The eukaryotic leading and lagging strand DNA polymerases are loaded onto primer-ends via separate mechanisms but have comparable processivity in the presence of PCNA

Saccharomyces cerevisiae DNA polymerase δ (Pol δ) and DNA polymerase ε (Pol ε) are replicative DNA polymerases at the replication fork. Both enzymes are stimulated by PCNA, although to different levels. To understand why and to explore the interaction with PCNA, we compared Pol δ and Pol ε in physical interactions with PCNA and nucleic acids (with or without RPA), and in functional assays measuring activity and processivity. Using surface plasmon resonance technique, we show that Pol ε has a high affinity for DNA, but a low affinity for PCNA. In contrast, Pol δ has a low affinity for DNA and a high affinity for PCNA. The true processivity of Pol δ and Pol ε was measured for the first time in the presence of RPA, PCNA and RFC on single-stranded DNA. Remarkably, in the presence of PCNA, the processivity of Pol δ and Pol ε on RPA-coated DNA is comparable. Finally, more PCNA molecules were found on the template after it was replicated by Pol ε when compared to Pol δ. We conclude that Pol ε and Pol δ exhibit comparable processivity, but are loaded on the primer-end via different mechanisms

« La Cinémathèque suisse a 25 ans ! » : l’exposition Images du cinéma comme espace de célébration et d’historicisation du cinéma helvétique

En 1973, la Cinémathèque suisse (CS) célèbre à la fois les trente ans de la fondation des Archives cinématographiques suisses, association bâloise qui la précède, et les vingt-cinq ans de son établissement à Lausanne. Pour l’occasion, elle organise dans la capitale vaudoise l’exposition Images du cinéma au Musée des arts décoratifs (MAD — situé à l’avenue Villamont ) du 27 octobre au 25 novembre, et programme une série de projections à l’aula du collège de Béthusy (Fig. 1) . Ces deux pans d’..

Isolation of low erucic acid-containing genotype of Indian mustard (Brassica juncea Czern. and Coss.) through F1 hybrid anther culture

Reciprocal crosses were done between two cultivars; cv. RJ15 and cv. RLM198 of Indian mustard (Brassica juncea). Anther derived lines designated as A1 plants, were raised through anther culture fromthese F1 hybrid plants. 45% germination was obtained from distinctly shriveled and small A1 seeds and grown along with the F2 plants in the same agro-climatic conditions. Subsequently the lines werecompared for inheritance pattern between the lines. A normal frequency distribution curve for siliqua per plant was obtained in all the lines reflecting a similar pattern of recombination. Few seeds from theplants of each lines exhibiting high number of siliqua per plant, were isolated for analysis of erucic acid. Three plants in which erucic acid content was lower than the parent cultivars of A2 generationwere identified. This showed that contrasting characters could be obtained from A2 plants where the traits are oligo or monogenic through anther culture

Egy sokoldalú muzsikus dokumentumai. Faragó György (1913–1944)

Tanulmány Faragó György zongoraművész hagyatékáról, annak feldolgozásáról, s a kutatás legújabb eredményeiről