Large-scale analysis of the yeast genome by transposon tagging and gene disruption

Economical methods by which gene function may be analysed on a genomic scale are relatively scarce. To fill this need, we have developed a transposon-tagging strategy for the genome-wide analysis of disruption phenotypes, gene expression and protein localization, and have applied this method to the large-scale analysis of gene function in the budding yeast Saccharomyces cerevisiae. Here we present the largest collection of defined yeast mutants ever generated within a single genetic background--a collection of over 11,000 strains, each carrying a transposon inserted within a region of the genome expressed during vegetative growth and/or sporulation. These insertions affect nearly 2,000 annotated genes, representing about one-third of the 6,200 predicted genes in the yeast genome. We have used this collection to determine disruption phenotypes for nearly 8,000 strains using 20 different growth conditions; the resulting data sets were clustered to identify groups of functionally related genes. We have also identified over 300 previously non-annotated open reading frames and analysed by indirect immunofluorescence over 1,300 transposon-tagged proteins. In total, our study encompasses over 260,000 data points, constituting the largest functional analysis of the yeast genome ever undertaken.     

Effect of various factors on the activity of trehalase from the larvae of Sesamia inferens Walker (Insect).

Trehalase from the salivary glands and the midgut of Sesamia inferens showed optimum activity at pH 5.8, and at temperatures of 50 and 60 degrees C respectively. The increase in the incubation period, enzyme concentration, and substrate concentration respectively increased the end-product, the hydrolysis, and the rate of hydrolysis of the substrate. Dialysis did not affect, tryptophan accelerated, and other amino acids and end-product inhibited the enzyme activity.     

Structure and synthesis of canine gastrin

Zusammenfassung Zwei Gastrine aus der Magenschleimhaut des Hundes wurden als Heptadecapeptide erkannt, und es wird die Synthese des einen beschrieben.     

A recent disruption of the main-belt asteroid P/2010 A2

Most inner main-belt asteroids are primitive rock and metal bodies in orbit about the Sun between Mars and Jupiter. Disruption, through high-velocity collisions or rotational spin-up, is believed to be the primary mechanism for the production and destruction of small asteroids and a contributor to dust in the Sun's zodiacal cloud, while analogous collisions around other stars feed dust to their debris disks. Unfortunately, direct evidence about the mechanism or rate of disruption is lacking, owing to the rarity of the events. Here we report observations of P/2010?A2, a previously unknown inner-belt asteroid with a peculiar, comet-like morphology. The data reveal a nucleus of diameter approximately 120?metres with an associated tail of millimetre-sized dust particles. We conclude that it is most probably the remnant of a recent asteroidal disruption in February/March 2009, evolving slowly under the action of solar radiation pressure, in agreement with independent work.     

Pharmacogenetics and ecogenetics

Concluding comments The study of pharmacogenetics and ecogenetics among different individuals and populations offers an unique opportunity to understand multiple, simultaneously occurring interactions between genes and the environment, and the subsequent phenotypic expression of heritable characters. Incorporation of appropiate ecogenetic diagnostic services into the general genetic services may be useful for public health monitoring in the prevention of occupational disease.The modern methods of molecular biochemistry will allow the characterization of hereditary traits affecting drug metabolism at the DNA level. Gene identification, isolation and cloning will help to determine whether gene duplication and other such events have taken place leading to species differences in the metabolism of drugs and xenobiotics.