Genetic effects of γ-radiation on natural populations ofDrosophila willistoni

Zusammenfassung Eine isolierte natürliche Population vonDrosophila willistoni erhielt während eines Jahres eine beträchtliche Beimischung von F₁-Co 60-bestrahlten Fliegen. Die genetische Analyse ergab, dass die Häufigkeit der letalen und semiletalen Allele nach 5 Generationen rasch wieder auf das Normale sank. Die Frequenz der Letalallele war allerdings noch hoch, gleich hoch wie in der in Massenkultur gehaltenen bestrahlten Zucht. Erst nach 15 Generationen sank sie zum Niveau der natürlichen Kontrollpopulation. Einzelne durch Bestrahlung erhaltene Letalallele blieben in der Population erhalten.

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Work developed (1957–1960) with grants in aid of the Conselho Nacional de Pesquisas (CNP_q: Brazilian Nat. Council of Research) and the Rockefeller Foundation.We acknowledge the constant interest and suggestions of Dr.A. R. Cordeiro in charge of the general planning of the radiation genetics project.     

Senataxin, the ortholog of a yeast RNA helicase, is mutant in ataxia-ocular apraxia 2

Ataxia-ocular apraxia 2 (AOA2) was recently identified as a new autosomal recessive ataxia. We have now identified causative mutations in 15 families, which allows us to clinically define this entity by onset between 10 and 22 years, cerebellar atrophy, axonal sensorimotor neuropathy, oculomotor apraxia and elevated alpha-fetoprotein (AFP). Ten of the fifteen mutations cause premature termination of a large DEAxQ-box helicase, the human ortholog of yeast Sen1p, involved in RNA maturation and termination.     

Some components of adaptive values of heterozygousDrosophila willistoni from irradiated natural populations

Zusammenfassung Die Analyse einiger Adaptationskomponenten (Häufigkeit des Schlüpfens aus dem Ei, Viabilität und Sterilität) bei einer isolierten natürlichen Population vonDrosophila willistoni, zeigte nach Bestrahlung mit Co 60 verminderte Adaptationswerte, während mehrerer Generationen nach Bestrahlung, mit progressiver Angleichung an das Kontrollniveau in den folgenden Generationen. Jedoch erreichte diese Population während 15 Generationen den Grad der Häufigkeit des Schlüpfens von unbehandelten Populationen nicht.     

Seven prostate cancer susceptibility loci identified by a multi-stage genome-wide association study

Prostate cancer (PrCa) is the most frequently diagnosed male cancer in developed countries. We conducted a multi-stage genome-wide association study for PrCa and previously reported the results of the first two stages, which identified 16 PrCa susceptibility loci. We report here the results of stage 3, in which we evaluated 1,536 SNPs in 4,574 individuals with prostate cancer (cases) and 4,164 controls. We followed up ten new association signals through genotyping in 51,311 samples in 30 studies from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium. In addition to replicating previously reported loci, we identified seven new prostate cancer susceptibility loci on chromosomes 2p11, 3q23, 3q26, 5p12, 6p21, 12q13 and Xq12 (P = 4.0 × 10(-8) to P = 2.7 × 10(-24)). We also identified a SNP in TERT more strongly associated with PrCa than that previously reported. More than 40 PrCa susceptibility loci, explaining ～25% of the familial risk in this disease, have now been identified.     

Multiple newly identified loci associated with prostate cancer susceptibility

Prostate cancer is the most common cancer affecting males in developed countries. It shows consistent evidence of familial aggregation, but the causes of this aggregation are mostly unknown. To identify common alleles associated with prostate cancer risk, we conducted a genome-wide association study (GWAS) using blood DNA samples from 1,854 individuals with clinically detected prostate cancer diagnosed at 相似文献   

Regulation of end-binding protein EB1 in the control of microtubule dynamics

The regulation of microtubule dynamics is critical to ensure essential cell functions, such as proper segregation of chromosomes during mitosis or cell polarity and migration. End-binding protein 1 (EB1) is a plus-end-tracking protein (+TIP) that accumulates at growing microtubule ends and plays a pivotal role in the regulation of microtubule dynamics. EB1 autonomously binds an extended tubulin-GTP/GDP-Pi structure at growing microtubule ends and acts as a molecular scaffold that recruits a large number of regulatory +TIPs through interaction with CAP-Gly or SxIP motifs. While extensive studies have focused on the structure of EB1-interacting site at microtubule ends and its role as a molecular platform, the mechanisms involved in the negative regulation of EB1 have only started to emerge and remain poorly understood. In this review, we summarize recent studies showing that EB1 association with MT ends is regulated by post-translational modifications and affected by microtubule-targeting agents. We also present recent findings that structural MAPs, that have no tip-tracking activity, physically interact with EB1 to prevent its accumulation at microtubule plus ends. These observations point out a novel concept of “endogenous EB1 antagonists” and emphasize the importance of finely regulating EB1 function at growing microtubule ends.     

Phosphorylation mechanisms in cloudy swelling

Riassunto Negli organi in rigonfiamento torbido sperimentale da tossina difterica l'attività esocinasica è immodificata, mentre è rallentata la formazione di P Ciò spiega perchè, negli animali intossicati con tossina difterica, il carico di glicoso determina ipofosfatemia meno netta. La diminuita formazione di P viene messa in rapporto con le alterazioni mitocondriali osservate nelle cellule in rigonfiamento torbido.