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PubMed2025

Short-term diet intervention comprising of olive oil, vitamin D, and omega-3 fatty acids alters the small non-coding RNA (sncRNA) landscape of human sperm.

Offspring health outcomes are often linked with epigenetic alterations triggered by maternal nutrition and intrauterine environment. Strong experimental data also link paternal preconception nutrition with pathophysiology in the offspring, but the mechanism(s) routing effects of paternal exposures remain elusive. Animal experimental models have highlighted small non-coding RNAs (sncRNAs) as potential regulators of paternal effects. Here, we characterised the baseline sncRNA landscape of human sperm and the effect of a 6-week dietary intervention on their expression profile. This study involves sncRNAseq profiling, that was performed on a subset (n = 17) of the participants enrolled in the PREPARE trial: 9 from the control group and 8 from the intervention group. 5'tRFs, miRNAs and piRNAs were the most abundant sncRNA subtypes identified; their expression was associated with age, BMI, and sperm quality. Nutritional intervention with olive oil, vitamin D and omega-3 fatty acids altered expression of 3 tRFs, 15 miRNAs and 112 piRNAs, targeting genes involved in fatty acid metabolism and transposable elements in the sperm genome. PREPARE Trial registration number: ISRCTN50956936, Trial registration date: 10/02/2014.

Humans↗

PubMed2006

A novel class of small RNAs bind to MILI protein in mouse testes.

Small RNAs bound to Argonaute proteins recognize partially or fully complementary nucleic acid targets in diverse gene-silencing processes. A subgroup of the Argonaute proteins--known as the 'Piwi family'--is required for germ- and stem-cell development in invertebrates, and two Piwi members--MILI and MIWI--are essential for spermatogenesis in mouse. Here we describe a new class of small RNAs that bind to MILI in mouse male germ cells, where they accumulate at the onset of meiosis. The sequences of the over 1,000 identified unique molecules share a strong preference for a 5' uridine, but otherwise cannot be readily classified into sequence families. Genomic mapping of these small RNAs reveals a limited number of clusters, suggesting that these RNAs are processed from long primary transcripts. The small RNAs are 26-31 nucleotides (nt) in length--clearly distinct from the 21-23 nt of microRNAs (miRNAs) or short interfering RNAs (siRNAs)--and we refer to them as 'Piwi-interacting RNAs' or piRNAs. Orthologous human chromosomal regions also give rise to small RNAs with the characteristics of piRNAs, but the cloned sequences are distinct. The identification of this new class of small RNAs provides an important starting point to determine the molecular function of Piwi proteins in mammalian spermatogenesis.

Animals↗

PubMed2024

Conservation of antiviral systems across domains of life reveals immune genes in humans.

Deciphering the immune organization of eukaryotes is important for human health and for understanding ecosystems. The recent discovery of antiphage systems revealed that various eukaryotic immune proteins originate from prokaryotic antiphage systems. However, whether bacterial antiphage proteins can illuminate immune organization in eukaryotes remains unexplored. Here, we use a phylogeny-driven approach to uncover eukaryotic immune proteins by searching for homologs of bacterial antiphage systems. We demonstrate that proteins displaying sequence similarity with recently discovered antiphage systems are widespread in eukaryotes and maintain a role in human immunity. Two eukaryotic proteins of the anti-transposon piRNA pathway are evolutionarily linked to the antiphage system Mokosh. Additionally, human GTPases of immunity-associated proteins (GIMAPs) as well as two genes encoded in microsynteny, FHAD1 and CTRC, are respectively related to the Eleos and Lamassu prokaryotic systems and exhibit antiviral activity. Our work illustrates how comparative genomics of immune mechanisms can uncover defense genes in eukaryotes.

Humans↗

PubMed2026

Machine learning approaches for cancer prognosis and diagnosis via non-coding RNA: a comprehensive review.

Non-coding RNAs (ncRNAs), once considered genomic dark matter, are now established as key regulators of gene expression with widespread roles in cellular homeostasis and disease. In cancer, ncRNA expression is frequently and systematically dysregulated, and many of these molecules circulate in stable, protected form within biofluids, offering a compelling basis for non-invasive or minimally invasive diagnostic strategies. However, their clinical translation remains substantially hindered to date due to biological complexity, technical noise, and high dimensionality inherent to ncRNA expression datasets. In this context, machine learning (ML) has emerged as a powerful analytical tool to address these challenges, enabling the identification of subtle, reproducible ncRNA signatures predictive of diverse malignancies. This review critically evaluates ML-driven frameworks for cancer diagnosis and prognosis across four ncRNA subclasses, namely miRNAs, lncRNAs, circRNAs, and piRNAs, while also acknowledging the biophysical and thermodynamic models that reinforce ncRNA bioinformatics. Despite substantial methodological progress in ML-based cancer diagnosis and prognosis, key challenges persist, including tumor biological heterogeneity, limited multicenter validation, and the lack of widely adopted standardized protocols for preprocessing, normalization, and reporting workflows. Furthermore, many current ML models lack interpretability in biological or clinical context, constraining their translational utility. By synthesizing recent advances and identifying unresolved barriers, this review charts a roadmap for developing a robust, clinically actionable ncRNA biomarker platform for cancer detection. With global cancer incidence projected to exceed 35 million annual cases by 2050, validated ncRNA-ML-driven frameworks hold potential to revolutionize early-stage detection and personalized therapeutic strategies, thereby reducing the escalating socio-economic burden of cancer worldwide.

Humans↗

PubMed2026

Systematic identification of germ granule proteins reveals specialized roles in RNAi and small RNA inheritance.

Biomolecular condensates, such as germ granules, organize RNAi pathways critical for fertility and genome regulation. However, the protein composition and functional contributions of these condensates remain poorly defined. Here, we applied TurboID proximity labeling to the Caenorhabditis elegans germ granule protein SIMR-1, integrating mass spectrometry with genetic screening, CRISPR-based tagging, and small RNA sequencing. This systematic approach identified several previously uncharacterized germ granule proteins that contribute to fertility, germline immortality, exogenous RNAi, and transgenerational inheritance. Small RNA sequencing of 21 mutants revealed broad and class-specific defects in siRNA and miRNA biogenesis, with distinct factors associated with defects in WAGO-class 22G-RNAs, CSR-class 22G-RNAs, or histone-directed small RNAs. Among these, we identified PINT-1, a highly disordered protein that directly interacts with and is recruited to germ granules by the PIWI Argonaute PRG-1. PINT-1 is required for piRNA-dependent and -independent secondary siRNA biogenesis and germline development. Comparative genomics revealed that PINT-1 has coevolved with PRG-1 across clade V nematodes, with a conserved structured N terminus and a rapidly diverging repeat-rich intrinsically disordered region. Together, our findings expand the germ granule proteome and reveal how distinct condensate components contribute to specialized functions within the small RNA pathways, while highlighting an evolutionarily coadapted PIWI interactor critical for siRNA biogenesis.

Animals↗

PubMed2006

A PCR-based method for detection and quantification of small RNAs.

Recent cloning efforts have identified hundreds of thousands of small RNAs including micro RNAs (miRNAs), Piwi-interacting RNAs (piRNAs), and small nucleolar RNAs (snoRNAs). These non-coding small RNAs need to be further validated and characterized by detecting and quantifying their expression in different tissues and during different developmental courses. A simple, accurate, and sensitive method for small RNA expression profiling is in high demand. Here, we report such a PCR-based method.

Animals↗

PubMed2026

The Adaptive Roles of Active Transposable Elements in Insect Hosts.

Active transposable elements (TEs) are capable of generating new insertions in genomes and have historically been viewed as genomic parasites due to their largely detrimental or neutral effects. However, emerging evidence suggests that these elements also play a crucial role in driving adaptive evolution in insects. This mini-review synthesizes recent findings on how active TEs contribute to insect adaptation through various mechanisms, including regulation of gene expression, structural variation, and epigenetic effects. Notable examples of adaptation driven by active TEs include their roles in insecticide resistance, morphological adaptations, tolerance to harsh climates, and antiviral immune responses. We argue that while host silencing mechanisms, such as the piRNA pathway, tightly regulate TE activity to minimize harmful effects, the context-dependent activation of active TEs can generate beneficial genetic variation that enhances insect adaptations to anthropogenic and climatic pressures. Future research that integrates long-read sequencing, single-cell omics, and gene editing techniques will provide a robust mechanistic foundation for understanding the adaptive significance of active TEs in insects, with important implications for pest management, pollinator protection, and evolutionary biology.

Journal Article↗

PubMed2006

Argonaute: A scaffold for the function of short regulatory RNAs.

Argonaute is the central protein component of RNA-silencing mechanisms. It provides the platform for target-mRNA recognition by short regulatory guide RNA strands and the Slicer catalytic activity for mRNA cleavage in RNA interference. Multiple Argonaute sub-families can be identified phylogenetically yet, despite this diversity, molecular and sequence analyses show that Argonaute proteins share common molecular properties and the capacity to function through a common mechanism. Recently, the members of the Piwi sub-family have been shown to interact with new classes of short regulatory RNAs, Piwi-interacting RNAs (piRNAs) and repeat-associated small interfering RNAs (rasiRNAs), which has implications for developmental processes and introduces a new dimension to the field of RNA silencing.

Binding Sites↗

PubMed2026

A muskrat tissue atlas of small non-coding RNAs and their regulatory roles in muskrat musk secretion.

Muskrat musk, secreted by the male muskrat scent gland during the secretion period, is a valuable natural product with promising pharmacological activities. Its synthesis is regulated not only by coding genes but also by small non-coding RNAs (sncRNAs). However, a comprehensive tissue atlas of sncRNAs in muskrats has been lacking. To address this issue, we systematically profiled the expression levels of 6 sncRNA categories (piRNA [PIWI-interacting RNA], miRNA [microRNA], snoRNA [small nucleolar RNA], snRNA [small nuclear RNA], tRNA [transfer RNA], and other RNAs) across 13 tissues of the muskrat via deep sequencing. We identified 23,957 sncRNAs (∼ 65%) exhibiting tissue-specific expression patterns throughout the body. The results show that miRNA is the main contributor to tissue specificity. Eleven tissues showed a significantly higher number of miRNA-5p arm expressions compared to the 3p arm, although the brain was an exception. Quantitative results imply that miR-477-3p/5p and miR-794-3p are potentially involved in the regulation of muskrat musk synthesis and secretion in the muskrat scent glands. Their target genes were enriched in pathways related to energy supply, lipid metabolism, and cyclic morphological changes of the scent gland. Furthermore, we constructed a set of co-expressed miRNAs based on the hormone-dominated "brain-testis-scent gland" axis and the energy metabolism-dominated "brain-liver-scent gland" axis. These results provide the most comprehensive description to date of tissue-specific and ubiquitous sncRNAs in individual muskrat tissues. We anticipate that these data will enhance the understanding of the molecular regulation underlying muskrat musk synthesis and secretion.

Animals↗

PubMed2026

The complete sequence of the silkworm W chromosome uncovers its rapid evolution by large-scale duplications/deletions and translocation of W-linked genes.

The complete sequence of the W chromosome, which carries feminization activity in the silkworm, is crucial for understanding the sex-determination system in Lepidoptera. However, extensive accumulation of transposons due to lack of recombination, the very rare protein-coding genes and almost no information about molecular markers has hindered full W sequencing. We report the first complete silkworm W sequence (T2T_W, 11683305 bp) obtained by combining sequencing-assembly technologies and newly developed error detection methods, evaluated with genetically mapped W-RAPD markers, W-mutants, and W-derived BAC clones. The T2T_W sequence showed that the W is composed of a massive 92% accumulation of transposons and repeat sequences, among which the main constituents are intact LTR/LINE retrotransposons indicating recent expansions. In addition to Fem clusters producing Fem piRNA (Feminizer-derived PIWI-interacting RNA), we found 26 protein-coding genes in the W sequence. These include four gene pairs encoding zinc-finger motifs designated z1:z20 and a gene encoding serine/arginine repetitive matrix protein 1-like (SRRM1-like). To identify candidate genes for female sex-determination and differentiation we also sequenced the shortest W (3.8 Mb) from a translocation mutant with feminizing activity, which harbored four conventional genes: a Fem cluster, a pair of z1:z20 isoforms, z20-S, and a SRRM1-like gene. Phylogenetic analysis revealed that z1:z20 originated from a copy of an autosomal zinc-finger gene pair, z2:z21, translocated onto the W around 2.43 Mya and subsequently amplified to yield 4 W-linked zinc-finger gene pairs. The complete W sequence revealed that large-scale deletions and amplifications played a significant role in W chromosome evolution.

Animals↗

PubMed2025

Heterochromatin-based silencing of a foreign tandem repeat in Drosophila melanogaster shows unusual biochemistry and temperature sensitivity.

Eukaryotic genomes are packaged into chromatin, a regulatory nucleoprotein assembly. Establishment, maintenance, and interconversion of chromatin states is required for correct patterns of gene expression, genome integrity, and survival. Transcriptionally repressive heterochromatin minimizes mobilization of transposable elements and limits expansion of other repetitive DNA, but mechanisms for recognition of the latter sequences are not well established. We previously demonstrated in Drosophila melanogaster that transcripts derived from 1360 and Invader4 transposon insertions can trigger local conversion of transcriptionally permissive euchromatin to heterochromatin through the piRNA system, but only in a subset of genomic locations near existing blocks of heterochromatin. Here we show that a ~9 kb tandem array of the 36-nucleotide lac operator (lacO) sequence of Escherichia coli can form ectopic heterochromatin at a similar subset of sites, resulting in variegating expression of an adjacent reporter gene. Heterochromatin Protein 1a (HP1a) and histone deacetylation are required for lacO repeat-induced silencing, but, contrasting with previously described Position Effect Variegation (PEV), we do not observe increased histone H3 lysine 9 methylation. Silencing is effective at 25°C and suppressed at 18°C (in contrast to canonical PEV, which is enhanced at 18°C), indicating involvement of a temperature-sensitive component. Temperature switching experiments show that lacO repeat-induced heterochromatin formation is reversible throughout larval development following an HP1a-dependent initiation step in the early embryo. We conclude that the Drosophila nucleus can recognize a completely foreign tandem repeat as a target for heterochromatin formation, and that the heterochromatin structure established is distinct from that of endogenous tandem arrays.

HP1a↗

PubMed2006

A putative viral defence mechanism in archaeal cells.

Clusters of regularly spaced direct repeats, separated by unconserved spacer sequences, are ubiquitous in archaeal chromosomes and occur in some plasmids. Some clusters constitute around 1% of chromosomal DNA. Similarly structured clusters, generally smaller, also occur in some bacterial chromosomes. Although early studies implicated these clusters in segregation/partition functions, recent evidence suggests that the spacer sequences derive from extrachromosomal elements, and, primarily, viruses. This has led to the proposal that the clusters provide a defence against viral propagation in cells, and that both the mode of inhibition of viral propagation and the mechanism of adding spacer-repeat units to clusters, are dependent on RNAs transcribed from the clusters. Moreover, the putative inhibitory apparatus (piRNA-based) may be evolutionarily related to the interference RNA systems (siRNA and miRNA), which are common in eukarya. Here, we analyze all the current data on archaeal repeat clusters and provide some new insights into their diverse structures, transcriptional properties and mode of structural development. The results are consistent with larger cluster transcripts being processed at the centers of the repeat sequences and being further trimmed by exonucleases to yield a dominant, intracellular RNA species, which corresponds approximately to the size of a spacer. Furthermore, analysis of the extensive clusters of Sulfolobus solfataricus strains P1 and P2B provides support for the presence of a flanking sequence adjoining a cluster being a prerequisite for the incorporation of new spacer-repeat units, which occurs between the flanking sequence and the cluster. An archaeal database summarizing the data will be maintained at http://dac.molbio.ku.dk/dbs/SRSR/.

Archaea↗

PubMed2025

Tdrd15 is dispensable for male fertility and spermatogenesis in the golden hamster.

Tudor domain-containing proteins (TDRDs) constitute an evolutionarily conserved protein family and are critical for germline development and piRNA pathway regulation, with established roles in male fertility. While multiple TDRD family members have been functionally linked to spermatogenic impairment, the precise biological role of TDRD15 remains to be elucidated. We used CRISPR/Cas9-mediated gene editing to generate Tdrd15 knockout (KO) golden hamsters (Mesocricetus auratus), a model necessitated by the absence of a functional Tdrd15 ortholog in the mouse genome, to investigate its function in male reproduction. Phylogenetic analysis demonstrated that TDRD15 is strongly conserved among eutherian mammals, with testis-restricted expression patterns in hamsters. Despite the successful induction of frameshift mutations and significant transcriptional knockdown, Tdrd15 KO males maintained normal fertility parameters, including unaltered testicular architecture, spermatogenic progression (confirmed by periodic acidic-Schiff (PAS) staining and immunohistochemistry), and sperm quality metrics determined using a computer-assisted analysis. Quantitative polymerase chain reaction (qPCR) revealed compensatory overexpression of paralogous Tdrd genes in KO testes, implying functional redundancy within this protein family. This study provides the first experimental evidence that TDRD15 is dispensable for male fertility in golden hamsters under physiological conditions, thereby challenging the prevailing assumptions of its obligatory function in spermiogenesis. Altogether, these findings support a more targeted allocation of research efforts within the field of male reproductive biology.

Animals↗

PubMed2026

Non-coding RNAs in cancer: multi-omics insights, liquid biopsy advances, drug resistance mechanisms, and the road to clinical translation.

For most of the twentieth century, the transcriptional output of the human genome was thought to be biologically inert-a characterization that has been proven wrong in almost every important respect. Non-coding RNAs (ncRNAs) such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), small nucleolar RNAs (snoRNAs) and PIWI-interacting RNAs (piRNAs) are now thought of as vital regulators of gene expression in all the stages of cancer pathogenesis, including the initial epigenetic changes, metastatic spread and the development of therapeutic resistance. This review highlights four areas where the clinical potential of ncRNAs is most promising: reconstruction of ncRNA regulatory networks by multi-omics integration; circulating ncRNAs as minimally invasive cancer biomarkers; causal roles of ncRNAs in drug resistance through epithelial-mesenchymal plasticity, metabolic reprogramming, and stromal communication; and translation of ncRNA targeting strategies to clinical trials. We will need to invest equally in mechanistic rigor and translational infrastructure to move forward.

antisense oligonucleotides↗

PubMedDate not supplied

Influence of in vitro radiation on changes in nitric oxide in rat macrophages and smooth muscle cells.

We examined changes in nitric oxide (NO) levels resulting from irradiation of rat macrophage (RAM) and smooth muscle cells (SMC) in medium. Irradiation did not alter the NO concentration in the medium of either cell line. However, irradiation of 5 and 20 Gy enhanced the concentration of NO induced by lipopolysaccharide (LPS) in the medium containing RAM. Furthermore, 20 Gy of irradiation suppressed NO production induced by interferon-gamma in the RAM medium. Radiation seemed to enhance NO production more than that caused by Interleukin 1-beta only in the medium containing SMC. Next, mRNA levels of inducible NO synthase (NOS) were examined in RAM by Northern blotting following irradiation. Five Gy of irradiation did not generate iNOS mRNA expression, but did enhance iNOS piRNA expression induced by LPS, while 20 Gy suppressed the expression level of iNOS mRNA more than 5 Gy. This leads to the conclusion that radiation stimulation induced NO production through indirect action on the macrophage.

Animals↗

PubMed2006

Identification of microRNAs and other small RNAs from the adult newt eye.

PURPOSE: MicroRNAs (miRNAs) are capable of controlling gene expression by targeting complimentary sequences in many mRNAs. Thus, a small number of miRNAs are capable of regulating expression of many different genes. miRNAs have been found in all animals from Drosophila to human and they are highly conserved. This work was undertaken in order to identify such RNAs in the newt eye. METHODS: Cloning of these RNAs was attempted after isolating and fractionating total RNA from the adult newt eye. A gel slice ranging from about 15 to 30 nucleotides in length was cut and the extracted RNA was cloned after several processes involving reverse transcription and linker addition. For expression analysis and verification during the process of lens regeneration we used as a probe mir-124a. RESULTS: Several microRNAs, piRNAs and other small RNAS were identified. Some of them have eye specific gene targets in other species, but for many a function in the eye remains to be attributed. Expression of miR-124a showed an interesting regulation in the lens regeneration-competent dorsal iris. CONCLUSIONS: The cloned miRNAs and other small RNAs are the first to be reported for this animal and might bear significance in regulating processes that are unique to the newt eye, i.e., regeneration of the lens and retina.

Animals↗

PubMed1989

[Georg Ilberg (1862-1942). His life and medical-humanistic legacy].

Georg Ilberg, who is almost forgotten nowadays, was a scholar of Kraepelin and Ganser. From 1910 to 1928 he was director of the Landes-Heil- und Pflegeanstalt (country mental hospital) for mental patients Sonnenstein at Pirna. He was active in the scientific-literary field to a great age and worked as editor of the Allgemeine Zeitschrift für Psychiatrie from 1924 to 1934. Although he principally advocated the exclusion of certain mental patients from reproduction at the beginning of the 1930s, in a review in 1942, his integer humanist basic position and his pronounced social feeling made him to protest in public against the putting to death of mental in-patients.

Germany↗