Msh2 Blocks an Alternative Mechanism for Non-Homologous Tail Removal during Single-Strand Annealing in Saccharomyces cerevisiae

Chromosomal translocations are frequently observed in cells exposed to agents that cause DNA double-strand breaks (DSBs), such as ionizing radiation and chemotherapeutic drugs, and are often associated with tumors in mammals. Recently, translocation formation in the budding yeast, Saccharomyces cerevisiae, has been found to occur at high frequencies following the creation of multiple DSBs adjacent to repetitive sequences on non-homologous chromosomes. The genetic control of translocation formation and the chromosome complements of the clones that contain translocations suggest that translocation formation occurs by single-strand annealing (SSA). Among the factors important for translocation formation by SSA is the central mismatch repair (MMR) and homologous recombination (HR) factor, Msh2. Here we describe the effects of several msh2 missense mutations on translocation formation that suggest that Msh2 has separable functions in stabilizing annealed single strands, and removing non-homologous sequences from their ends. Additionally, interactions between the msh2 alleles and a null allele of RAD1, which encodes a subunit of a nuclease critical for the removal of non-homologous tails suggest that Msh2 blocks an alternative mechanism for removing these sequences. These results suggest that Msh2 plays multiple roles in the formation of chromosomal translocations following acute levels of DNA damage

As contribuições da ciência do desenvolvimento para a psicologia da saúde The contributions of developmental science to the health psychology

A ciência do desenvolvimento humano vem estimulando uma nova visão sobre a pesquisa em saúde, destacando variáveis contextuais e ecológicas que influenciam o processo de desenvolvimento e condicionam o diagnóstico, o tratamento e o prognóstico de indivíduos e grupos. O objetivo deste artigo é discutir as implicações da ciência do desenvolvimento humano à psicologia da saúde, área de intervenção educacional voltada aos diversos contextos de tratamento de saúde. Pretende-se, ainda, analisar criticamente alguns aspectos metodológicos dos estudos da área e apontar tendências atuais e futuras para uma análise mais funcional do processo saúde-doença. Espera-se que os profissionais de saúde se beneficiem dos argumentos e modelos propostos pela ciência do desenvolvimento humano, construindo ambientes de cuidados mais adequados às necessidades psicossociais de pacientes e familiares.<br>The science of human development has been stimulating a new perspective on health research, highlighting contextual and ecological variables that influence the process of development and condition the diagnosis, treatment and prognosis of individuals and groups. The objective of this article is to discuss about the implications of the science of human development for health psychology, specifically for the educational area aimed toward intervention in several contexts of health treatment. Another objective of this article is to critically analyze some methodological aspects os the studies in this area and point current and future tendencies at a more functional analysis of the health-disease process. It is expected that health professionals benefit from the arguments and models proposed by the science of human development, designing environments that are more adequate to the psychological needs of patients and families

Electroporation: an arsenal of application

Electroporation is a way to induce nanometersized membrane pore for exogenous substances delivery into cytoplasm using an artificial electric field. Now it was widely used for molecules transfer especially in molecular experiments and genetic aspects. In recent years, modern electroporation on the embryo was developed, whose most important point is that it adopts low energy and rectangular pulse that could obtain high transfection efficiency and low damage to the embryo. This paper reviewed on the pool of application: from lab works to human clinical treatments