Studying essential DNA metabolism proteins in Xenopus egg extract

The correct duplication of genetic information is essential to maintain genome stability, which is lost in cancer cells. Replication fork integrity is ensured by a number of DNA metabolism proteins that assist replication of chromatin regions difficult to replicate due to their intrinsic DNA sequence composition, coordinate repair of DNA molecules resulting from aberrant replication events or protect replication forks in the presence of lesions impairing their progression. Some DNA metabolism genes involved in DNA repair are essential in higher eukaryotes even in unchallenged conditions, suggesting the existence of biological processes requiring these specialized functions in organisms with complex genomes. The impact on cell survival of null mutants of many DNA metabolism genes has precluded complete in depth analysis of their function. Cell free extracts represent a fundamental tool to overcome survival issues. The Xenopus laevis egg cell free extract is an ideal system to study replication-associated functions of essential genes. We are taking advantage of this system together with innovative imaging and proteomic based experimental approaches to characterize the molecular function of essential DNA metabolism proteins. Using this approach we have uncovered the role of some essential homologous recombination and fork protection proteins in chromosomal DNA replication and we have characterized some of the factors required for faithful replication of specific vertebrate genomic regions. This approach will be instrumental to study the molecular mechanisms underlying the function of a number of essential DNA metabolism proteins involved in the maintenance of genome stability in complex genomes

Moonlighting at replication forks - a new life for homologous recombination proteins BRCA1, BRCA2 and RAD51

Coordination between DNA replication and DNA repair ensures maintenance of genome integrity, which is lost in cancer cells. Emerging evidence has linked homologous recombination (HR) proteins RAD51, BRCA1 and BRCA2 to the stability of nascent DNA. This function appears to be distinct from double-strand break (DSB) repair and is in part due to the prevention of MRE11-mediated degradation of nascent DNA at stalled forks. The role of RAD51 in fork protection resembles the activity described for its prokaryotic orthologue RecA, which prevents nuclease-mediated degradation of DNA and promotes replication fork restart in cells challenged by DNA-damaging agents. Here, we examine the mechanistic aspects of HR-mediated fork protection, addressing the crosstalk between HR and replication proteins

Conflicting values in designing adaptive reuse for cultural heritage. A case study of social multicriteria evaluation

Over the past two decades the Council of Europe has addressed cultural heritage preservation policies to the use of heritage as cultural capital. Given this definition, the conservation of cultural capital is crucial, for its intrinsic value and as an investment for cultural, social and economic development. Thus, principles and areas of actions have been defined with the aim of underlying the importance of cultural values for territorial identity. Especially for cultural heritage with a potential for tourism, the decisions about valorization interventions are not always consensual, given the coexistence of different instances from local inhabitants and tourists. Selecting among the potential uses the one that could ensure the preservation of physical characters as well as intangible values, fueling economic development, is still a challenging policy and design issue. In this context, this paper proposes the use of a multi-methodological approach based on Choice Experiments and Social Multicriteria Evaluation to support the adaptive reuse on real case study. The NAIADE approach has allowed the decision maker to consider both socio-economic and technical dimensions within the same evaluation framewor