Molecular Biology Reports最新文献

Background: The ATP9A gene encodes a P4-type ATPase involved in phospholipid translocation, essential for vesicular trafficking and neuronal development. Pathogenic ATP9A variants cause autosomal recessive neurodevelopmental disorders characterized by intellectual disability and microcephaly, yet the impact of missense variants remains poorly understood.

Methods: A 7-year-old female patient with cognitive impairment, microcephaly, and developmental delay was admitted to Başakşehir Çam and Sakura City Hospital. Whole exome sequencing (WES) using Illumina technology identified a novel homozygous ATP9A variant, confirmed by Sanger sequencing and segregation analysis. In silico tools (RosettaFold, DynaMut, mCSM, SDM, DUET, AggreScan3D) assessed its structural impact. Quantitative real-time polymerase chain reaction (RT-qPCR) was conducted to evaluate the relative expression levels of ATP9A.

Results: WES revealed a homozygous missense variant, ATP9A: NM_006045.3:c.1091G > C:p.(Arg364Thr), classified as variant of uncertain significance based on ACMG guidelines (PP2, PM2, PM3). Protein modeling demonstrated reduced stability (ΔΔG = - 1.51 to - 0.26 kcal/mol), increased flexibility, and a 2.4-fold decrease in solvent accessibility. The variant disrupted polar and hydrophobic interactions within the P-type ATPase IV domain, thereby increasing aggregation propensity. Expression analysis revealed elevated ATP9A mRNA levels, suggesting a compensatory cellular response.

Conclusion: This novel ATP9A variant broadens the mutational spectrum of ATP9A-related neurodevelopmental disorders. Structural destabilization of the p.(Arg364Thr) protein may contribute to the patient's cognitive impairment and microcephaly, warranting further functional studies.

Background: External damage is a significant and treatable cause of cervical insufficiency (CI). This study evaluates a controlled-release drug delivery system combining platelet-rich plasma (PRP) with alginate hydrogel (Alg-PRP) to enhance cervical healing in a rat model.

Methods: Forty female Wistar rats were assigned to four groups (n = 10): Alg-PRP, PRP, PBS, and healthy control. Cervical injury was induced, and treatments were administered accordingly. Cervical regeneration was assessed using qRT-PCR, histopathology, and immunohistochemistry (IHC). Functional outcomes, including pregnancy rate and number of pups, were also analyzed.

Results: Alg-PRP hydrogel exhibited a porous structure, minimal toxicity, and sustained growth factor release. VEGF expression was significantly higher in the Alg-PRP group (p < 0.001), while MMP9 and TGF-β expression were reduced (p < 0.0001, p < 0.001). Collagen I and III levels were lower (p < 0.001, p < 0.05). Masson's Trichrome staining confirmed reduced fibrosis (p < 0.01). IHC demonstrated increased epithelial thickness, proliferation (p < 0.001, p < 0.0001), and angiogenesis (p < 0.01), alongside decreased fibrosis markers (p < 0.0001). The Alg-PRP group had the highest pregnancy rate (100%) and greater pup numbers.

Conclusion: Alg-PRP hydrogel significantly enhances cervical healing and reproductive outcomes, highlighting its potential as a novel therapeutic for cervical injuries.

Background: Soil contamination with Cadmium (Cd) is one of the major environmental issues facing the world, which poses a tremendous threat to plant growth. Heavy-metal ATPase (HMA), essential to regulate plants' metal homeostasis, has been extensively identified in abundant plant species. However, the HMA gene family members in Chrysanthemum indicum have not been identified.

Methods and results: In this study, we identified 10 CiHMAs and classified them into three subfamilies: I, II, and III. Transcriptome and qRT-PCR analyses demonstrated significant induction of CiHMA5 expression under Cd stress. CiHMA5 is situated in the chloroplast and cell membrane. Heterologous expression of CiHMA5 in Arabidopsis thaliana exhibits a Cd-tolerant phenotype with diminished Cd accumulation as well as enhanced antioxidant enzyme activity. Furthermore, CiHMA5 transgenic C. indicum plants also conferred a Cd-tolerant phenotype and lower Cd content, accompanied by higher transfer coefficients in shoots and leaves than wild-type (WT).

Conlusion: These findings established a theoretical groundwork for further delve into the role and regulatory mechanism of CiHMAs in Chrysanthemum under Cd stress.

Background: Selenium (Se) is an essential micronutrient for humans, yet its dietary availability largely depends on plant-based foods. In rice, Se uptake occurs mainly via sulfate transporters due to the chemical similarity between sulfate and selenate. While the role of transporters such as OsSULTR1;2 has been described in japonica rice, little is known about their regulation in indica aromatic cultivars like Super Basmati, which are naturally enriched in Se and widely consumed across Asia. This study aimed to characterize the transcriptional regulation of OsSULTR genes in Basmati rice under selenate exposure to identify candidate transporters contributing to Se biofortification.

Methods and results: Super Basmati seedlings were hydroponically grown under varying sulfate and selenate concentrations, and gene expression was analyzed in roots, shoots, and developing grains by qRT-PCR. Se accumulation was quantified using ICP-MS. Among high-affinity transporters, OsSULTR1;1 showed strong induction in root tissues under selenate supply and was persistently expressed in developing grains, indicating dual roles in uptake and grain loading. In contrast, OsSULTR1;2 and OsSULTR1;3 were shoot-specific with minimal induction. Group 3 transporters exhibited variable shoot-specific expression, with OsSULTR3;2 and OsSULTR3;3 showing notable induction during grain development. Se accumulation increased dose-dependently in roots and shoots, with efficient translocation to shoots and progressive enrichment in grains. Uptake was strongly pH-dependent, with maximal absorption at acidic pH (3.5).

Conclusions: Our findings highlight OsSULTR1;1 as the primary transporter mediating Se uptake and seed loading in Basmati rice, contrasting with OsSULTR1;2 in japonica rice. This study provides new molecular insights into Se accumulation in aromatic indica rice and identifies OsSULTR1;1 as a promising target for Se biofortification strategies to improve dietary nutrition.

Objective: Bacteria frequently encounter sub-inhibitory concentrations of antibiotics within host tissues and natural environments, where these exposures can function as regulatory signals rather than growth inhibitors. Streptococcus pyogenes, an important human pathogen, transitions between asymptomatic colonization and invasive disease through complex regulation of virulence factors and stress responses. In this article we aim to show that there is alteration in virulence of S. pyogenes on exposure to CWA antibiotics. In clinical practice, cell wall-active antibiotics remain the cornerstone of therapy against S. pyogenes, therefore understanding their ability to modulate virulence and stress responses is critical.

Methods: S. pyogenes was exposed to sub-MIC levels of penicillin, bacitracin, and colistin. Capsule formation, biofilm development, and macrophage interactions were assessed phenotypically. Transcriptional analysis of various important virulence determinants (speB, slo, hasA) and oxidative stress response gene (sodA, ahpC, gpo) were analysed. Adhesion and invasion assays were performed using murine macrophages. The activity of the serine/threonine kinase (stk) and oxidative stress regulator (spx) was also examined. Change in morphology in presence of CWA antibiotics was assessed by staining and measuring cell size.

Results: The results demonstrate that sub-MIC of CWA antibiotics significantly altered capsule formation, enhanced biofilm development, and increased adhesion and invasion of macrophages, indicating a potential role in immune evasion and persistence. Transcriptional analysis revealed upregulation of both virulence-associated and oxidative stress defense genes, alongside increased activity of stk and spx.

Conclusion: Sub-inhibitory concentrations of CWA antibiotics act as environmental cues, reprogramming molecular regulatory networks that contribute to the shift from colonization to invasive disease. Our results highlight that beyond their antimicrobial function, CWAs influence key molecular pathways that may inadvertently promote persistence and pathogenicity.

Circular RNAs (circRNAs) are covalently closed RNA transcripts produced by back-splicing. First identified in plant viroid in 1976, they were long regarded as "splicing noise" or transcriptional byproducts. However, high-throughput sequencing has revealed thousands of circRNAs in eukaryotic cells, indicating that they are widespread and conserved. These molecules lack 5' caps and 3' poly(A) tails, making them resistant to exonucleases. Their circular structure confers exceptional stability, and many circRNAs are expressed in a tissue-specific manner, making them attractive biomarkers. Functionally, circRNAs regulate gene expression at multiple levels. Many act as "sponges" for microRNAs or RNA-binding proteins, modulating mRNA stability and translation; others influence transcription, alternative splicing, or chromatin architecture, and some can be translated into peptides. In human biology, circRNAs have diverse roles: dysregulated circRNAs contribute to tumorigenesis and shape the tumor microenvironment; they are abundant in the brain and implicated in neurodevelopment and neurodegenerative diseases; and they modulate immune responses (for example, via T cells, NK cells, and macrophages). Experimentally, circRNAs are detected by RNase R-enriched RNA sequencing and bioinformatics pipelines that identify unique back-splice junction reads. Predicted circRNAs are then validated by RT-PCR across the circular junction. The stability and versatility of circRNAs have inspired therapeutic applications, such as engineered circRNA vaccines or miRNA sponges. Overall, these findings underscore that circRNAs constitute a powerful and versatile class of gene regulators with significant diagnostic and therapeutic potential, although translating this potential into clinical success requires overcoming current challenges. Nonetheless, significant challenges in delivery, specificity, and immunogenicity remain to be addressed before clinical translation.