Search

For twenty years, the psychotherapeutic field in France, England and the Netherlands, has undergone significant transformations in relation to methods and professionals groups. In a socio-historical perspective, this paper brings describes three stages: in the 1960s and 1970s the formation of a specific psychotherapeutic field in these three countries, sharing a similar processes of extension and psychologization of psychotherapy; throughout the 1980s and 1990s, common mental health disorders which became mass disorders, have been elaborated as a public health priority with the influence of European policies since the 2000s; finally, psychotherapy has been redefined in a context that now emphasises evidence-based interventions that enhance psychosocial capacities and give precedence to Cognitive-Behavioural Therapies. While similar trends are observed in these countries, national characteristics nonetheless remain strong.

Since the majority of protein-coding genes in vertebrates have intra-genomic homologues, it has been difficult to eliminate the potential of functional redundancy from analyses of mutant phenotypes, whether produced by genetic lesion or transient knockdown. Further complicating these analyses, not all gene products have activities that can be assayed in vitro, where the efficiency of the various family members can be compared against constant substrates. Two vertebrate UNC-45 homologues, unc45a and unc45b, affect distinct stages of muscle differentiation when knocked down in cell culture and are functionally redundant in vitro. UNC-45 proteins are members of the UCS (UNC-45/CRO1/She4p) protein family that has been shown to regulate myosin-dependent functions from fungi to vertebrates through direct interaction with the myosin motor domain. To test whether the same functional relationship exists between these unc45 paralogs in vivo, we examined the developmental phenotypes of doubly homozygous unc45b(-/-); unc45a(-/-) mutant zebrafish embryos. We focused specifically on the combined effects on morphology and gene expression resulting from the zygotic lack of both paralogs. We found that unc45b(-/-) and unc45b(-/-); unc45a(-/-) embryos were phenotypically indistinguishable with both mutants displaying identical cardiac, skeletal muscle, and jaw defects. We also found no evidence to support a role for zygotic Unc45a function in myoblast differentiation. In contrast to previous in vitro work, this rules out a model of functional redundancy between Unc45a and Unc45b in vivo. Instead, our phylogenetic and phenotypic analyses provide evidence for the role of functional divergence in the evolution of the UCS protein family.