emergence of this network. In addition, we find widely varied Nova expression patterns across metazoans, and particularly different tissue-specific expression in multiple lineages, suggesting parallel assembly and elaboration of Nova-regulated networks in diverse metazoans. |
