Gene

This study aims to quantify the genetic similarity of different species (from fish to humans) to the human reference genome (pp6, Homo sapiens.GRCh38) based on the allele presence/absence patterns of 33 language/cognition related gene SNV loci, identify key breakpoints during evolution, and evaluate the enrichment of language and cognition genes at these breakpoints. We designed a similarity calculation method relying on binary features (four columns for A/T/C/G), adopted five difference/distance measures (Sorensen, Rogers, Nei, Reynolds, and Hellinger), and converted them into similarity values (1/(1+distance)). For each method, samples were independently ranked, the first derivative of similarity was computed, and the top 12 peaks were selected as candidate breakpoints. Results show that the similarity curves from the five methods are highly consistent (correlation coefficients >0.9), with major peaks concentrated at positions 355, 363, 381, 382, 390, 400, etc., where the corresponding samples are predominantly ancient hominins and primates. Furthermore, we defined 13 peak groups (starting positions 355-401). For each peak within a group, pairwise SNV differences between the peak apex sample and its immediate left neighbor were compared, and the intersection F_INTERSECTION (shared differential loci) was obtained. For each F_INTERSECTION, we calculated the proportions of language genes and cognition genes. In addition, we computed the differential sets between adjacent groups' F_INTERSECTION to trace the gradual emergence of new loci. In F_INTERSECTION, language genes accounted for an average of 59.5%, and cognition genes for an average of 62.9%. The proportion of language genes reached a peak at position 383 (61.2%), while cognition genes peaked at position 386 (64.9%). High frequency peak samples include c25, c27, and ja2, suggesting that language cognition genes may have undergone independent intensification during Eurasian evolution. Differential analysis between adjacent F_INTERSECTION revealed a stepwise acquisition of new loci from position 355 to 401, with three bursts of newly added loci along the entire evolutionary axis. This study provides a quantitative framework based on similarity curves, offers a novel molecular perspective for understanding the evolution of language and cognitive abilities, and highlights the potential importance of East Asian archaic hominins in the evolution of language cognition genes.

BackgroundHeterochromatic long arm of mouse Y chromosome harbors the multicopy species-specific sequences Ssty, Sly, Asty and Orly that are transcribed in testis and have known functions in male fertility. Of these Ssty and Sly encode proteins - yet all the transcripts are not translated. To investigate the roles of these Y-heterochromatic transcripts further, we analyzed them. MethodsMice with 2/3rd deletion of the Y-chromosome (XYRIIIqdel) and its wild type (XYRIII) were used in this study. Bioinformatic approaches, small RNA northern blots, Electrophoretic Mobility Shift Assays, Luciferase reporter assays, dPCR analysis, RT-qPCR assays and western blotting techniques were used to identify piRNAs that regulate autosomal genes. ResultsWe demonstrate that the multicopy gene families from mouse Y-long arm generate piRNAs predominantly in testis. We observed sequences homologous to these piRNAs in the UTRs of a few autosomal genes, which are differentially expressed in the sperms of XYRIIIqdel mice. Furthermore, the Endogenous Retrovirus Element (ERV) LTR, found in the Orly1 transcript identified piRNAs in the database, showed homology to UTRs and associated genomic regions of a few autosomal genes. Orly1 showed a reduction in genomic copy number by digital PCR in XYRIIIqdel mice. One of the four autosomal genes containing the ERV segment in their UTRs, showed a differential testicular protein expression in the mutant mice. ConclusionsThus, we further elucidate that different classes of repeats from Y-chromosome regulate autosomal gene expression via piRNAs. Besides, this study also identified novel roles for a Y-derived ERV in autosomal gene regulation in testis.

The natural vector method is an important method for the analysis of biological sequences. In this study, we applied this method to population genetic analysis, with the core purpose of using it to evaluate the characteristics of a set of sequences rather than just pairwise comparison. We used the mitochondrial genome dataset from the human 1000 Genomes Project as a dataset to verify the feasibility of this improved natural vector method. The results showed that the modified natural vector method could be used for various population genetic approaches at least in the sense of population average, including the calculation of principal component analysis, population structure analysis and genetic diversity parameters. The results were in good agreement with those based on traditional molecular genetic markers such as SNP. The new method validates the feasibility of natural vector method for population genetic analysis and provides a framework for the application of matchless pair method to population genomic analysis on a wider scale.

BackgroundMultiple epidemiological studies have given a global perspective that hypertension leads to changes in telomere length (TL). This study aimed to investigate the association between leukocyte telomere length and lifestyle factors among individuals with hypertension, a family history of the disease and healthy controls. MethodsThis pilot exploratory cross-sectional study included 45 participants (n = 15 per group) divided into hypertensive, familial hypertensive, and control groups. Lifestyle behaviors were assessed using the FANTASTIC Lifestyle Checklist, evaluating domains such as physical activity, diet, sleep, and stress. Relative telomere length (T/S ratio) of leucocytes was measured from peripheral blood samples using quantitative real-time PCR (qPCR). Data were analyzed using SPSS software, with ANOVA, Kruskal-Wallis test, and multivariable linear regression applied for statistical analysis. ResultsRelative telomere length differed significantly among the study groups (p = 0.008), with hypertensive participants demonstrating the highest median telomere-to-single-copy gene (T/S) ratio (2.66), followed by familial hypertensive (1.25) and control participants (0.87). Total lifestyle scores also varied significantly across groups (p < 0.001), with hypertensive individuals exhibiting higher mean scores (77.07 {+/-} 5.59) than familial hypertensive (67.20 {+/-} 3.00) and control participants (67.07 {+/-} 5.97). A modest positive correlation was observed between total lifestyle score and relative telomere length (r = 0.329, p < 0.05), suggesting that healthier lifestyle behaviors in diagnosed hypertensive subjects following healthy lifestyles and regular medications were associated with longer telomeres. However, in multivariable linear regression analyses, lifestyle score, age, gender, hypertension status, and family history of hypertension were not independently associated with telomere length (all p > 0.05). ConclusionLifestyle scores were positively associated with telomeres, and significantly higher telomere ratios in hypertensive subjects suggest complex biological interactions that require further investigation through larger longitudinal studies in the target population.

Seasonal breeding is a remarkable adaptive trait, but it constrains efficient production in the sheep industry. Recent studies have shown that seasonal breeding is associated with endogenous circannual rhythms, which are regulated in part by the circadian clock system. FBXL3, a pivotal component of the SCF (SKP1 - CUL1 - F-box) E3 ubiquitin ligase complex, is a known determinant of the mammalian circadian period. In this study, we identified a missense mutation, T183M, in FBXL3 through selective sweep analysis. The allele frequency of this mutation differed significantly between sheep breeds exhibiting year-round estrus and those showing seasonal breeding patterns. The association between the T183M mutation and seasonal breeding was further validated using an ovariectomized, estradiol-implanted sheep model. We then generated mice carrying the homologous T183M mutation and found that they exhibited significantly lengthened circadian periods, accompanied by reduced CRY1 expression and increased CLOCK expression. Co-immunoprecipitation assays confirmed that the mutation reduced the interaction between FBXL3 and CRY1. These findings demonstrate an evolutionarily conserved role of FBXL3 in the circadian clock system. We propose that the T183M mutation disrupts day-length recognition, thereby influencing seasonal estrus in sheep. Author summarySeasonal breeding limits sheep productivity and is regulated by circadian rhythms, yet the key genetic determinants remain poorly understood. Here, we identified an FBXL3 T183M missense mutation whose allele frequency differed markedly between year-round-estrous and seasonally breeding sheep, and validated its association with seasonal reproduction in a sheep population. Functional analyses in mutant mice showed that this variant lengthened the circadian period, disrupted the expression of core clock genes, and weakened the interaction between FBXL3 and CRY1. These findings suggest that the FBXL3 T183M variant impairs day-length perception, thereby modulating seasonal estrus in sheep. Our study reveals a conserved circadian mechanism underlying seasonal breeding and highlights FBXL3 T183M as a promising genetic target for improving reproductive performance in sheep.

Epigenetics regulate cell-cycle kinetics, differentiation, apoptosis, and migration. Nuclear receptor-binding SET Domain (NSD) histone methyltransferases represent a family of oncoproteins with aberrant expression in cancer. Emerging reports suggest that NSD1 could be an attractive target as its expression is correlated with poor prognosis and tumorigenesis. Previously, we reported the target validation and structure-based virtual screening against NSD1, leading to the selection of several hit molecules with relatively high docking and MMGBSA delta G Bind scores. One of the best-fit molecules identified was 5-O-sulfamoyl adenosine (5-SA) and was compared with the S-Adenosyl-l-Cysteine (SAC), a structural analog of S-Adenosyl-l-Methionine (SAM) for its inhibitory activity against NSD1. IC50 values for 5-SA and SAC against NSD1 were 53.819 {micro}M and 115.003 {micro}M respectively. 5-SA significantly reduced the viability of DU145 and HepG2 cells with IC50 values calculated as 198{micro}M and 168.3 {micro}M respectively. It also reduced the RNA and protein expression levels of NSD1 and subsequently prevented dimethylation of lysine 36 on histone H3 (H3K36me2). Furthermore, 5-SA impeded proliferation, and migration, altered the cell cycle phase, and induced cell apoptosis. Interestingly, 5-SA potentiated the anticancer activity of 5-Fluorouracil (5-FU) against cancer cells. The xenograft model of prostate cancer also showed that 5-SA significantly reduced the tumor growth kinetics. However, the combination of 5-SA and 5-FU synergistically reduced tumor growth and improved survival of animals. To the best of our knowledge, we report for the first time that 5-SA mediated inhibition of NSD1 enhanced the tumor sensitivity to 5-FU and thereby, improved the tumor growth and progression. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=160 SRC="FIGDIR/small/731397v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@e2f0bdorg.highwire.dtl.DTLVardef@12b2ca6org.highwire.dtl.DTLVardef@1807613org.highwire.dtl.DTLVardef@c7f8f0_HPS_FORMAT_FIGEXP M_FIG C_FIG

RationaleOxidative stress, resulting from an imbalance between the production of reactive oxygen species (ROS) and antioxidant defence mechanisms, disrupts cellular redox homeostasis and contributes to damage of biomolecules, including nucleic acids, proteins and lipids. Such disturbances can impair intracellular signalling pathways and have been implicated in the pathophysiology of female reproductive disorders. Nitroblue Tetrazolium (NBT) is a distinctive dye that assesses cellular redox activity in neutrophils through the detection of superoxide anion (O2-). However, the relationship between neutrophil-derived oxidative stress and women infertility remains to be fully elucidated. Aim of the study: We aimed to investigate the role of neutrophil oxidative stress in women infertility using a novel Nitroblue Tetrazolium (NBT) method developed in our laboratory. Materials and methodsBlood and serum specimens were obtained from a total of 100 Libyan women, comprising healthy fertile women (n = 21; controls) and infertile women (n = 79). Superoxide anion (O2-) generation in neutrophils was assessed using the novel NBT method, while malondialdehyde (MDA), a marker of lipid peroxidation, was determined using the thiobarbituric acid reactive substances (TBARS) assay. ResultsA significant increase in both NBT-reactivity levels and the percentage of NBT-positive neutrophils was observed in infertile women compared with healthy fertile controls (P < 0.0001). In addition, MDA levels were significantly higher in infertile women than in the control group, indicating enhanced lipid peroxidation. MDA levels were positively correlated with NBT-reactivity levels (r = 0.410, P = 0.0001) and the percentage of NBT-positive neutrophils (r = 0.21, P = 0.047). A significant positive correlation was also observed between NBT-reactivity levels and the percentage of NBT-positive neutrophils (r = 0.510, P = 0.0001), demonstrating a close association between neutrophil oxidative activity and lipid peroxidation in women infertility. ConclusionThe present study demonstrates the utility of a novel NBT method for detecting reactive oxygen species (ROS), a marker of oxidative stress, in neutrophils from both blood and serum specimens. The findings demonstrate increased neutrophil-derived oxidative stress in infertile women and suggest that this method may have potential as a diagnostic tool for the assessment of women infertility. ImpactThis study provides evidence that neutrophil-derived oxidative stress is significantly increased in women infertility and demonstrates the application of a novel Nitroblue Tetrazolium (NBT) assay for assessing oxidative stress in both blood and serum specimens. The significant associations between NBT-reactivity, NBT-positive neutrophils and malondialdehyde levels provide further insight into the contribution of oxidative stress to female reproductive pathophysiology. These findings support the potential utility of the novel NBT method as a simple and reliable diagnostic approach for evaluating oxidative stress in women infertility and provide a foundation for future studies investigating oxidative stress biomarkers in reproductive medicine.

Background: Pulmonary arterial hypertension (PAH) is a serious disease with poor prognosis, especially in infants or preterm babies and there is still no optimal treatment for this disease. Noradrenalin (NE) is a vasoactive mediator which is released by sympathetic ganglion. According to previous studies, NE/1-adrenoreceptors is not only in regulating normal physiologic responses, but also in the pathogenesis of PAH. However, the mechanisms of NE in PAH are not fully understood. Methods: Human PASMC (PASMC) was used in this study. Cell viability assay and Wound healing assay were used to evaluate the proliferation and migration of PASMC. Immunoprecipitation and western blots analysis were used to investigate the mechanisms which involved in NE-induced PASMC proliferation. Results: We investigated that NE could induce human PASMC proliferation and migration. Furthermore, we first find that endothelin 1 (ET-1) signaling pathway plays an important role in NE-induced PASMC proliferation. ET1 is a critical molecular which is known for regulating cell growth and migration. We investigated that NE could increase NE-1 secretion, further enhancing ET-1 bind to its receptors. For further clarifying the downstream signals in NE/ET-1 induced PASMC proliferation, we detected the phosphorylation and expression levels of ERK and JNK. Conclusions: By combining the results from ours and previous studies, we believed that JNK/c-jun pathway may play an important role in NE-induced PASMC proliferation. Key Words: Noradrenaline; Pulmonary Arterial Hypertension; Pulmonary Artery Smooth Muscle Cells; Endothelin-1; JNK/c-Jun Signaling.

Anoxia is a major stress for most vertebrates and frequently accompanies harsh winter conditions, particularly in species that spend much of the season frozen solid. North American freeze-tolerant wood frogs (Rana sylvatica) can survive several months without oxygen and endure whole-body freezing for up to eight months of the year, with [~]70% of total body water frozen as extracellular ice, yet revive when temperatures rise in spring. Survival depends on multiple adaptations, including tolerance of prolonged oxygen deprivation while frozen, when breathing and circulation are halted. A key strategy involves hepatic glycogen mobilization, producing large amounts of glucose that are distributed to tissues where it functions both as a cryoprotectant and as a substrate for anaerobic ATP production. The present study examines the role of histone lysine methylation and demethylation in regulating liver proteins under anoxic conditions. Relative protein expression of seven histone methyltransferases (ASH2L-S, ASH2L-L, RBBP5, SETD8, SMYD2, ESET, SETD1), six lysine demethylases (KDM1A, KDM3B, KDM4A, KDM4B, KDM5A, KDM5C), and eight histone marks (H3K4me1, H3K4me2, H3K9me3, H3K27me3, H3K36me3, H3K79me3, H4K20me1, H4K20me3) were evaluated in wood frog liver under control, 4-hour, and 24-hour anoxia exposures. The data indicate that histone lysine methylation and demethylation contribute significantly to transcriptional regulation under anoxia. Specifically, H3K4, H3K36, and H3K79 methylation were associated with transcriptional activation, whereas H3K9, H3K27, and H4K20 methylation correlated with transcriptional repression. These findings highlight the dynamic role of epigenetic regulation in supporting hypometabolism and stress adaptation in freeze-tolerant wood frogs.

Hutchinson-Gilford Progeria Syndrome (HGPS) is a rare genetic condition characterized by features of accelerated aging, with a life expectancy of less than two decades. HGPS is commonly caused by a point mutation in the LMNA gene which codes for lamin A, a vital component of the nuclear lamina. The HGPS mutation activates a cryptic splice site and leads to production of a truncated, farnesylated form of lamin A referred to as "progerin." Progerin is also produced in small amounts in healthy individuals and has been implicated in normal aging. HGPS is associated with an accumulation of genomic DNA double-strand breaks (DSBs), and alterations in DSB repair. DSB repair in mammalian cells normally occurs by either homologous recombination (HR), an accurate, templated form of repair, or by DNA end-joining (EJ), a non-templated rejoining of DNA ends. EJ is error-prone, although a portion of EJ events occurs precisely with no alteration to joined sequences. Previously, we reported that over-expression of progerin increased EJ relative to HR and decreased the precision of EJ. In our current work, we designed a novel model experimental system using derivatives of thymidine kinase (tk)-deficient mouse fibroblasts and incorporating a loss-of-function assay to further explore progerins impact on EJ. We established cell lines containing an integrated copy of a functional herpes tk gene with an embedded recognition site for endonuclease I-SceI. We examined EJ at the nucleotide level following induction of a DSB within the tk gene by expression of I-SceI and subsequent selection for cells that lost tk gene function. Comparison of EJ products recovered from cells expressing progerin versus from cells not expressing progerin revealed that progerin expression provoked larger DNA deletions associated with DSB repair as well as recovery of multiple repair products from individual cells, suggesting progerin impedes re-joining of DNA ends.

In TMPRSS2 fusion-positive prostate cancer, ERR is involved in regulation of ERG and promotes the androgen receptor independent signaling in the cancer progression. The ERR binds to the ERREs (estrogen-related receptor response elements) present at -5042 bp of the TMPRSS2- promoter and enhances the ERG overexpression that causes prostate cancer progression. To dissect the structural basis of the ERR recognition to the TMPRSS2 promoter DNA, we have purified the full-length ERR (ERRFL), NTD deleted construct (ERR{Delta}NTD), and the DNA-binding domain (ERRDBD) proteins and performed the binding analysis with 30 bp TMPRSS2-promoter DNA (5' -AGTCCAAGGTCGGTGGATC ACAAGGTCAGG-3'). Circular dichroism analysis showed that all three ERR proteins adopt native secondary structures. DNA binding induced subtle changes in the secondary structures, while enhancing the thermal stability (Tm) of all ERRa proteins. Binding analysis showed that ERRDBD bound weakly to the DNA, whereas ERRFL and ERR{Delta}NTD exhibited substantially higher affinities ~120-fold and ~131-fold than ERRaDBD, respectively. Small-angle X-ray scattering (SAXS) analyses revealed a dimeric ERRFL structure and an ERRFL-DNA complex (2:1) structure in solution and fitted well with Alpha Fold model of apo and DNA bound complex of ERRFL. Furthermore, 100 ns dynamics simulations on apo and DNA-bound ERRa proteins showed that all proteins remained structurally stable, with flexibility largely confined to loop regions of ERRa proteins. Our biophysical, DNA binding and structural analyses have revealed the mechanism involved in ERR recognition of the TMPRSS2- promoter DNA, which provides insight into ERR-mediated transcriptional regulation and development of anticancer drugs against ERR-driven prostate cancer.

BackgroundPartner and Localizer of BRCA2 (PALB2) is a key tumor suppressor gene involved in homologous recombination-mediated DNA repair through its interactions with BRCA1 and BRCA2. Germline alterations in PALB2 have been associated with hereditary breast cancer risk; however, its broader molecular role in breast cancer progression and prognosis requires further investigation. MethodsA comprehensive in-silico analysis of PALB2 was performed using publicly available databases and bioinformatics platforms. Differential expression of PALB2 in breast cancer were evaluated using GEPIA2. Prognostic significance was assessed through Kaplan-Meier analyses for overall survival (OS) and disease-free survival (DFS). Protein-protein interaction (PPI) networks were constructed using STRING. Functional enrichment analyses of PALB2-associated genes were conducted using g. Mutational profiling of PALB2 in breast cancer was performed using cBioPortal with data from TCGA breast cancer cohorts. ResultsPALB2 expression was elevated in breast tumor tissues compared with normal breast tissues. Survival analyses revealed no statistically significant association between PALB2 expression and either overall survival (HR = 0.88, p = 0.44) or disease-free survival (HR = 0.74, p = 0.11). Protein interaction analysis revealed strong interactions between PALB2 and major DNA repair proteins including BRCA1, BRCA2, RAD51, RAD51C, FANCD2, and BRIP1. Functional enrichment analysis showed limited significant pathway enrichment, with only marginal transcription factor motif enrichment observed. Mutational analysis demonstrated diverse genomic alterations including missense mutations, truncating mutations, copy number gains, and shallow deletions. ConclusionThe findings support the biological relevance of PALB2 in breast cancer through its elevated expression and strong connectivity within DNA repair pathways. However, PALB2 expression alone does not appear to serve as an independent prognostic indicator. Further studies integrating genomic, transcriptomic, and clinical parameters are required to clarify its role in breast cancer progression and therapeutic response.

Language genes can be tentatively considered as a subset of cognitive genes, although they are often discussed separately. During the evolution of SNVs (single nucleotide variations) in cognition-related genes, do language genes and cognitive genes exhibit significantly different intensities of change at several key evolutionary moments--namely, the inflection points or derivative peak positions of similarity curves drawn from multi-SNV locus bases across samples? In this study, nine distance/similarity metrics (Bray-Curtis, Cosine, Pearson, Spearman, Hamming, Jaccard, Matching, Kulczynski, and Gower) were employed to analyze 413 samples from 11 taxonomic groups, targeting SNV loci in language/cognition-related genes (13,415 effective loci, approximately 400 loci per gene), with pp6 (Homo_sapiens.GRCh38) as the reference. For each method, sample similarities (defined as 1/(1+distance)) were independently sorted in ascending order to generate raw similarity scatterplots. Due to the large sample size and representativeness, the scatter density on the similarity curves was high, and no smoothing was applied. Derivative values were calculated from adjacent similarity differences to identify peaks of evolutionary rate change (top 10 peaks per method). Combined with functional annotations of 33 language/cognition-related genes, we quantified the difference scores and occurrence frequencies of the two gene categories at the peak positions. The results indicate that cognitive-related genes exhibit slightly higher occurrence frequencies in peak windows and higher average difference scores per gene than language genes. Comparative analysis of SNVs at the peak samples and their left-side windows revealed that at positions 381-382, all nine methods shared three intersecting mutation loci, involving language genes (NFXL1, SRGAP2, SRGAP2C); at positions 355-356, there was one intersecting mutation locus, involving a language gene (SRGAP2). This suggests that certain mutations in language genes may have played a distinctive role at critical junctures in the evolution of cognitive abilities.

Background and PurposePARP inhibitors have been evaluated in clinical trials for several cancers and Olaparib is FDA approved for treating BRCA deficient ovarian cancer. Numerous reports have suggested Poly(ADP-ribose) polymerase1(PARP1) overexpression in a variety of cancers including breast carcinomas and proposed the role of PARP1 in metastasis. However, the mechanism of PARP1 in regulating metastatic process in BRCA proficient and deficient TNBC is not studied thoroughly. In this study, we propose that PARP1 mediated breast carcinoma progression is gene transcription mediated, where it regulates several steps of pro-metastasis. Experimental ApproachPARP inhibitors effect on metastasis was monitored by migration and invasion assay, modulation in protein expression was assessed by proteomic analysis and further confirmed by immunoblotting. Chromatin immunoprecipitation was performed to study the transcriptional role of PARP1. Ectopic expression and siRhoGDI, and immunofluorescence assessed the cytoskeleton changes. PARP inhibitor was administered in xenograft mice to study metastasis. Immunohistochemical analysis was done on patient and mice tissues. Key resultsBreast cancer cells exhibited reduced migration and invasion due to PARP1 inhibition. PARP1 regulates expression of vimentin and RhoGDI and hence cytoskeletal rearrangement causing a change in migrating potential of a cell. Metastasis in mice was reduced upon PARP inhibition. PARP1 was identified to be a novel transcriptional regulator of RhoGDI. Furthermore, RhoGDI ectopic expression substantiated the PARP inhibitor effects, suggesting the PARP inhibitor downstream signaling to be mediated through RhoGDI. Conclusions and ImplicationsWe identified a novel aspect of PARP1 as promoter of metastasis via transcriptional regulation of RhoGDI. Assessing RhoGDI levels in TNBC patients might be useful to predict sensitivity to PARP inhibitors.

Valproic acid/sodium valproate (VPA) is a widely prescribed anticonvulsant and has also been used against certain tumor cells. It is a potent modulator of gene expression. Its ability to induce apoptosis has been well documented in HeLa cells. However, another form of cell death - mitotic catastrophe - has not yet been explored in VPA-treated HeLa cells. Here, we investigated the effects of VPA treatment on mitotic catastrophe characteristics, including morphological features and their frequencies, fluorescence intensity signals of caspase-2 and p53, and the expression and abundance of DNMT1 and DNMT3B. An increased frequency of mitotic catastrophe was observed not only morphologically, but also through enhanced induction of caspase-2, involvement of p53, at least under more drastic VPA treatment, but without a decrease in DNMT1 or DNMT3B levels. Additionally, enhancement of mitotic catastrophe coincided with a reduction in mitotic chromosome abnormalities. Increased DNMT3B expression following VPA action, may be favored by previously reported chromatin decondensation induced by this drug. Enhanced CpG methylation of specific DNA sites could thus be promoted. In conclusion, VPA was shown to trigger metabolic pathways linked to different forms of cell death in HeLa cells, supporting its oncosuppressive potential.

Meiosis is a fundamental process in producing both sperm and eggs, yet recombination landscapes often exhibit sexual differences, known as heterochiasmy. Since meiotic proteins are generally expressed in both sexes, the molecular mechanism driving heterochiasmy remains elusive. The -kleisin subunit gene of meiotic cohesin, Rec8, is expressed bisexually in mammals, while its putative teleost ortholog, rec8a, is expressed in a female-biased manner, presumably due to the presence of its paralog originating from the teleost-specific whole-genome duplication (TGD). Here, we elucidated the evolutionary history and expression dynamics of -kleisin genes across teleost lineages. Through comprehensive phylogenetic and synteny analyses, we revealed that major teleost lineages retain two copies of rec8 and rad21, with rec8 loci experiencing drastic chromosomal rearrangements immediately after the TGD. Using in situ hybridization and single-cell transcriptome data in medaka and zebrafish, we demonstrated a conserved sexually biased expression pattern: rec8a is predominantly female-biased, whereas rec8b exhibits male-biased expression during gametogenesis. Furthermore, comparative epigenetic analyses revealed that the conserved sexually biased expression is driven by lineage-specific cis-regulatory elements, rather than conserved ones. Motif analyses imply that regulatory rewiring by transcription factors, including foxl2l in particular, might have played a crucial role in the establishment and maintenance of this paralog divergence. Our findings highlight how whole-genome duplication and subsequent genomic and epigenetic rewiring subdivided the bisexual function of rec8, offering insights into sexually distinct meiotic regulation. HighlightsO_LITeleosts possess a unique -kleisin repertoire originating from the TGD. C_LIO_LITeleost rec8 paralogs exhibit conserved sex-biased expression during meiosis. C_LIO_LIDrastic genomic rearrangements after the duplication rewired the teleost rec8 loci. C_LIO_LIThe conserved expression pattern is governed by lineage-specific CREs. C_LIO_LIThose CREs harbor similar types of TFBSs such as Fox-family TFs. C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=94 SRC="FIGDIR/small/731870v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@c8c84dorg.highwire.dtl.DTLVardef@1d65668org.highwire.dtl.DTLVardef@c2d732org.highwire.dtl.DTLVardef@1be54a2_HPS_FORMAT_FIGEXP M_FIG C_FIG

Humans and other vertebrates contain two estrogen receptors (ERs), ER-alpha and ER-beta, which mediate the physiological actions of three estrogens: estrone (E1), estradiol (E2) and estriol (E3). Of these three estrogens, in vivo, E2 is the strongest transcriptional activator of ER-alpha and ER-beta, E1 is next most active, followed by E3. We studied transcriptional activation of human ER-alpha and ER-beta by E2, E1 and E3 in African green monkey kidney (COS-7) cells, which we compared with studies of estrogen stimulation of ER transcription in human em-bryonic kidney (HEK-293) cells. To our surprise, in COS-7 cells, E3 had the lowest half-maximal response (EC50) for human ER-alpha and ER-beta than either E2, which was second most active estrogen, or E1. In contrast, for human ER-alpha and ER-beta transfected into HEK-293 cells, E2 was the most active estrogen, followed by E1 and E3. Similar results were found in COS-7 cells and HEK-293 cells transfected with elephant shark ER-alpha and ER-beta. Thus, under some conditions, E3 is a more active estrogen than either E2 or E1. This suggests that E3 may be a novel physiological ligand for the ER in some mammalian cells.

Doublesex and mab-3 related (DMRT) genes encode a family of transcription factors central to sexual development across metazoa. DMRT genes are characterised by a highly conserved DNA binding domain (DM) while flanking regions may vary between species. Gene duplication and loss has shaped the diversity of the DMRT genes with several unresolved questions about their evolution. The most well characterised and conserved DMRT gene, DMRT1, functions as a sexual regulator universally in metazoans. In chicken, DMRT1 is located on the Z chromosome and acts as a dosage dependent primary sex determination gene. In therian mammals DMRT1 is autosomal, however, two copies are required for male development. Interestingly in the basal lineage of egg-laying mammals (monotremes), DMRT1 is localised on the X specific part of one of the X chromosomes. This provided the first evidence of a sex chromosome system with homology to the avian Z chromosome and raises questions about the function and evolution of DMRT1 in egg-laying mammals. To gain insight into the evolution of mammalian DMRT genes we performed sequence and expression analysis of monotreme DMRT genes and comparative analysis with other vertebrates. In monotremes, we identified DMRT genes 1-7, and show that DMRT8 is absent, suggesting that DMRT8 evolved in therian mammals after the divergence of monotremes. Sequence and expression analysis revealed multiple monotreme specific DMRT1 isoforms with additional protein-coding exons. The independent evolution of monotreme specific changes in DMRT1 may be the first indication of functional or regulatory differences in monotreme DMRT1. Article SummaryGenes in the Doublesex and mab-3 related (DMRT) family play important roles in sexual development across animals, but a comprehensive analysis of these transcription factors is lacking in the most basal mammalian lineage of monotremes. This comparative analysis of DMRT genes in monotremes and other vertebrates shows the conservation of DMRT genes 1- 7 but found no evidence of DMRT8 in monotremes or marsupial species, suggesting that this gene evolved in eutherians after the divergence of marsupials. The discovery of several monotreme specific isoforms and novel exons of the X linked DMRT1 reveals unique evolutionary changes in monotreme DMRT1.

Selective estrogen receptor modulators (SERMs) like tamoxifen are used to treat hormone receptor positive (HR+) breast cancers. Several models of in vitro acquired resistance to tamoxifen using HR+ breast cancer cell lines have been developed. There are few models of resistance to tamoxifen that are generated in vivo. Here, we generated a model of in vivo resistance to tamoxifen. We show that in vivo tamoxifen resistance is associated with loss of IGF1R. This loss is irreversible as it persists even when tamoxifen is removed. In vivo tamoxifen resistance is also associated with upregulation of insulin receptor, specifically the A isoform of IR (IR-A). These resistant cells show enhanced insulin sensitivity compared to the parental endocrine sensitive or in vitro acquired tamoxifen resistant cells. Finally, we demonstrate that in vivo resistance to tamoxifen results in enhanced proliferation in response to insulin. These studies establish that some mechanisms of in vivo resistance to tamoxifen differ from those observed for in vitro acquired resistance and increased dependence on insulin signaling drives endocrine resistance in HR+ breast cancer. Taken together, these studies present that targeting IR-A in combination with newer targets of tamoxifen resistance could be tested in endocrine resistant breast cancer.

Mutations in p53 and its 12 isoforms can alter its functions. As N-terminally truncated isoforms of p53 (delta40p53, delta133p53, and delta160p53) participate in tetramer formation, they are important regulators of cancer fate. Although delta40p53- and delta133p53-mediated regulation of cancer is well reported, the mechanism underlying delta160p53 production and its functional role remains unclear. We investigated the internal ribosomal entry site (IRES)-mediated translation of {Delta}160p53 and its role in cancer regulation. As differential synthesis of delta160p53 was observed under different stress conditions, IRES-mediated translation of this isoform was demonstrated using bicistronic luciferase constructs. No cryptic promoters or splicing sites were detected in the IRES sequence. Cell death and late apoptosis were significantly decreased, while proliferation, the number of cells in the S phase, and drug resistance were induced by delta160p53. Furthermore, delta160p53 did not induce p53-responsive promoters. RNA sequencing analysis of delta160p53 overexpression showed similar results, along with the inhibition of other tumor suppressor genes. Overall, our results provide insights into IRES-mediated translation of delta160p53, which can be considered a novel target for cancer treatment.