A new CUT&RUN low volume-urea (LoV-U) protocol optimized for transcriptional co-factors uncovers Wnt/ß-catenin tissue-specific genomic targets.

Upon WNT/ß-catenin pathway activation, stabilized ß-catenin travels to the nucleus where it associates with the TCF/LEF transcription factors, constitutively bound to genomic Wnt-responsive elements (WREs), to activate target gene transcription. Discovering the binding profile of ß-catenin is therefore required to unambiguously assign direct targets of WNT signaling. Cleavage under targets and release using nuclease (CUT&RUN) has emerged as prime technique for mapping the binding profile of DNA-interacting proteins. Here, we present a modified version of CUT&RUN, named LoV-U (low volume and urea), that enables the robust and reproducible generation of ß-catenin binding profiles, uncovering direct WNT/ß-catenin target genes in human cells, as well as in cells isolated from developing mouse tissues. CUT&RUN-LoV-U outperforms original CUT&RUN when targeting co-factors that do not bind the DNA, can profile all classes of chromatin regulators and is well suited for simultaneous processing of several samples. We believe that the application of our protocol will allow the detection of the complex system of tissue-specific WNT/ß-catenin target genes, together with other non-DNA-binding transcriptional regulators that act downstream of ontogenetically fundamental signaling cascades.

Architecture of the chikungunya virus replication organelle.

Alphaviruses are mosquito-borne viruses that cause serious disease in humans and other mammals. Along with its mosquito vector, the Alphavirus chikungunya virus (CHIKV) has spread explosively in the last 20 years, and there is no approved treatment for chikungunya fever. On the plasma membrane of the infected cell, CHIKV generates dedicated organelles for viral RNA replication, so-called spherules. Whereas structures exist for several viral proteins that make up the spherule, the architecture of the full organelle is unknown. Here, we use cryo-electron tomography to image CHIKV spherules in their cellular context. This reveals that the viral protein nsP1 serves as a base for the assembly of a larger protein complex at the neck of the membrane bud. Biochemical assays show that the viral helicase-protease nsP2, while having no membrane affinity on its own, is recruited to membranes by nsP1. The tomograms further reveal that full-sized spherules contain a single copy of the viral genome in double-stranded form. Finally, we present a mathematical model that explains the membrane remodeling of the spherule in terms of the pressure exerted on the membrane by the polymerizing RNA, which provides a good agreement with the experimental data. The energy released by RNA polymerization is found to be sufficient to remodel the membrane to the characteristic spherule shape.

Adolescent attachment styles and their relation to the temperament and character traits of personality in a general population.

Attachment styles as well as personality traits in adolescents and adults have been found to be associated with their health outcomes and with their personality pathology. In this cross-sectional exploratory study, we study the relationship between attachment styles that derive from our data employing the items of Feeney et al. (1994) self-report attachment style questionnaire (ASQ), and personality traits given by the junior version of Cloninger et al. (1993) self-report temperament and character inventory (TCI), in a sample of 426 adolescents (54% females) from a general population. The secure attachment style was correlated significantly negatively with the personality trait harm avoidance (HA), but significantly positively with the personality traits novelty seeking (NS), reward dependence (RD), cooperativeness (CO) and self-transcendence (ST). The preoccupied (anxious/ambivalent) attachment style was correlated significantly positively with HA and NS, but significantly negatively with self-directedness (SD). The fearful-avoidant category was correlated significantly negatively with NS. Our five-factor solution of the attachment styles and their relation to the TCI point towards a need for a modification of the two-axis, four-category attachment model of Bartholomew (1990) and Bartholomew and Horowitz (1991), with their category dismissing-avoidant replaced by the two categories defined here as dismissing relations (correlated significantly negatively with CO) and dismissing others (correlated significantly negatively with RD and significantly positively with SD).

The Temperament Scale of Novelty Seeking in adolescents shows an association with season of birth opposite to that in adults.

We investigated the relationship between season of birth and the Junior Temperament and Character Inventory of Personality (Junior TCI, JTCI) in adolescents. The Temperament Scale of Novelty Seeking (NS) is significantly higher for females born during October-January as compared to females born otherwise. This association is opposite to that obtained earlier for adults. For both genders pooled, NS is significantly higher for those born during October-March compared to April-September. This association is also found when examining the data for those of age up to 18 years in a third independent study on the age range 11-81 years with the adult TCI. There is a greater tendency for exploration and risk-taking behavior as the child individuates from the family. Our study suggests that the effects of such environmental and developmental changes on personality are different in those born during October-March as compared to those born during April-September. The former show a higher rise in NS during adolescence and a steeper fall in NS during the years of adulthood, compared to the latter. Dopamine turnover is likely associated with NS, and the mutually inhibitory systems of dopamine and melatonin are the paracrine signals of day and night, respectively. Thus, the maternal entrainment of these systems during the prenatal period, or the postnatal environmental influence on these systems, may be different for those born during the short photoperiod of October-March as compared to those born during the long photoperiod part of the year.