Fostering a Sense of Belonging and Empowerment for Male Students in Undergraduate Teacher Education Courses

How supporting males on an undergraduate course can support their engagement

A-MYB/TCFL5 regulatory architecture ensures the production of pachytene piRNAs in placental mammals

In male mice, the transcription factor A-MYB initiates the transcription of pachytene piRNA genes during meiosis. Here, we report that A-MYB activates the transcription factor Tcfl5 produced in pachytene spermatocytes. Subsequently, A-MYB and TCFL5 reciprocally reinforce their own transcription to establish a positive feedback circuit that triggers pachytene piRNA production. TCFL5 regulates the expression of genes required for piRNA maturation and promotes transcription of evolutionarily young pachytene piRNA genes, whereas A-MYB activates the transcription of older pachytene piRNA genes. Intriguingly, pachytene piRNAs from TCFL5-dependent young loci initiate the production of piRNAs from A-MYB-dependent older loci, ensuring the self-propagation of pachytene piRNAs. A-MYB and TCFL5 act via a set of incoherent feedforward loops that drive regulation of gene expression by pachytene piRNAs during spermatogenesis. This regulatory architecture is conserved in rhesus macaque, suggesting that it was present in the last common ancestor of placental mammals

Diasporic virginities: social representations of virginity and identity formation amongst British arab muslim women

This study compares how practising and non-practising British Arab Muslim women position themselves in relation to representations of virginity. Overall, in our qualitative study, we found that representations of culture and religion influenced social practices and social beliefs in different ways: non-practising Muslim women felt bound by culture to remain virgins, while practising Muslim women saw it as a religious obligation but were still governed by culture regarding the consequences of engaging in premarital sex. Interestingly, some practising Muslim participants used Mut’a (a form of temporary ‘marriage’) to justify premarital sex. This, however, did not diminish the importance of virginity in their understanding and identification as Arab women. In fact, this study found that virginity, for the British Arabs interviewed, embodied a sense of ‘Arabness’ in British society. Positioning themselves as virgins went beyond simply honour; it was a significant cultural symbol that secured their sense of cultural identity. In fact this cultural identity was often so powerful that it overrode their Islamic identities, prescribing their behaviour even if religion was seen as more ‘forgiving’

A-MYB/TCFL5 regulatory architecture ensures the production of pachytene piRNAs in placental mammals

In male mice, the transcription factor A MYB initiates the transcription of pachytene piRNA genes during meiosis. Here, we report that A MYB activates the transcription factor Tcfl5 produced in pachytene spermatocytes. Subsequently, A MYB and TCFL5 reciprocally reinforce their own transcription to establish a positive feedback circuit that triggers pachytene piRNA production. TCFL5 regulates the expression of genes required for piRNA maturation and promotes transcription of evolutionarily young pachytene piRNA genes, whereas A-MYB activates the transcription of older pachytene piRNA genes. Intriguingly, pachytene piRNAs from TCFL5-dependent young loci initiates the production of piRNAs from A-MYB-dependent older loci ensuring the self-propagation of pachytene piRNAs. A MYB and TCFL5 act via a set of incoherent feedforward loops that drive regulation of gene expression by pachytene piRNAs during spermatogenesis. This regulatory architecture is conserved in rhesus macaque, suggesting that it was present in the last common ancestor of placental mammals

A Key Role of Dendritic Cells in Probiotic Functionality

BACKGROUND: Disruption of the intestinal homeostasis and tolerance towards the resident microbiota is a major mechanism involved in the development of inflammatory bowel disease. While some bacteria are inducers of disease, others, known as probiotics, are able to reduce inflammation. Because dendritic cells (DCs) play a central role in regulating immune responses and in inducing tolerance, we investigated their role in the anti-inflammatory potential of probiotic lactic acid bacteria. METHODOLOGY/PRINCIPAL FINDINGS: Selected LAB strains, while efficiently taken up by DCs in vitro, induced a partial maturation of the cells. Transfer of probiotic-treated DCs conferred protection against 2, 4, 6-trinitrobenzenesulfonic acid (TNBS)-induced colitis. Protection was associated with a reduction of inflammatory scores and colonic expression of pro-inflammatory genes, while a high local expression of the immunoregulatory enzyme indolamine 2, 3 dioxgenase (IDO) was observed. The preventive effect of probiotic-pulsed DCs required not only MyD88-, TLR2- and NOD2-dependent signaling but also the induction of CD4+ CD25+ regulatory cells in an IL-10-independent pathway. CONCLUSIONS/SIGNIFICANCE: Altogether, these results suggest that selected probiotics can stimulate DC regulatory functions by targeting specific pattern-recognition receptors and pathways. The results not only emphasize the role of DCs in probiotic immune interactions, but indicate a possible role in immune-intervention therapy for IBD

Spatio-Temporal Tracking and Phylodynamics of an Urban Dengue 3 Outbreak in São Paulo, Brazil

The dengue virus has a single-stranded positive-sense RNA genome of ∼10.700 nucleotides with a single open reading frame that encodes three structural (C, prM, and E) and seven nonstructural (NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5) proteins. It possesses four antigenically distinct serotypes (DENV 1–4). Many phylogenetic studies address particularities of the different serotypes using convenience samples that are not conducive to a spatio-temporal analysis in a single urban setting. We describe the pattern of spread of distinct lineages of DENV-3 circulating in São José do Rio Preto, Brazil, during 2006. Blood samples from patients presenting dengue-like symptoms were collected for DENV testing. We performed M-N-PCR using primers based on NS5 for virus detection and identification. The fragments were purified from PCR mixtures and sequenced. The positive dengue cases were geo-coded. To type the sequenced samples, 52 reference sequences were aligned. The dataset generated was used for iterative phylogenetic reconstruction with the maximum likelihood criterion. The best demographic model, the rate of growth, rate of evolutionary change, and Time to Most Recent Common Ancestor (TMRCA) were estimated. The basic reproductive rate during the epidemics was estimated. We obtained sequences from 82 patients among 174 blood samples. We were able to geo-code 46 sequences. The alignment generated a 399-nucleotide-long dataset with 134 taxa. The phylogenetic analysis indicated that all samples were of DENV-3 and related to strains circulating on the isle of Martinique in 2000–2001. Sixty DENV-3 from São José do Rio Preto formed a monophyletic group (lineage 1), closely related to the remaining 22 isolates (lineage 2). We assumed that these lineages appeared before 2006 in different occasions. By transforming the inferred exponential growth rates into the basic reproductive rate, we obtained values for lineage 1 of R0 = 1.53 and values for lineage 2 of R0 = 1.13. Under the exponential model, TMRCA of lineage 1 dated 1 year and lineage 2 dated 3.4 years before the last sampling. The possibility of inferring the spatio-temporal dynamics from genetic data has been generally little explored, and it may shed light on DENV circulation. The use of both geographic and temporally structured phylogenetic data provided a detailed view on the spread of at least two dengue viral strains in a populated urban area

The tiny, conserved zinc-finger protein GTSF1 helps PIWI proteins achieve their full catalytic potential [preprint]

Argonaute proteins use nucleic acid guides to find and bind specific DNA or RNA target sequences. Argonaute proteins can be found in all kingdoms of life, and play diverse biological functions including genome defense, gene regulation, and chromosome partitioning. Many Argonautes retain their ancestral endoribonuclease activity, cleaving the phosphodiester bond between target nucleotides t10 and t11. In animals, a specialized class of Argonautes, the PIWI proteins, use 21–35 nt PIWI-interacting RNAs (piRNAs) to direct transposon silencing, protect the germline genome, and regulate gene expression during gametogenesis1. The piRNA pathway is required for fertility in one or both sexes of nearly all animals. Both piRNA production and function require RNA cleavage catalyzed by PIWI proteins. Spermatogenesis in mice and other placental mammals requires three distinct, developmentally regulated PIWI proteins: MIWI (PIWIL1), MILI (PIWIL2), and MIWI2 (PIWIL4)24; the piRNA-guided endoribonuclease activities of MIWI and MILI are essential to produce functional sperm5,6. piRNA-directed silencing in mice, insects, and worms also requires Gametocyte-Specific Factor 1 (GTSF1), a PIWI-associated protein of unknown function712. Here, we report that GTSF1 potentiates the weak, intrinsic, piRNA-directed RNA cleavage activities of PIWI proteins, transforming them into efficient endoribonucleases. GTSF1 represents the first example of an auxiliary protein that potentiates the catalytic activity of an Argonaute protein