Molecular Biology Reports最新文献

Background: Astrocytes are extensively utilized as starting cells for neuronal conversion. Our previous study discovered that a portion of primary cultured mouse neonatal cortical astrocytes can be directly converted into neurons after exposure to a neurogenic induction condition. Recent in vivo studies have demonstrated astrocyte heterogeneity in terms of their developmental origin, molecular profile, physiology, and functional outputs. We hypothesized that the heterogeneity of primary astrocytes in our study could influence their conversion potential.

Methods and results: We performed single-cell RNA sequencing on cells harvested at key time points during in vitro astrocyte-to-neuron conversion, specifically on Day 1 and Day 9. Through single-cell RNA sequencing analysis, we identified several subpopulations of astrocytes, labeled as Astrocyte 1 to Astrocyte 3, based on distinct gene expression patterns. Pseudotime trajectory analysis predicted the existence of three distinct cell states throughout the conversion process. Astrocyte 3 exhibited a higher propensity for neuronal conversion, with proliferation genes like Mki67 being highly expressed. Additionally, several candidate genes were identified as potentially crucial in the conversion process. Astrocyte 3 is considered a unique subtype population of astrocytes.

Conclusions: Our investigation underscores the diversity of primary neonatal cortical astrocytes and provides critical insights into the potential for astrocyte-to-neuron conversion, which may be harnessed to enhance the efficiency of this astrocyte-neuron conversion process.

SLC7A11, often called xCT, belongs to the SLC family of transporters, which mediates the cellular influx of cystine and the efflux of glutamate. These transport processes are crucial for synthesizing GSH, enhancing the cell's ability to mitigate oxidative stress (OS). Emerging studies highlight the pivotal role of OS in triggering and exacerbating various metabolic and endocrine disorders, underlining the critical importance of regulating SLC7A11 expression levels. This study reviews the diverse roles of SLC7A11 in endocrine and metabolic diseases, examining its relationship with the metabolism of three key nutrients: proteins and amino acids, carbohydrates, and lipids. Additionally, the involvement of SLC7A11 in the onset and development of various common endocrine and metabolic disorders is analyzed. Additionally, it provides an overview of the current clinical and experimental use of SLC7A11 inhibitors and agonists. This review aims to offer insightful perspectives into the involvement of SLC7A11 in endocrine and metabolic pathologies and to foster the development of innovative therapeutic strategies that target SLC7A11.

Background: Analysis of binding patterns of biomolecules underpin new paradigms for trait engineering. One way of designing early flowering crops is to manipulate genes controlling flowering time. SOC1, a central integrator of flowering, is downregulated by SVP. In amphidiploid Brassica juncea, flowering is plausibly mediated by combinatorial interactions involving natural variants of SOC1 promoter and SVP protein homologs. Although fluctuating temperatures influence energetics of molecular interactions and phenotypes, mechanistic insights on these remain unknown. Herein, we report diversity in 50 homologs of SVP proteins from 25 Brassicaceae species.

Materials and methods and results: Sequence and phylogenetic analysis of 9 natural variants of B. juncea SVP revealed differences in MIKC domains and sub-genome of origin. Generation and refinement of 15 SVP protein models (natural and hypothetical) using I-TASSER and ALPHAFOLD, and 3 SOC1 promoter fragments using 3D-DART, revealed structural diversity. Notwithstanding, binding affinity of 48 docked complexes analysed using HADDOCK and PreDBA were similar. Analysis of 27 docked complexes for distribution of shared or unique binding patterns and type of molecular contacts (π-π stacking, hydrophobic interactions, Van-der-Waals forces, H-bonds) using PyMOL, CCP4i, DNAproDB, PremPDI and DIMPLOT revealed extensive variation implicating compensatory mutations in preserving binding affinity. Yeast one-hybrid assays validated binding potential predicted in docked complexes. Conserved amino-acid and nucleotide residues involved in non-covalent interactions were identified. Computational alanine substitution established cruciality of amino-acid hotspots conferring stability to docked complexes.

Conclusions: Our study is important as identification of crucial amino-acid hotspots is essential for rational protein design. Targeted mutagenesis resulting in modified binding spectrum of regulatory proteins suggests a way forward for trait engineering.

Background: Rice is susceptible to several major and minor diseases, with blast disease caused by Magnaporthe oryzae being a significant constraint, leading to substantial economic losses worldwide. Exploiting genetic resistance in cultivars is a preferred strategy for managing this disease, offering an alternative to chemical control.

Methods and results: The objective of this study was to identify advanced breeding lines (ABLs) with blast resistance, superior yield, and good grain quality using Marker-Assisted Selection (MAS). Leaf blast resistance screening revealed that 25 ABLs exhibited moderate resistance. Molecular analysis with 10 polymorphic markers linked to blast resistance genes (Pi1, Pi2, Pi9, Pi37, Pi38, Pi39, Pi54, Pita, Pitp, and Piz5) identified the highest number of positive alleles (8) in MTU1061, IR36, and SVGP-26. Additionally, seven ABLs (SVGP-1, SVGP-14, SVGP-23, SVGP-37, SVGP-38, SVGP-39, and SVGP-48) showed co-segregation of markers with blast resistance. Genetic diversity analysis revealed significant variability among the genotypes, indicating diverse genetic backgrounds. Based on their yield performance, quality traits, and resistance to blast, five parents (NLR 34449, NLR 40024, MTU 1061, MTU 3626, and IR 36) and five ABLs (SVGP-13, SVGP-16, SVGP-40, SVGP-47, and SVGP-32) were selected for further yield trials.

Conclusion: The study identified high-yielding, blast-resistant lines with good grain quality and diverse genetic backgrounds as promising donor sources for improving blast resistance in rice breeding programs. These findings enhance the genetic base for developing resistant rice cultivars with improved agronomic traits.

Since the 1990s, fatty acids (FA) have drawn significant industrial attention due to their diverse applications creating a demand for biological systems capable of producing high FA titers. While various strategies have been explored to achieve this, many of the conventional approaches rely on extensive genetic manipulations, which often result in strain instability, thus limiting its potential to yield better FA titers. Moreover, stresses such as pH, osmotic, and oxidative imbalances generated during FA production aggravate these challenges, further limiting FA titers. Under stress conditions, the cellular system responds by regulating stress-response proteins to bring about homeostasis. Recent findings suggest that transmembrane proteins, regulators of two-component systems, and cytoplasmic regulators can be strategically leveraged to address the problems related to stress-induced strain instability. Thus, non-conventional genetic targets, like chaperones (e.g., heat shock proteins) and DNA-binding transcriptional regulators (e.g., RcdA), which are not directly involved in FA metabolism, represent promising candidates to enhance strain stability and FA yields. Tools like Opt-Box and Weighted Gene Co-expression Network Analysis (WGCNA) serve as excellent platforms for understanding the cross-talk between these regulators and downstream enzymes. This review emphasizes the need for a shift towards identifying novel genetic targets by employing advanced in silico analysis and explains several molecular techniques that can aid in strain construction. Lastly, it discusses certain non-conventional gene targets that can help to overcome strain instability arising due to various stresses generated during/due to FA production.

Background: SARS-CoV-2 infection is marked by an excessive inflammatory response, leading to elevated production of pro-inflammatory cytokines through activation of intracellular pathways like mitogen-activated protein kinase (MAPK). Viruses can use the MAPK signaling pathway to their advantage, but the relationship of this pathway to the severe SARS-CoV-2 period has not been fully elucidated. MAP2K4 is involved in the MAPK signaling pathway and affects cellular processes such as cell-cell junction, cell proliferation, differentiation and apoptosis.

Methods and results: In this study, we sought to determine the associated biomarkers that are involved in the MAP2K4 pathway and elucidate its possible roles in terms of some clinical features associated with COVID-19. We evaluated the expressions of MAP2K4, SNAI1, SLUG, ZEB1 and E-Cadherin. For this purpose, we prospectively recruited 66 individuals, 39 of whom were women and had a mean age of 65 years. The results revealed that MAP2K4 upregulation increased SNAI1 gene expression level whereas E- Cadherin level was decreased in SARS-CoV-2 positive participants. In addition, negative correlations were determined with PLT, Lymphocyte and CKMB and E- Cadherin levels in positive participants. We also observed a negative correlation between the MAP2K4 and AST, and a positive correlation between SLUG and BUN, ZEB1 and CK.

Conclusions: We conclude that SARS-CoV-2 infection triggers fibrosis by increasing MAP2K4 regulation. Additionally, this is the first study to demonstrate the possible contribution of MAP2K4 in influencing COVID-19 clinical features, which may be relevant for identifying COVID-19 positive participants with severe complications.

Alzheimer's disease is a progressive neurodegenerative disorder primarily affecting individuals aged 65 and older, characterized by cognitive decline and diminished quality of life. The molecular hallmarks of AD include extracellular β-amyloid plaques, intracellular neurofibrillary tangles composed of hyperphosphorylated tau protein, and chronic neuroinflammation. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), have emerged as potential therapeutic targets due to their regulatory roles in AD pathogenesis. For example, miR-124 has been shown to modulate Aβ levels, while lncRNAs such as BACE1-AS regulate the expression of BACE1, a crucial enzyme in Aβ production. Transcriptomic studies of AD patients have revealed dysregulation of ncRNA expression, further supporting their involvement in disease progression. This review examines the regulatory functions of ncRNAs in AD, focusing on their impact on Aβ, tau hyperphosphorylation, and neuroinflammation. Additionally, we discuss the emerging role of ncRNAs in liquid-liquid phase separation and the formation of protein aggregates, key processes contributing to AD pathology.

Pancreatic cancer remains as global health challenge, ranking as the seventh leading cause of cancer-related deaths worldwide with high mortality rates and a low five-year survival rate. Despite advancements in conventional therapies, including surgery, chemotherapy, and radiation, the overall survival rates for pancreatic cancer patients have shown minimal improvement. Consequently, there is an urgent need for alternative therapeutic strategies. The search for effective treatments has increasingly turned towards natural products, which offer a diverse array of bioactive compounds with potential anticancer properties. All the natural products, derived from plants, marine organisms, and microorganisms, have emerged as promising candidates in cancer treatment. The review explores the potential role of various natural compounds such as polyphenols, alkaloids, terpenoids, and flavonoids in pancreatic cancer management. With over 60% of cancer medications in clinical trials having natural origins, the review underscores the importance of exploring these compounds for their chemopreventive potential. It covers the epidemiological, molecular pathways influenced by these natural products (such as apoptosis, cell cycle regulation and signaling pathways) and therapeutic aspects aims to contribute to the ongoing efforts in understanding and addressing the complexities of pancreatic cancer. Overall, this review highlights the urgency of developing novel therapeutic strategies and incorporating natural compounds into current treatment modalities to improve outcomes for pancreatic cancer patients.

Background: Wolbachia is an endosymbiont bacterium known to stimulate host immunity against arboviruses and protozoa. Côte d'Ivoire is in a malaria-endemic region, and has experienced several dengue epidemics in recent decades as well. In order to help reduce the transmission of pathogens by mosquito vectors, we studied the prevalence of Wolbachia and the distribution of Cytoplasmic incompatibility factors (Cif) genes in different mosquito species caught in the wild in Cote d'Ivoire.

Methods and results: Mosquitoes of the genera Anopheles, Aedes, Culex, Eretmapodites and Mansonia were captured in five cities. Mosquitoes were collected at larval stage in breeding sites and adults were captured using BG sentinel traps. The mosquitoes were identified morphologically and Wolbachia and Cif were screened using qPCR targeting the 16s rRNA gene and the CifA, B genes. A total of 518 mosquito samples belonging to 15 species and 4 genera were examined. 60% of the species were infected with Wolbachia. The three medically important mosquito species Aedes aegypti, Anopheles gambiae s.l. and Culex quinquefasciatus had a prevalence of 12.84%, 13.46% and 72.64% respectively. The Wolbachia strains infecting the different mosquito species of the genus Culex encoded 98.46% for the CifA gene and 77.69% for the CifB gene.

Conclusion: The presence of Wolbachia and CifA, B genes in mosquitoes of different species in Côte d'Ivoire offer a promising opportunity to reduce the competence of mosquito vectors. Characterization of Wolbachia strains and cytoplasmic incompatibility factors will provide a better understanding of these endosymbionts, enabling the development of vector control strategies.

Background: RAB11 is a small GTP-binding protein that regulates intracellular trafficking of recycling endosomes and is thereby involved in several neural functions. Highly similar RAB11 isoforms are encoded by RAB11A and RAB11B genes, and their pathogenic variants are associated with similar neurodevelopmental disorders, suggesting that RAB11A and RAB11B play similar and important roles in brain development. However, the detailed distribution patterns of these isoforms in various organs, including the brain, remain undetermined.

Methods and results: We generated an antibody against RAB11A and analyzed the distribution of RAB11A and RAB11B in mice. RAB11A was highly expressed in the ovary and the uterus but less abundant in the brain, whereas RAB11B was abundant in the brain, the testis, the ovary, and the uterus. In the developing cortex, RAB11A was enriched in the apical endfeet of apical radial glial cells, whereas RAB11B was abundantly expressed in postmigratory neurons of the cortical plate. In the adult mouse brain, RAB11A and RAB11B were similarly expressed in most neurons, with weak RAB11A signals also observed in the neuropil. In cultured neurons, RAB11A and RAB11B showed only partial co-localization and differential distribution in both soma and neurites. Notably, RAB11A appeared to be more abundant at presynapses than RAB11B.

Conclusions: RAB11A and RAB11B exhibit distinct and characteristic distributions in the brain and other organs, suggesting they play different roles throughout the body. In particular, our results suggest they make distinct contributions to cortical development and regulation of the synaptic vesicle cycle.