DNA

Background: Exon 1 of the gene encoding for the androgen receptor (AR) contains a polymorphic sequence of variably repeated CAG triplets ranging from 11 to 36. The number of triplets appears to inversely correlate with receptor transcriptional activity, conditioning the peripheral effects of testosterone. Methods: We conducted a narrative review to explore the current evidence regarding the relationship between the number of CAG repeats and the human reproductive system. Results: We found several articles that investigate the relationship between CAG polymorphism and the male reproductive system, suggesting a possible modulatory effect on spermatogenesis, sexual function, prostate cancer, and testicular cancer. Similarly, in women, evidence has emerged to support a possible relationship between CAG repeat number and breast cancer, polycystic ovary syndrome (PCOS), and recurrent spontaneous abortions (RSAs). Unfortunately, the data in the current literature are largely discordant, largely due to an important influence of ethnicity on the variability of the CAG polymorphism, and partly due to the quality of the available studies. Conclusions: In the current state of the art, the study of CAG polymorphism does not have a sufficient literature base to allow its use in common clinical practice. However, it represents an interesting research target and, in the future, as new evidence emerges, it could help to elucidate some pathogenetic aspects of human reproductive disorders. Full article

Background: The pyrrolobenzodiazepine (PBD) dimer SJG-136 reached Phase II clinical trials in ovarian cancer and leukaemia in the UK and USA in the 2000s. Several structural analogues of SJG-136 are currently in clinical development as payloads for Antibody-Drug Conjugates (ADCs). There is growing evidence that PBDs exert their pharmacological effects through inhibition of transcription factors (TFs) in addition to arrest at the replication fork, DNA strand breakage, and inhibition of enzymes including endonucleases and RNA polymerases. Hence, PBDs can be used to target specific DNA sequences to inhibit TFs as a novel anticancer therapy. Objective: To explore the ability of SJG-136 to bind to the cognate sequences of transcription factors using a previously described HPLC/MS method, to obtain preliminary mechanistic evidence of its ability to inhibit transcription factors (TF), and to determine its effect on TF-dependent gene expression. Methods: An HPLC/MS method was used to assess the kinetics and thermodynamics of adduct formation between the PBD dimer SJG-136 and the cognate recognition sequence of the TFs NF-κB, EGR-1, AP-1, and STAT3. CD spectroscopy, molecular dynamics simulations, and gene expression analyses were used to rationalize the findings of the HPLC/MS study. Results: Notable differences in the rate and extent of adduct formation were observed with different DNA sequences, which might explain the variations in cytotoxicity of SJG-136 observed across different tumour cell lines. The differences in adduct formation result in variable downregulation of several STAT3-dependent genes in the human colon carcinoma cell line HT-29 and the human breast cancer cell line MDA-MB-231. Conclusions: SJG-136 can disrupt transcription factor-mediated gene expression, which contributes to its exceptional cytotoxicity in addition to the DNA-strand cleavage initiated by its ability to crosslink DNA. Full article

Background/Objectives: Lung cancer ranks as the leading cause of cancer-related deaths globally and is highly associated with cisplatin resistance due to both intrinsic and extrinsic mechanisms. Proliferating Cell Nuclear Antigen (PCNA) plays a critical role in molecular processes, such as DNA replication and repair, chromatin structure maintenance, and cell cycle progression. PCNA is known as a molecular marker for proliferation and an excellent inhibition target to shut down highly proliferative cells. One of the mechanisms of cisplatin resistance is the increase in DNA repair, and studies have reported an association between PCNA, lung cancer, and cisplatin treatment. The present study aimed to characterize the absence of PCNA in A549 lung adenocarcinoma cells. Methods: Employing a CRISPR/Cas9 gene-editing approach, we generated a monoclonal cell culture, termed PKO (PCNA knockout). Results: PKO cells exhibited a residual PCNA expression, significantly decreased clonogenic potential and ubiquitylation at K164 residue. IC50 assay suggested that PKO cells could not acquire cisplatin resistance when compared to PX. After cisplatin treatment, PKO cells presented impaired ubiquitylation and did not have increased STAT3 phosphorylation (Tyr705), a previously characterized mechanism of cisplatin resistance. Conclusions: We suggest that PCNA participates in cisplatin resistance in A549, partially by DNA damage tolerance through failure on PCNA monoubiquitylation, and its inhibition may be an approach to circumvent cisplatin resistance. Full article

Epigenetic modifications affecting DNA, RNA, and proteins can alter the functional state of a gene and heavily interfere with gene expression. These processes are typically transient, and the predominant form of inheritance is mitotic, with a small fraction of transgenerational modifications. It is therefore reasonable to ask what forces drive this acquisition in living beings, where certain variations in phenotype do not correspond to changes in the DNA sequence. Full article

In this research, we induced acute kidney injury (AKI) by ischemia-reperfusion injury (IRI), one of its main causes. Then, we assessed kidney dysfunction by CRE (creatinine)/BUN (serum blood urea nitrogen) levels and histological analysis. Surprisingly, kidney macrophages, initially not expressing MafB and c-Maf, expressed both of them 48 h after bilateral ischemia renal disease (double IRD; dIRD), supporting their possible roles in the disease. We speculated that the M2 macrophages involved in AKI repair might be the source of MafB and c-Maf after injury and that these two transcription factors could have a significant role in the disease. Considering that IL-4/IL-13-induced M2a is the main contributor to AKI recovery and that MafB is upregulated under the effect of these two cytokines combined, we chose to focus on MafB analysis and aimed to examine its potential role in IRD. Previous studies have not examined the role of MafB in ischemic renal disease (IRD). In this study, we demonstrated a significant loss of brush borders, accumulation of intraluminal debris, and extensive damage to the anatomical structure of the MafB^f/f::Lys-Cre mice kidneys compared to their littermates, MafB^f/f, which are considered as a negative control in the entire paper. This was marked by the enlarged tubules, a significant decrease in mature macrophages (F4/80⁺ cells), and, therefore, worsening of the disease in the absence of MafB and delay/failure of the early signs of ischemia recovery. Importantly, these MafB cKO mice presented higher mortality, caused by the abrogation of the intraluminal debris clearance, and died after 48 h from IRD, suggesting the involvement of MafB in the signaling pathway of this pathology. Therefore, we found evidence that MafB attenuates IRD. Full article

Background: Colorectal cancer (CRC) is the third most diagnosed cancer globally and the second leading cause of cancer-related deaths. Despite advancements, metastatic CRC (mCRC) has a five-year survival rate below 20%. Next-generation sequencing (NGS) is recommended nowadays to guide mCRC treatment; however, its clinical utility when compared with traditional molecular testing in mCRC is debated due to limited survival improvement and cost-effectiveness concerns. Methods: This retrospective study included mCRC patients (≥18 years) treated at a single oncology centre who underwent NGS during treatment planning. Tumour samples were analysed using either a 52-gene Oncomine™ Focus Assay or a 500+-gene Oncomine™ Comprehensive Assay Plus. Variants were classified by clinical significance (ESMO ESCAT) and potential benefit (ESMO-MCBS and OncoKBTM). The Mann–Whitney and Chi square tests were used to compare characteristics of different groups, with significance at p < 0.05. Results: Eighty-six metastatic colorectal cancer (mCRC) patients were analysed, all being MMR proficient. Most cases (73.3%) underwent sequencing at diagnosis of metastatic disease, using primary tumour samples (74.4%) and a focused NGS assay (75.6%). A total of 206 somatic variants were detected in 86.0% of patients, 31.1% of which were classified as clinically significant, predominantly KRAS mutations (76.6%), with G12D and G12V variants as the most frequent. Among 33.7% RAS/BRAF wild-type patients, 65.5% received anti-EGFR therapies. Eleven patients (12.8%) had other actionable variants which were ESCAT level I-II, including four identified as TMB-high, four KRAS G12C, two BRAF V600E, and one HER2 amplification. Four received therapies classified as OncoKbTM level 1–2 and ESMO-MCBS score 4, leading to disease control in three cases. Conclusions: NGS enables the detection of rare variants, supports personalised treatments, and expands therapeutic options. As new drugs emerge and genomic data integration improves, NGS is poised to enhance real-world mCRC management. Full article

TRIP13 is a member of the large AAA+ ATPase protein superfamily that plays a crucial role in the precise segregation of chromosomes during mitosis. The abnormal function of TRIP13 has diverse functions, including mitotic processes, DNA repair pathways, and spindle assembly checkpoints, which may contribute to chromosomal instability (CIN). Emerging evidence suggests that the overexpression of TRIP13, observed in many cancers, plays a significant role in drug resistance, autophagy, and immune invasion. Recently, significant advances have been made in identifying TRIP13-associated signaling pathways that have been implicated in cancer progression. Several small molecules that specifically inhibit TRIP13 function and reduce cancer cell growth have been developed. Combination treatments, including TRIP13 inhibitors and other anticancer drugs, have shown promising results. While these findings are promising, TRIP13 inhibitors are awaiting clinical trials. This review discusses recent progress in understanding the oncogenic function of TRIP13 and its possible therapeutic targets, which could be exploited as an attractive option for cancer management. Full article

Background/Objectives: One of the significant challenges in forensic casework is the analysis of samples with degraded or poorly concentrated genetic material. The utilisation of the GlobalFiler™ and Yfiler Plus™ kits has unquestionably enhanced the efficacy of genetic profiling in challenging samples, facilitating the analysis of alleles that were previously undetectable with alternative kits. Therefore, the main objective of this work was to verify the efficiency of these kits in analysing forensic samples, progressively reducing the amplification volumes. To further optimise genetic profiling, it was essential not only to assess the behaviour of the alleles but also to prevent allelic loss. Methods: A series of reaction volume reduction studies were conducted, evaluating the performance of genetic profiles in both controlled samples (positive controls) and low template DNA samples (0.01 ng/µL). Results: The results demonstrate that it is effective to obtain complete genetic profiles from the amplification of optimal samples in reduced volumes of 12, 6 or 3 µL with GlobalFiler™ and Yfiler™ Plus. Conclusions: The limiting factor in obtaining complete genetic profiles is the amount of DNA available, rather than the amplification volume. Furthermore, reducing the amplification volume from DNA extracts of low template DNA samples proportionally increases the number of allelic dropouts. Full article

Background/Objectives: Culex species mosquitoes are globally distributed and transmit several pathogens that impact animal and public health, including West Nile virus, Usutu virus, and Plasmodium relictum. Despite their relevance, Culex species are less widely studied than Aedes and Anopheles mosquitoes. To expand the genetic tools used to study Culex mosquitoes, we previously developed an optimized plasmid for transient Cas9 and single-guide RNA (sgRNA) expression in Culex quinquefasciatus cells to generate gene knockouts. Here, we established a monoclonal cell line that consistently expresses Cas9 and can be used for screens to determine gene function or antiviral activity. Methods: We used this system to perform the successful gene editing of seven genes and subsequent testing for potential antiviral effects, using a simple single-guide RNA (sgRNA) transfection and subsequent virus infection. Results: We were able to show antiviral effects for the Cx. quinquefasciatus genes dicer-2, argonaute-2b, vago, piwi5, piwi6a, and cullin4a. In comparison to the RNAi-mediated gene silencing of dicer-2, argonaute-2b, and piwi5, our Cas9/sgRNA approach showed an enhanced ability to detect antiviral effects. Conclusions: We propose that this cell line offers a new tool for studying gene function in Cx. quinquefasciatus mosquitoes that avoids the use of RNAi. This short study also serves as a proof-of-concept for future gene knock-ins in these cells. Our cell line expands the molecular resources available for vector competence research and will support the design of future research strategies to reduce the transmission of mosquito-borne diseases. Full article

Background: Rice, one of the main foods in Brazil and the world, is sensitive to chilling (0–15 °C), especially in the germination and reproductive stages. Chilling causes delayed germination and affects coleoptile elongation at the S3 stage (needlepoint), causing poor plant establishment, stunted growth, and non-vigorous plants, also impacting weed management. Elucidating the mechanisms responsible for resilience under cold conditions helps the development of tolerant cultivars. Transcription factors (TFs) act in stress response signaling, making them indispensable in the tolerance mechanism. Objective: Thus, this study aimed to identify and characterize the expression profile of transcription factors in the response to chilling stress in rice at the germination stage. Methods: To determine the transcriptional profile of 2408 genes belonging to 56 TF families, RNAseq was performed on the shoot tissue of seedlings of Oro (chilling-tolerant) and Tio Taka (chilling-sensitive) genotypes grown under control conditions (25 °C) and chilling stress (13 °C) until the S3 stage. Results: Of the total genes analyzed, 22% showed significant differential expression in the analyzed cultivars. There were 117 genes that showed significant differential expression in the tolerant cultivar, 60 of which were downregulated and 57 upregulated. In the sensitive cultivar, 248 genes had a significant differential expression, of which 98 genes were downregulated and 150 genes were upregulated. A total of 170 genes encoding TFs were commonly and significantly differentially expressed in the tolerant and sensitive genotypes. Conclusions: Here, we revealed potential new targets involved in the regulation of chilling stress in rice at the S3 stage. Full article

The detection of viral DNA is considered crucial in both diagnosis and prognosis. Nowadays, molecular diagnostic approaches represent the most promising tools for the clinical detection of viral infections. This review aims to investigate the most used and promising DNA-based technologies for viral detection, focusing on herpesviruses because of their ability to undergo latent and reactivation cycles, persisting lifelong in the host in association with several diseases. Molecular technologies, such as PCR-based assays, enhance sensitivity and specificity in identifying viral DNA from clinical samples such as blood, cerebrospinal fluid and saliva, indicating PCR and its derivatives as the gold standard methods for herpesvirus detection. In conclusion, this review underscores the need for continuous innovation in diagnostic methodologies to address the complexities of herpesvirus identification in different clinical samples. Full article

Cellular senescence is a response to endogenous and exogenous stresses, including telomere dysfunction, oncogene activation, and persistent DNA damage. In particular, radiation damage induces oxidative base damage and bond breaking in the DNA double-helix structure, which are treated by dedicated enzymatic repair pathways. In this review, we discuss the correlation between senescence and the accumulation of non-repaired single-strand breaks, as can occur during radiation therapy treatments. Recent in vitro cell irradiation experiments using high-energy photons have shown that single-strand breaks may be preferentially produced at the borders of the irradiated region, inducing senescence in competition with the apoptosis end-point typically induced by double-strand breaks. Such a particular response to radiation damage has been proposed as a possible cause of radiation-induced second primary cancer, as cells with an accumulation of non-repaired single-strand breaks might evade the senescent state at much later times. In addition, we highlight the peculiarities of strand-break repair pathways in relation to the base-excision pathway that repairs several different DNA oxidation defects. Full article

Background/Objectives: This study explores the genome sequencing data from the infection of Pseudomonas fluorescens UFV 041 by the bacteriophage Pijolavirus UFJF_PfSW6, aiming to identify and characterize prophages induced in the host bacterium during the infection. Methods: Scaffolds from sequencing data were analyzed, and reads were mapped to identify potential prophages using phage-to-host coverage metrics. The putative prophage scaffold was annotated, taxonomically classified, and its integration in the host bacterium was verified by PCR amplification of two target genes. We also tested whether mitomycin treatment could induce the prophage to enter the lytic cycle. Results: The prophage UFJF_PfPro was identified with a high phage-to-host coverage ratio. Its genome is 32,700 bp in length, containing 42 genes, 3 terminators, and 11 promoters, with 98.84% completeness. PCR confirmed its integration into P. fluorescens UFV 041, but mitomycin treatment did not induce the lytic cycle. The UFJF_PfPro genome shares 38.60% similarity with the closest lytic phages in the Phitrevirus genus, below genus and species assignment thresholds. A viral proteomic tree clustered UFJF_PfPro with Phitrevirus in a clade representing the Peduoviridae family. Conclusions: The UFJF_PfPro is a prophage integrated into the P. fluorescens UFV 041 genome, but we were unable to induce it to enter the lytic cycle using mitomycin treatment. The genome of UFJF_PfPro encodes all structural proteins typical of the Caudoviricetes class and shares low genomic similarity with species of the genus Phitrevirus, suggesting that UFJF_PfPro represents a new genus and species within the Peduoviridae family. Full article

The purpose of this study is to improve the identification of Culicidae species from the Vale Ribeira region, São Paulo state, Brazil. Adults were collected in the municipalities of Cananeia and Pariquera-Açu and morphologically identified. Molecular analyses were performed on sequences of COI barcode and a fragment of the D2 expansion of the 28S ribosomal RNA gene generated from field collected mosquitoes. The analyses included species delimitation, phylogeny, and interspecific genetic distances using the Kimura 2-parameter model. Species included in the analyses were Aedes perventor, Aedes scapularis, Aedes serratus/Aedes nubilus, Aedes serratus s.s., Aedes terrens, Haemagogus capricornii, Haemagogus leucocelaenus, Haemagogus janthinomys, Kerteszia bellatrix, Kerteszia cruzii, Psorophora ferox, Psorophora forceps, Sabethes conditus, and Wyeomyia confusa. COI sequences from specimens collected at other localities were included in the analysis for comparison. Results of barcode RESL analysis showed that specimens of Ps. ferox and Hg. janthinomys split into three clusters for each species. Similarly, sequences of Ke. bellatrix and Ke. cruzii were recovered in two groups for each species. Distinct from other species included in analyses, Ps. ferox and Ps. forceps shared 100% similarity in the D2 fragment sequenced. Overall, the analysis of COI barcode sequences revealed the following key findings: (1) the presence of subclades within Hg. janthinomys, with its division into three groups suggests that this species may represent a species complex; (2) Ke. bellatrix from the Atlantic tropical rainforest shares 95.59% sequence similarity with a specimen from the type locality, indicating that specimens from Southeastern Brazil may belong to an unidentified species within the Ke. bellatrix complex; (3) Ke. cruzii also represents a species complex; and (4) D2 sequences successfully identified most species studied, apart from Ps. forceps and Ps. ferox. Full article

Background/Objectives: DAPK-1 plays a crucial role among molecules that may be affected by DNA hypermethylation. The aim of this study is to investigate the DNA methylation of DAPK-1 gene in oral potentially malignant disorders (OPMDs) and oral squamous cell carcinoma (OSCC) compared to normal oral epithelium and to evaluate the possible role of methylated DAPK-1 as an indicator of the early onset of malignant transformation of oral potentially malignant disorders. Methods: The paraffin embedded tissue samples were retrieved from the archives of the Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, Greece and St Lukas Hospital of Thessaloniki, Greece during the period of 2014–2019. The tissue samples included 83 OPMDs samples, 39 OSCC samples and 12 samples of normal oral epithelium. The PCR process followed, targeting four different DAPK-1 gene primers. Results: Regarding OSCC, it was found that all 39 OSCCs samples were methylated in DAPK-1 promoter region, whereas only 2 out of 12 normal tissues samples showed DAPK-1 promoter hypermethylation (p < 0.001 Fisher’s exact test). A total of 17 out of 83 OPMDs were DAPK-1 methylated (five erosive oral lichen planus samples, three non-dysplastic oral leukoplakias, eight mildly dysplastic oral leukoplakias and one sample belonging to the group of moderately and severely dysplastic oral leukoplakia). Conclusions: Since epigenetic changes occur early in carcinogenesis and are potentially reversible, they could be used as disease biomarkers for diagnosis, prognosis and prediction, as well as therapeutic targets. DAPK-1 methylation is mostly present in the early stages of dysplasia as well as in all cases of oral cancer. Full article

Living systems are capable on the one hand of eliciting a coordinated response to changing environments (also known as adaptation), and on the other hand, they are capable of reproducing themselves. Notably, adaptation to environmental change requires the monitoring of the surroundings, while reproduction requires monitoring oneself. These two tasks appear separate and make use of different sources of information. Yet, both the process of adaptation as well as that of reproduction are inextricably coupled to alterations in genomic DNA expression, while a cell behaves as an indivisible unity in which apparently independent processes and mechanisms are both integrated and coordinated. We argue that at the most basic level, this integration is enabled by the unique property of the DNA to act as a double coding device harboring two logically distinct types of information. We review biological systems of different complexities and infer that the inter-conversion of these two distinct types of DNA information represents a fundamental self-referential device underlying both systemic integration and coordinated adaptive responses. Full article

Separation of duplex strands of nucleic acids is a vital process in the nucleic acid metabolism and survival of all living organisms. Helicases are defined as enzymes that are intended to unwind the double-stranded nucleic acids. Helicases play a prominent role in the cold adaptation of plants and bacteria. Cold stress can increase double-strand DNA breaks, generate reactive oxygen species, cause DNA methylation, and stabilize the secondary structure of RNA molecules. In this review, we discuss how helicases play important roles in adaptive responses to cellular stress caused by low temperature conditions, particularly in bacteria and plants. We also provide a glimpse of the eminence of helicase function over nuclease when an enzyme has both helicase and nuclease functions. Full article

Genetic engineering has revolutionized our ability to modify microorganisms for various applications in agriculture, medicine, and industry. This review examines recent advances in genetic engineering techniques for bacteria, fungi, and oomycetes, with a focus on CRISPR-Cas systems. In bacteria, CRISPR-Cas9 has enabled precise genome editing, enhancing applications in antibiotic production and metabolic engineering. For fungi, despite challenges associated with their complex cell structures, CRISPR/Cas9 has advanced the production of enzymes and secondary metabolites. In oomycetes, significant plant pathogens, modified Agrobacterium-mediated transformation, and CRISPR/Cas12a have contributed to developing disease-resistant crops. This review provides a comparative analysis of genetic engineering efficiencies across these microorganisms and addresses ethical and regulatory considerations. Future research directions include refining genetic tools to improve efficiency and expand applicability in non-model organisms. This comprehensive overview highlights the transformative potential of genetic engineering in microbiology and its implications for addressing global challenges in agriculture, medicine, and biotechnology. Full article

Objective: The study aimed to optimize protocols for the joint extraction of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) from 0.025 × 10⁶ CFU of Candida albicans, targeting to overcome the challenges in the extraction of these genetic materials. Materials and methods: From this, treated silicon carbide (SiC) granules were added to fungal samples from methods 1, 2, and 3 obtained from aliquots of BHI or Sabouraud medium to cause cell lysis and enable the isolation of these macromolecules by phenol and chloroform. The concentration and integrity of the extracted nucleic acids were analyzed, respectively, by spectrophotometry using the A₂₆₀/A₂₈₀ ratios and 1% agarose gel electrophoresis. Results: Therefore, method 3 is the one that most comprises samples considered pure of both DNA and RNA, simultaneously. Furthermore, the presence of intact RNAs corresponding to the base pair size such as 5.8 S rRNA and tRNA was verified during electrophoresis, considering the particularities of RNA, which makes it very unstable and easily degraded. Conclusions: Thus, it results in a faster and simpler method in addition to obtain promising results using minimal amounts of biological sample and offering a valuable alternative for small laboratories to work with molecular biology. Full article