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Lourdes Serrano Paloma Martínez-Redondo Anna Marazuela-Duque Berta N. Vazquez Scott J. Dooley Philipp Voigt David B. Beck Noriko Kane-Goldsmith Qiang Tong Rosa M. Rabanal Dolors Fondevila Purificación Mu?oz Marcus Krüger Jay A. Tischfield Alejandro Vaquero 《Genes & development》2013,27(6):639-653
The establishment of the epigenetic mark H4K20me1 (monomethylation of H4K20) by PR-Set7 during G2/M directly impacts S-phase progression and genome stability. However, the mechanisms involved in the regulation of this event are not well understood. Here we show that SirT2 regulates H4K20me1 deposition through the deacetylation of H4K16Ac (acetylation of H4K16) and determines the levels of H4K20me2/3 throughout the cell cycle. SirT2 binds and deacetylates PR-Set7 at K90, modulating its chromatin localization. Consistently, SirT2 depletion significantly reduces PR-Set7 chromatin levels, alters the size and number of PR-Set7 foci, and decreases the overall mitotic deposition of H4K20me1. Upon stress, the interaction between SirT2 and PR-Set7 increases along with the H4K20me1 levels, suggesting a novel mitotic checkpoint mechanism. SirT2 loss in mice induces significant defects associated with defective H4K20me1–3 levels. Accordingly, SirT2-deficient animals exhibit genomic instability and chromosomal aberrations and are prone to tumorigenesis. Our studies suggest that the dynamic cross-talk between the environment and the genome during mitosis determines the fate of the subsequent cell cycle. 相似文献
104.
A. Friães F. R. Pinto C. Silva-Costa M. Ramirez J. Melo-Cristino 《European journal of clinical microbiology & infectious diseases》2013,32(1):115-125
The profiling of the superantigen (SAg) encoding genes has been frequently used as a complementary typing method for group A streptococci (GAS), but a confusing gene nomenclature and a large diversity of primers used in screening has led to some conflicting results. The aim of this work was to develop a polymerase chain reaction (PCR) method capable of efficiently amplifying all the known allelic variants of these genes, and to evaluate the congruence of this methodology with other commonly used molecular typing methods. The presence of the 11 known SAg genes and two other exotoxin-encoding genes (speB and speF) was tested in a collection of 480 clinical GAS isolates, using two multiplex PCR reactions. The SAg gene profile was compared with other typing methods. Four naturally occurring deletions involving the genes speB, speF, and rgg were characterized, two of which were found among invasive isolates. The absence of the chromosomally encoded genes speG and smeZ was supported by Southern blot hybridization and associated with specific GAS lineages, while the presence of phage-encoded genes was more variable. Positive associations between SAg genes or between SAg profiles and emm types or pulsed-field gel electrophoresis (PFGE) clusters were observed. The results suggest that the SAg profile diversifies faster than other properties commonly used for molecular typing, such as emm type and multilocus sequence typing (MLST) sequence types (STs), and can be a useful complement in GAS molecular epidemiology. Still, the short-term stability of the SAg gene profile among prevalent genetic lineages may largely explain the observed associations between SAg genes. 相似文献
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Lourdes M G García Ana Paula T de Godoi Osvaldo A Serra Juliana F de Lima Leonardo de P A Almeida Tatiane C Dotta Silmara A M Corona Andra C dos Reis Alma B C E B Catirse 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》2020,32(1):51-56
107.
Maritza Del Carmen Quezada‐Conde Patricia de Lourdes Alvarez‐Velasco Edisson Fernando Lopez Marco Vinicio Medina Renata Pereira de Samuel Marques Marcia Turolla Wanderley E. Michel-Crosato Claudio Mendes Pannuti Antonio Carlos Frias Daniela Prcida Raggio Fausto Medeiros Mendes 《Dental traumatology》2020,36(5):510-517
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Kevin Chiem Brooke A. Fuentes David L. Lin Tung Tran Alexis Jackson Maria S. Ramirez Marcelo E. Tolmasky 《Antimicrobial agents and chemotherapy》2015,59(9):5851-5853
The in vitro activity of the aminoglycoside 6′-N-acetyltransferase type Ib [AAC(6′)-Ib] was inhibited by CuCl2 with a 50% inhibitory concentration (IC50) of 2.8 μM. The growth of an amikacin-resistant Klebsiella pneumoniae strain isolated from a neonate with meningitis was inhibited when amikacin was supplemented by the addition of Zn2+ or Cu2+ in complex with the ionophore pyrithione. Coordination complexes between cations and ionophores could be developed for their use, in combination with aminoglycosides, to treat resistant infections. 相似文献
109.
Testing the Initial Efficacy of a Mailed Screening and Brief Feedback Intervention to Reduce At‐Risk Drinking in Middle‐Aged and Older Adults: The Comorbidity Alcohol Risk Evaluation Study 下载免费PDF全文
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