Our research is centered on two major questions: How does a single genome sequence encode the information to build the enormous complexity of cell types and structures of an adult organism? How are changes in this sequence translated into morphological novelties during evolution? We approach these topics focusing on cell and tissue type specific transcriptomes: How are they encoded in the genome? How are they generated during embryogenesis? How do they impact cell function in adult organisms? How do they evolve and how they impact evolution? What are their pathological implications? To answer these questions, we not only study transcriptional regulation, but also other mechanisms that expand transcriptomic diversity, such as alternative splicing and gene duplication.