55 research outputs found
Ybp2 Associates with the Central Kinetochore of Saccharomyces cerevisiae and Mediates Proper Mitotic Progression
The spindle checkpoint ensures the accurate segregation of chromosomes by monitoring the status of kinetochore attachment to microtubules. Simultaneous mutations in one of several kinetochore and cohesion genes and a spindle checkpoint gene cause a synthetic-lethal or synthetic-sick phenotype. A synthetic genetic array (SGA) analysis using a mad2Δ query mutant strain of yeast identified YBP2, a gene whose product shares sequence similarity with the product of YBP1, which is required for H2O2-induced oxidation of the transcription factor Yap1. ybp2Δ was sensitive to benomyl and accumulated at the mitotic stage of the cell cycle. Ybp2 physically associates with proteins of the COMA complex (Ctf19, Okp1, Mcm21, and Ame1) and 3 components of the Ndc80 complex (Ndc80, Nuf2, and Spc25 but not Spc24) in the central kinetochore and with Cse4 (the centromeric histone and CENP-A homolog). Chromatin-immunoprecipitation analyses revealed that Ybp2 associates specifically with CEN DNA. Furthermore, ybp2Δ showed synthetic-sick interactions with mutants of the genes that encode the COMA complex components. Ybp2 seems to be part of a macromolecular kinetochore complex and appears to contribute to the proper associations among the central kinetochore subcomplexes and the kinetochore-specific nucleosome
Correction of Population Stratification in Large Multi-Ethnic Association Studies
The vast majority of genetic risk factors for complex diseases have, taken
individually, a small effect on the end phenotype. Population-based
association studies therefore need very large sample sizes to detect
significant differences between affected and non-affected individuals.
Including thousands of affected individuals in a study requires recruitment
in numerous centers, possibly from different geographic regions.
Unfortunately such a recruitment strategy is likely to complicate the study
design and to generate concerns regarding population stratification.We analyzed 9,751 individuals representing three main ethnic groups -
Europeans, Arabs and South Asians - that had been enrolled from 154 centers
involving 52 countries for a global case/control study of acute myocardial
infarction. All individuals were genotyped at 103 candidate genes using
1,536 SNPs selected with a tagging strategy that captures most of the
genetic diversity in different populations. We show that relying solely on
self-reported ethnicity is not sufficient to exclude population
stratification and we present additional methods to identify and correct for
stratification.Our results highlight the importance of carefully addressing population
stratification and of carefully “cleaning” the sample
prior to analyses to obtain stronger signals of association and to avoid
spurious results
Simultaneous analyses of N-linked and O-linked glycans of ovarian cancer cells using solid-phase chemoenzymatic method
Apoptosis in Relation to Androgen Independence in Experimental and Clinical Prostate Cancer
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