Aplicación de la Bioquímica y Biología Molecular en el Grado de Enfermería a través del aprendizaje basado en problemas

El CMD docente (CMD) se ha realizado en la asignatura de 1er curso “Bioquímica y Biología Molecular”. Se ha desarrollado incluyendo el temario correspondiente al bloque de Proteínas. Han participado 56 estudiantes. El trabajo se ha realizado, inicialmente individual y fuera del aula, aunque algunos optaron por hacerlo conjunto, en subgrupos y con un aprendizaje colaborativo. Se han empleado los mapas de contenidos y se ha evaluado el CMD mediante el uso de escaleras de aprendizaje. Los resultados muestran, en general, una adquisición adecuada de los conocimientos trabajados y han sido bastante satisfactorios para el alumnado

Control of the function of the transcription and repair factor TFIIH by the action of the cochaperone Ydj1

Yeast rad3-102, a mutant of the TFIIH complex involved in nucleotide excision repair (NER) and transcription, can perform NER initial steps but not late steps of postincision gap filing. Because removal of early-acting NER proteins prevents rad3-102 deleterious action, we used this feature to explore if chaperones act in early NER. We found that the cochaperone Ydj1 is required for NER and that Ydj1 guarantees TFIIH stoichiometry. Importantly, in the absence of Ydj1, the roles of TFIIH in transcription and transactivation, the ability to activate transcription by nuclear receptors in response to hormones, are strongly impaired. We propose that TFIIH constitutes a multitarget complex for Ydj1, as six of the seven TFIIH core components contain biologically relevant Ydj1- binding motives. Our results provide evidence for a role of chaperones in NER and transcription, with implications in cancer and TFIIH-associated syndromes

Control of the function of the transcription and repair factor TFIIH by the action of the cochaperone Ydj1

Yeast rad3-102, a mutant of the TFIIH complex involved in nucleotide excision repair (NER) and transcription, can perform NER initial steps but not late steps of postincision gap filing. Because removal of early-acting NER proteins prevents rad3-102 deleterious action, we used this feature to explore if chaperones act in early NER. We found that the cochaperone Ydj1 is required for NER and that Ydj1 guarantees TFIIH stoichiometry. Importantly, in the absence of Ydj1, the roles of TFIIH in transcription and transactivation, the ability to activate transcription by nuclear receptors in response to hormones, are strongly impaired. We propose that TFIIH constitutes a multitarget complex for Ydj1, as six of the seven TFIIH core components contain biologically relevant Ydj1- binding motives. Our results provide evidence for a role of chaperones in NER and transcription, with implications in cancer and TFIIH-associated syndromes

Conditional Expression of RNase P in the CyanobacteriumSynechocystis sp. PCC6803 Allows Detection of Precursor RNAs

We have constructed a strain (CT1) that expresses RNase P conditionally with the aim to analyze the in vivotRNA processing pathway and the biological role that RNase P plays inSynechocystis 6803. In this strain, the rnpBgene, coding for the RNA subunit of RNase P, has been placed under the control of the petJ gene promoter (PpetJ), which is repressed by copper, cell growth, and accumulation of RNase P RNA is inhibited in CT1 after the addition of copper, indicating that the regulation by copper is maintained in the chimerical PpetJ -rnpB gene and that RNase P is essential for growth in Synechocystis. We have analyzed several RNAs by Northern blot and primer extension in CT1. Upon addition of copper to the culture medium, precursors of the mature tRNAs are detected. Furthermore, our results indicate that there is a preferred order in the action of RNase P when it processes a dimeric tRNA precursor. The precursors detected are 3′-processed, indicating that 3′ processing can occur before 5′ processing by RNase P. The size of the precursors suggests that the terminal CCA sequence is already present before RNase P processing. We have also analyzed other potential RNase P substrates, such as the precursors of tmRNA and 4.5 S RNA. In both cases, accumulation of larger than mature size RNAs is observed after transferring the cells to a copper-containing medium

The Rad50 coiled-coil domain is indispensable for Mre11 complex functions

The Mre11 complex (Mre11, Rad50 and Xrs2 in Saccharomyces cerevisiae) influences diverse functions in the DNA damage response. The complex comprises the globular DNA-binding domain and the Rad50 hook domain, which are linked by a long and extended Rad50 coiled-coil domain. In this study, we constructed rad50 alleles encoding truncations of the coiled-coil domain to determine which Mre11 complex functions required the full length of the coils. These mutations abolished telomere maintenance and meiotic double-strand break (DSB) formation, and severely impaired homologous recombination, indicating a requirement for long-range action. Nonhomologous end joining, which is probably mediated by the globular domain of the Mre11 complex, was also severely impaired by alteration of the coiled-coil and hook domains, providing the first evidence of their influence on this process. These data show that functions of Mre11 complex are integrated by the coiled coils of Rad50.Swiss National Science Foundation and Eugen and Elisabeth Schellenberg Foundation GM56888, PBZH33-112756, PA0033-117484Ministerio de Ciencia e Innovación BFU2006-05260, 2010 CSD2007-01

Mutation in ROBO3 Gene in Patients with Horizontal Gaze Palsy with Progressive Scoliosis Syndrome: A Systematic Review

Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare, inherited disorder characterized by a congenital absence of conjugate horizontal eye movements with progressive scoliosis developing in childhood and adolescence. Mutations in the Roundabout (ROBO3) gene located on chromosome 11q23-25 are responsible for the development of horizontal gaze palsy and progressive scoliosis. However, some studies redefined the locus responsible for this pathology to a 9-cM region. This study carried out a systematic review in which 25 documents were analyzed, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. The search was made in the following electronic databases from January 1995 to October 2019: PubMed, Scopus, Web of Science, PEDRO, SPORT Discus, and CINAHL. HGPPS requires a multidisciplinary diagnostic approach, in which magnetic resonance imaging might be the first technique to suggest the diagnosis, which should be verified by an analysis of theROBO3 gene. This is important to allow for adequate ocular follow up, apply supportive therapies to prevent the rapid progression of scoliosis, and lead to appropriate genetic counseling

Architecture and nucleic acids recognition mechanism of the THO complex, an mRNP assembly factor

The THO complex is a key factor in co-transcriptional formation of export-competent messenger ribonucleoprotein particles, yet its structure and mechanism of chromatin recruitment remain unknown. In yeast, this complex has been described as a heterotetramer (Tho2, Hpr1, Mft1, and Thp2) that interacts with Tex1 and mRNA export factors Sub2 and Yra1 to form the TRanscription EXport (TREX) complex. In this study, we purified yeast THO and found Tex1 to be part of its core. We determined the three-dimensional structures of five-subunit THO complex by electron microscopy and located the positions of Tex1, Hpr1, and Tho2 C-terminus using various labelling techniques. In the case of Tex1, a β-propeller protein, we have generated an atomic model which docks into the corresponding part of the THO complex envelope. Furthermore, we show that THO directly interacts with nucleic acids through the unfolded C-terminal region of Tho2, whose removal reduces THO recruitment to active chromatin leading to mRNA biogenesis defects. In summary, this study describes the THO architecture, the structural basis for its chromatin targeting, and highlights the importance of unfolded regions of eukaryotic proteins.Ministerio de Ciencia e Innovación BFU2010- 15703/BMC, BFU2006-0526

Mutation in ROBO3 Gene in Patients with Horizontal Gaze Palsy with Progressive Scoliosis Syndrome: A Systematic Review

Horizontal gaze palsy with progressive scoliosis (HGPPS) is a rare, inherited disorder characterized by a congenital absence of conjugate horizontal eye movements with progressive scoliosis developing in childhood and adolescence. Mutations in the Roundabout (ROBO3) gene located on chromosome 11q23–25 are responsible for the development of horizontal gaze palsy and progressive scoliosis. However, some studies redefined the locus responsible for this pathology to a 9-cM region. This study carried out a systematic review in which 25 documents were analyzed, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. The search was made in the following electronic databases from January 1995 to October 2019: PubMed, Scopus, Web of Science, PEDRO, SPORT Discus, and CINAHL. HGPPS requires a multidisciplinary diagnostic approach, in which magnetic resonance imaging might be the first technique to suggest the diagnosis, which should be verified by an analysis of the ROBO3 gene. This is important to allow for adequate ocular follow up, apply supportive therapies to prevent the rapid progression of scoliosis, and lead to appropriate genetic counseling