The single-cell chromatin accessibility landscape in mouse perinatal testis development.

Spermatogenesis depends on an orchestrated series of developing events in germ cells and full maturation of the somatic microenvironment. To date, the majority of efforts to study cellular heterogeneity in testis has been focused on single-cell gene expression rather than the chromatin landscape shaping gene expression. To advance our understanding of the regulatory programs underlying testicular cell types, we analyzed single-cell chromatin accessibility profiles in more than 25,000 cells from mouse developing testis.

scATAC-Seq reveals heterogeneity associated with spermatogonial differentiation in cultured male germline stem cells.

Spermatogonial stem cells are the most primitive spermatogonia in testis, which can self-renew to maintain the stem cell pool or differentiate to give rise to germ cells including haploid spermatids. All-trans-retinoic acid (RA), a bioactive metabolite of vitamin A, plays a fundamental role in initiating spermatogonial differentiation. In this study, single-cell ATAC-seq (scATAC-seq) was used to obtain genome-wide chromatin maps of cultured germline stem cells (GSCs) that were in control and RA-induced differentiation states.

Transcriptomic and epigenomic profiling of young and aged spermatogonial stem cells reveals molecular targets regulating differentiation.

Spermatogonial stem cells (SSC), the foundation of spermatogenesis and male fertility, possess lifelong self-renewal activity. Aging leads to the decline in stem cell function and increased risk of paternal age-related genetic diseases. In the present study, we performed a comparative genomic analysis of mouse SSC-enriched undifferentiated spermatogonia (Oct4-GFP+/KIT-) and differentiating progenitors (Oct4-GFP+/KIT+) isolated from young and aged testes.

MicroRNAs mediated targeting on the Yin-yang dynamics of DNA methylation in disease and development.

For decades, DNA methylation at the 5 position of cytosine (5mC) catalyzed by DNA methyltransferases (DNMTs) is a well-known epigenetic modification in mammalian genome, where it modulates chromatin remodeling and transcriptional silencing. The discovery of Ten-eleven translocation (TET) enzymes that oxidize 5mC to 5-hydroxymethylcytosine (5hmC) prompts a new era of DNA demethylation research. It is now established that in DNA demethylation pathway 5mC is first converted to 5-hydroxymethylcytosine (5hmC), then 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC) through TETs.

Identification of human papillomavirus type 58 lineages and the distribution worldwide.

Background: Human papillomavirus type 58 (HPV-58) accounts for a much higher proportion of cervical cancers in East Asia than other types. A classification system of HPV-58, which is essential for molecular epidemiological study, is lacking.

Methods And Results: This study analyzed the sequences of 401 isolates collected from 15 countries and cities.

Distribution of human papillomavirus type 58 variants in progression of cervical dysplasia in Korean women.

This cross-sectional study examined the distribution of HPV 58 sequence variation in Korean women for the first time. Among 1,750 Korean women, 53 women were positive for HPV 58 single infection, of whom 26 were without disease, 20 were with cervical intraepithelial neoplasia (CIN) 1, and 7 with CIN 2 or 3. Altogether, 36 different nucleotide sequence variations were identified with the L1, 20 within E2, 5 within E6, and 10 within E7.

Distribution of human papillomavirus types in anogenital warts of men.

Background: A wide spectrum of human papillomavirus (HPV) types can infect the male genitalia. An HPV vaccine covering HPV6 and 11 is now available. Detailed data on the distribution of these two types in anogenital warts is needed to assess the potential benefits of the vaccine.