20 research outputs found
RNomics: a computational search for box C/D snoRNA genes in the D. melanogaster genome.
Motivation: In eukaryotes, the family of non-coding RNA
genes includes a number of genes encoding small nucleolar
RNAs (mainly C/D and H/ACA snoRNAs), which act as
guides in the maturation or post-transcriptional modifications
of target RNA molecules. Since in Drosophila melanogaster
(Dm) only few examples of snoRNAs have been identified so
far by cDNA libraries screening, integration of the molecular
data with in silico identification of these types of genes could
throw light on their organization in the Dm genome.
Results: We have performed a computational screening of
the Dm genome for C/D snoRNA genes, followed by experimental validation of the putative candidates. Few of the
26 confirmed snoRNAs had been recognized by cDNA library
analysis. Organization of the Dm genome was also
found to be more variegated than previously suspected, with
snoRNA genes nested in both the introns and exons of
protein-coding genes. This finding suggests that the presence
of additional mechanisms of snoRNA biogenesis based
on the alternative production of overlapping mRNA/snoRNA
molecules.
Availability: Additional information is available at http://www.
bioinformatica.unito.it/bioinformatics/snoRNA
Complete atrioventricular canal
Complete atrioventricular canal (CAVC), also referred to as complete atrioventricular septal defect, is characterised by an ostium primum atrial septal defect, a common atrioventricular valve and a variable deficiency of the ventricular septum inflow. CAVC is an uncommon congenital heart disease, accounting for about 3% of cardiac malformations. Atrioventricular canal occurs in two out of every 10,000 live births. Both sexes are equally affected and a striking association with Down syndrome was found. Depending on the morphology of the superior leaflet of the common atrioventricular valve, 3 types of CAVC have been delineated (type A, B and C, according to Rastelli's classification). CAVC results in a significant interatrial and interventricular systemic-to-pulmonary shunt, thus inducing right ventricular pressure and volume overload and pulmonary hypertension. It becomes symptomatic in infancy due to congestive heart failure and failure to thrive. Diagnosis of CAVC might be suspected from electrocardiographic and chest X-ray findings. Echocardiography confirms it and gives anatomical details. Over time, pulmonary hypertension becomes irreversible, thus precluding the surgical therapy. This is the reason why cardiac catheterisation is not mandatory in infants (less than 6 months) but is indicated in older patients if irreversible pulmonary hypertension is suspected. Medical treatment (digitalis, diuretics, vasodilators) plays a role only as a bridge toward surgery, usually performed between the 3rd and 6th month of life
High-level expression of Aliciclobacillus acidocaldarius thioredoxin in Pichia pastoris and Bacillus subtilis
Thioredoxins are ubiquitous proteins which catalyze the reduction of disulfide bridges on target proteins and are involved in many cellular reactions. In a previous work, a thioredoxin from the thermophilic organism Aliciclobacillus acidocaldarius (Alitrx) was purified, characterized, and its gene expressed in Escherichia coli. In order to produce larger quantities of Alitrx, the protein has been expressed in the methylotrophic yeast Pichia pastoris and in the gram positive bacteria Bacillus subtilis. The growth conditions of strains showing high-level expression of Alitrx were optimized for both systems in shake-flask cultures. Active proteins were secreted in the culture media at a level of approximately 0.9 and 0.5 g/l, respectively, for P. pastoris and B. subtilis. The proteins were purified almost to homogeneity by a thermal precipitation procedure, with a 90-fold and 50-fold higher total yield with respect to that obtained with the same protein expressed in E. coli. The results indicate that either of these two systems could be utilized as a host for large-scale production of recombinant Alitrx
High-level expression of Aliciclobacillus acidocaldarius thioredoxin in Pichia pastoris and Bacillus subtilis.
Thioredoxins are ubiquitous proteins which catalyze the reduction of disulfide bridges on target proteins and are involved in many cellular reactions. In a previous work, a thioredoxin from the thermophilic organism Aliciclobacillus acidocaldarius (Alitrx) was purified, characterized, and its gene expressed in Escherichia coli. In order to produce larger quantities of Alitrx, the protein has been expressed in the methylotrophic yeast Pichia pastoris and in the gram positive bacteria Bacillus subtilis. The growth conditions of strains showing high-level expression of Alitrx were optimized for both systems in shake-flask cultures. Active proteins were secreted in the culture media at a level of approximately 0.9 and 0.5 g/l, respectively, for P. pastoris and B. subtilis. The proteins were purified almost to homogeneity by a thermal precipitation procedure, with a 90-fold and 50-fold higher total yield with respect to that obtained with the same protein expressed in E. coli. The results indicate that either of these two systems could be utilized as a host for large-scale production of recombinant Alitrx
A novel extracellular subtilisin-like protease from the hyperthermophile Aeropyrum pernix k1: biochemical properties, cloning and expression.
Meldonium improves Huntington’s disease mitochondrial dysfunction by restoring peroxisome proliferator-activated receptor γ coactivator 1α expression
\ua9 2018 Wiley Periodicals, Inc. Mitochondrial dysfunction seems to play a fundamental role in the pathogenesis of neurodegeneration in Huntington’s disease (HD). We assessed possible neuroprotective actions of meldonium, a small molecule affecting mitochondrial fuel metabolism, in in vitro and in vivo HD models. We found that meldonium was able to prevent cytotoxicity induced by serum deprivation, to reduce the accumulation of mutated huntingtin (mHtt) aggregates, and to upregulate the expression of peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in mHTT-expressing cells. The PGC-1α increase was accompanied by the increment of mitochondrial mass and by the rebalancing of mitochondrial dynamics with a promotion of the mitochondrial fusion. Meldonium-induced PGC-1α significantly alleviated motor dysfunction and prolonged the survival of a transgenic HD Drosophila model in which mHtt expression in the nervous system led to progressive motor performance deficits. Our study strongly suggests that PGC-1α, as a master coregulator of mitochondrial biogenesis, energy homeostasis, and antioxidant defense, is a potential therapeutic target in HD