Histone Methylation by NUE, a Novel Nuclear Effector of the Intracellular Pathogen Chlamydia trachomatis

Sequence analysis of the genome of the strict intracellular pathogen Chlamydia trachomatis revealed the presence of a SET domain containing protein, proteins that primarily function as histone methyltransferases. In these studies, we demonstrated secretion of this protein via a type III secretion mechanism. During infection, the protein is translocated to the host cell nucleus and associates with chromatin. We therefore named the protein nuclear effector (NUE). Expression of NUE in mammalian cells by transfection reconstituted nuclear targeting and chromatin association. In vitro methylation assays confirmed NUE is a histone methyltransferase that targets histones H2B, H3 and H4 and itself (automethylation). Mutants deficient in automethylation demonstrated diminished activity towards histones suggesting automethylation functions to enhance enzymatic activity. Thus, NUE is secreted by Chlamydia, translocates to the host cell nucleus and has enzymatic activity towards eukaryotic substrates. This work is the first description of a bacterial effector that directly targets mammalian histones

Enhanced x-ray emission coinciding with giant radio pulses from the Crab Pulsar

Giant radio pulses (GRPs) are sporadic bursts emitted by some pulsars that last a few microseconds and are hundreds to thousands of times brighter than regular pulses from these sources. The only GRP-associated emission outside of radio wavelengths is from the Crab Pulsar, where optical emission is enhanced by a few percentage points during GRPs. We observed the Crab Pulsar simultaneously at x-ray and radio wavelengths, finding enhancement of the x-ray emission by 3.8 ± 0.7% (a 5.4s detection) coinciding with GRPs. This implies that the total emitted energy from GRPs is tens to hundreds of times higher than previously known. We discuss the implications for the pulsar emission mechanism and extragalactic fast radio bursts.</p

Demography, Immigration Background, Difficulties with Living in Japan, and Psychological Distress Among Japanese Brazilians in Japan

This study examined the relationship of demography, immigration background, and concerns and difficulties associated with living in Japan to nonpsychotic psychological disturbance (i.e., “caseness”) measured by the GHQ-12. Data are from a sample of 265 Japanese Brazilians (JB) residing outside the Tokyo Metropolitan area. Employing multiple logistic regression analyses, it was found that JB who experienced lower economic conditions, lived alone, stayed relatively longer in Japan, migrated to Japan due to their dissatisfaction with the socio-economic conditions in Brazil, and who experienced severe family life concerns had a significantly higher ratio of “caseness,” that is psychologically distressed. In contrast, JB over the age of 25 years, who acquired moderate Japanese language proficiency and decided to return to Brazil as soon as possible, were observed to have a significantly lower ratio of psychological distress. Socio-cultural and situational interpretations of the findings are presented