Bioinformatics Programs Research Articles

Transposable Element (TE) insertion predictions from RNAseq inputs and TE impact on RNA splicing and gene expression in Drosophila brain transcriptomes

Recent studies have suggested that Transposable Elements (TEs) residing in introns frequently splice into and alter primary gene-coding transcripts. To re-examine the exonization frequency of TEs into protein-coding gene transcripts, we re-analyzed a Drosophila neuron circadian rhythm RNAseq dataset and a deep long RNA fly midbrain RNAseq dataset using our Transposon Insertion and Depletion Analyzer (TIDAL) program. Our TIDAL results were able to predict several TE insertions from RNAseq data that were consistent with previous published studies. However, we also uncovered many discrepancies in TE-exonization calls, such as reads that mainly support intron retention of the TE and little support for chimeric mRNA spliced to the TE. We then deployed rigorous genomic DNA-PCR (gDNA-PCR) and RT-PCR procedures on TE-mRNA fusion candidates to see how many of bioinformatics predictions could be validated. By testing a w1118 strain from which the deeper long RNAseq data was derived and comparing to an OreR strain, only 9 of 23 TIDAL candidates (< 40%) could be validated as a novel TE insertion by gDNA-PCR, indicating that deeper study is needed when using RNAseq data as inputs into current TE-insertion prediction programs. Of these validated calls, our RT-PCR results only supported TE-intron retention. Lastly, in the Dscam2 and Bx genes of the w1118 strain that contained intronic TEs, gene expression was 23 times higher than the OreR genes lacking the TEs. This study's validation approach indicates that chimeric TE-mRNAs are infrequent and cautions that more optimization is required in bioinformatics programs to call TE insertions using RNAseq datasets.

A novel homozygous mutation of CFAP300 identified in a Chinese patient with primary ciliary dyskinesia and infertility.

Primary ciliary dyskinesia (PCD) is a clinically rare, genetically and phenotypically heterogeneous condition characterized by chronic respiratory tract infections, male infertility, tympanitis, and laterality abnormalities. PCD is typically resulted from variants in genes encoding assembly or structural proteins that are indispensable for the movement of motile cilia. Here, we identified a novel nonsense mutation, c.466G>T, in cilia- and flagella-associated protein 300 (CFAP300) resulting in a stop codon (p.Glu156 *) through whole-exome sequencing (WES). The proband had a PCD phenotype with laterality defects and immotile sperm flagella displaying a combined loss of the inner dynein arm (IDA) and outer dynein arm (ODA). Bioinformatic programs predicted that the mutation is deleterious. Successful pregnancy was achieved through intracytoplasmic sperm injection (ICSI). Our results expand the spectrum of CFAP300 variants in PCD and provide reproductive guidance for infertile couples suffering from PCD caused by them.

Comparative genomic analysis of a Colombian strain of Leptospira santarosai serogroup Autumnalis serovar Alice and inference of its virulence factors.

The study aimed to characterize the genome of a Colombian strain of Leptospira santarosai to infer bacterial virulence factors. Under the approach of a quantitative research, an isolate of Colombian origin of L. santarosai was sequenced using new generation 454 GS FLX Titanium sequencers. Subsequently, bioinformatics programs were used for the physical description of the genome (number of genes, size), open reading frame prediction, prediction of proteins and their orthologs in other pathogenic species, of intermediate pathogenicity and non-pathogenic, cellular localization of proteins. The assembly of the spirochete genome was achieved Leptospira santarosai serogroup Autumnalis serovar Aliceand the description of the genetic, structural and functional characteristics of its genes. It is concluded that the core- genome of the isolate is composed of 1747 proteins, which are common to all L. santarosai strains available in GenBank. It was determined that it has a total of 4,138 proteins, 141 of which are unique to its genome. The possible role of the virulence factors found in the Colombian isolate was identified and described. The study contributes to the understanding of the pathophysiological mechanisms induced by Leptospira .

In Silico Analysis of Alzheimer's Disease Mechanism Through DNA Methylation and Gene Expression Data

Alzheimer's Disease (AD) is a debilitating disease impairing memory and thought process with currently no cure. In the current study, GEO2R, an integrated tool in the GEO database, was used to analyze DNA methylation and gene expression datasets associated with AD. Data from the BioGRID Database were used to create a PPI network of differentially methylation and expressed AD genes (DEMEGs). Cytoscape was used to image and analyze the PPI network topologically. The DAVID bioinformatics program was utilized to do enrichment analysis in order to uncover disease associations and signaling pathways. Furthermore, small molecules were predicted using Connectivity Map 2 (Cmap 2) as potential therapeutic agents that might be exploited as pharmacological targets for the study's DEMEGs. As a result, 502 mutual DEMEGs and several hubs that may be researched further as new biomarker candidates for AD such as SMURF1 and UBE2D2 were identified. The link between AD and the MAPK signaling pathway, as well as addiction and brain diseases such as ADHD and epilepsy has been established. Additionally, candidate small molecules that can be used as therapeutics such as flucloxacillin, butamben, and acetohexamide were proposed. This study integrated DNA methylation and gene expression data to further our knowledge of the AD disease mechanism.

Cryptic Diversity of Barred Mudskippers, &lt;i&gt;Periophthalmus argentilineatus&lt;/i&gt; (Valenciennes, 1837), from the Southern Coast of Java and East Lombok, Indonesia inferred by &lt;i&gt;COI&lt;/i&gt; Mitochondrial Gene

The Barred Mudskipper (P. argentilineatus) is an amphibious fish species that displays fully terrestrial behaviour during low tides. Previous studies have indicated the existence of cryptic species of the barred mudskipper, leading to difficulties in taxonomic identification due to similarities in morphological characteristics. Therefore, this study aimed to generate DNA barcodes for Indonesian barred mudskipper populations. We collected ten specimens from Clungup Beach and Kondang Bandung Beach, representing our samples. Additionally, we incorporated 25 previously collected COI sequences from Indonesia into our analysis. The mitochondrial COI gene was amplified using PCR and analysed using various bioinformatics programs. This study provides evidence for the presence of three genetically distinct clades (A, B, and C) within the P. argentilineatus population in Indonesia, with a deep genetic divergence of 2.41% to 6.12%. Clade A showed a high genetic divergence of 5.51-6.12%, suggesting the presence of a cryptic species consistent with previous studies. The high level of haplotype diversity and low nucleotide diversity observed in each clade suggest a population bottleneck followed by a rapid expansion. The lack of geographical separation in the haplotype network analysis indicates that gene flow between populations may have been facilitated by glaciation events in the past. These findings contribute to a better understanding of the biodiversity of the barred mudskipper species in Indonesia and will aid in the accurate identification of cryptic species. This study highlights the importance of using molecular techniques to complement morphological identification in understanding the evolution and diversity of mudskipper fish species.

Identification and functional characteristics of a novel splicing heterozygote variant of COL2A1 associated with Stickler syndrome type I.

Stickler syndrome type I (STL1) is an autosomal dominant disorder characterized by ocular, auditory, orofacial, and skeletal anomalies. The main causes of STL1 are variants in the COL2A1 gene, which encodes a type II collagen precursor protein. The specific focus of this study was on a newborn from China diagnosed with STL1, with the aim of providing novel insights into the effects of a newly identified intronic variant in the COL2A1 gene on pre-mRNA splicing. Trio whole exome sequencing was used to identify the causative variant in the family. The identified variant was validated using Sanger sequencing. Bioinformatics programs were used to predict the pathogenicity of the candidate variant. Additionally, an in vitro minigene assay was used to investigate the effects of the identified variant on RNA splicing. The proband with STL1 had a novel heterozygous splicing variant in the intron nine acceptor donor site of COL2A1 (c.655-2A>G). This splice junction variant resulted in aberrant COL2A1 mRNA splicing, leading to the skipping of exon 10 and the production of a shorter protein that may lack the last 18 native amino acids. The c.655-2A>G variant in the COL2A1 gene leads to STL1 through abnormal splicing. By expanding the spectrum of variants in the COL2A1 gene, this finding improves the clinical understanding of STL1 and provides guidance for early diagnosis and disease counseling.

Establishing African genomics and bioinformatics programs through annual regional workshops.

The African BioGenome Project (AfricaBP) Open Institute for Genomics and Bioinformatics aims to overcome barriers to capacity building through its distributed African regional workshops and prioritizes the exchange of grassroots knowledge and innovation in biodiversity genomics and bioinformatics. In 2023, we implemented 28 workshops on biodiversity genomics and bioinformatics, covering 11 African countries across the 5 African geographical regions. These regional workshops trained 408 African scientists in hands-on molecular biology, genomics and bioinformatics techniques as well as the ethical, legal and social issues associated with acquiring genetic resources. Here, we discuss the implementation of transformative strategies, such as expanding the regional workshop model of AfricaBP to involve multiple countries, institutions and partners, including the proposed creation of an African digital database with sequence information relating to both biodiversity and agriculture. This will ultimately help create a critical mass of skilled genomics and bioinformatics scientists across Africa.

Next-generation bioinformatics: An ultrafast and user-friendly tool for phylogenomic data exploration.

With increasingly large genomic datasets, even routine bioinformatic tasks can be arduous, computationally demanding, and time-consuming. Additionally, most bioinformatic programs do not have a graphical user interface (GUI) and thus, require users to be minimally competent in command-line. These impediments present significant economic and technological barriers for practitioners who do not have access to advanced computational resources and support. In this issue of Molecular Ecology Resources, Handika and Esselstyn (2024) developed an ultrafast and memory-efficient bioinformatic tool, SEGUL, that performs common manipulations and calculations of summary statistics on phylogenomic datasets. SEGUL has two main features that distinguish it from other bioinformatic programs: (1) it is based on the recently emergent, high-performance programming language Rust, and (2) it has a GUI written using Flutter, a cross-platform programming framework that also supports mobile operating systems (mobile iOS, iPadOS and Android). By leveraging and combining the power of Rust and Flutter, SEGUL achieves significantly faster computation times and lower memory usage across different platforms and CPU architectures compared to similar programs. The unique and innovative features of SEGUL pave the way for a new era of bioinformatics that can be more energy-efficient, inclusive, and available to a broader swathe of users.

Upregulation of LncRNA UCA1 promotes cardiomyocyte proliferation by inhibiting the miR-128/SUZ12/P27 pathway

Enhancing cardiomyocyte proliferation is essential to reverse or slow down the heart failure progression in many cardiovascular diseases such as myocardial infarction (MI). Long non-coding RNAs (lncRNAs) have been reported to regulate cardiomyocyte proliferation. In particular, lncRNA urothelial carcinoma-associated 1 (lncUCA1) played multiple roles in regulating cell cycle progression and cardiovascular diseases, making lncUCA1 a potential target for promoting cardiomyocyte proliferation. However, the role of lncUCA1 in cardiomyocyte proliferation remains unknown. This study aimed at exploring the function and underlying molecular mechanism of lncUCA1 in cardiomyocyte proliferation. Quantitative RT-PCR showed that lncUCA1 expression decreased in postnatal hearts. Gain-and-loss-of-function experiments showed that lncUCA1 positively regulated cardiomyocyte proliferation in vitro and in vivo. The bioinformatics program identified miR-128 as a potential target of lncUCA1, and loss of miR-128 was reported to promote cardiomyocyte proliferation by inhibiting the SUZ12/P27 pathway. Luciferase reporter assay, qRT-PCR, western blotting, and immunostaining experiments further revealed that lncUCA1 acted as a ceRNA of miR-128 to upregulate its target SUZ12 and downregulate P27, thereby increasing cyclin B1, cyclin E, CDK1 and CDK2 expression to promote cardiomyocyte proliferation. In conclusion, upregulation of lncRNA UCA1 promoted cardiomyocyte proliferation by inhibiting the miR-128/SUZ12/P27 pathway. Our results indicated that lncUCA1 might be a new therapeutic target for stimulating cardiomyocyte proliferation.

Bioinformatics and biomedical informatics with ChatGPT: Year one review.

The year 2023 marked a significant surge in the exploration of applying large language model chatbots, notably Chat Generative Pre-trained Transformer (ChatGPT), across various disciplines. We surveyed the application of ChatGPT in bioinformatics and biomedical informatics throughout the year, covering omics, genetics, biomedical text mining, drug discovery, biomedical image understanding, bioinformatics programming, and bioinformatics education. Our survey delineates the current strengths and limitations of this chatbot in bioinformatics and offers insights into potential avenues for future developments.

In Silico Structural Modeling and Analysis of Physicochemical Properties of Antitumoral QS‐13 Peptide and Its Derivatives in Water and Dimethyl Sulfoxide

ABSTRACTThe NC1 domain of the alpha 4 chain of type IV collagen was previously reported to exert anti‐tumor properties in a melanoma model and to inhibit angiogenesis. The minimal active sequence identified to date comprises 13 amino acids: QKISRCQVCVKYS. Unfortunately, this sequence is not soluble in aqueous media and requires prior dissolution in DMSO. The disulfide bridge (DB) that spontaneously forms in solution between two cysteine residues is crucial for its biological activity. The aim of this article was to study the impact of DMSO on the physicochemical properties of the QS‐13 peptide and to replace hydrophobic amino acids to enhance its water solubility. Using bioinformatics (GROMACS, VMD, and ProtParam) and programming (Python and RStudio) software programs, we demonstrated that DMSO could promote the formation of DBs, but it is not strictly necessary. Among the QS‐13 substituted peptides, some were demonstrated to display similar characteristics to the original peptide. Improved water solubility will make the peptide easier to use in biological studies and facilitate its administration for potential therapeutic applications.

Identification of seven variants in the col4a1 gene that alter RNA splicing by minigene assay.

Type IV collagen is an integral component of basement membranes. Mutations in COL4A1, one of the key genes encoding Type IV collagen, can result in a variety of diseases. It is clear that a significant proportion of mutations that affect splicing can cause disease directly or contribute to the susceptibility or severity of disease. Here, we analyzed exonic mutations and intronic mutations described in the COL4A1 gene using bioinformatics programs and identified candidate mutations that may alter the normal splicing pattern through a minigene system. We identified seven variants that induce splicing alterations by disrupting normal splice sites, creating new ones, or altering splice regulatory elements. These mutations are predicted to impact protein function. Our results help in the correct molecular characterization of variants in COL4A1 and may help develop more personalized treatment options.

MicroRNA-451 Regulates Angiogenesis in Intracerebral Hemorrhage by Targeting Macrophage Migration Inhibitory Factor.

Intracerebral hemorrhage (ICH) is a subtype of stroke with the highest fatality and disability rate. Up to now, commonly used first-line therapies have limited value in improving prognosis. Angiogenesis is essential to neurological recovery after ICH. Recent studies have shown that microRNA-451(miR-451) plays an important role in angiogenesis by regulating the function of vascular endothelial cells. We found miR-451 was significantly decreased in the peripheral blood of ICH patients in the acute stage. Based on the clinical findings, we conducted this study to investigate the potential regulatory effect of miR-451 on angiogenesis after ICH. The expression of miR-451 in ICH mouse model and in a hemin toxicity model of human brain microvascular endothelial cells (hBMECs) was decreased the same as in ICH patients. MiR-451 negatively regulated the proliferation, migration, and tube formation of hBMECs in vitro. MiR-451 negatively regulated the microvessel density in the perihematoma tissue and affected neural functional recovery of ICH mouse model. Knockdown of miR-451 could recovered tight junction and protect the integrity of blood-brain barrier after ICH. Based on bioinformatic programs, macrophage migration inhibitory factor (MIF) was predicted to be the target gene and identified to be regulated by miR-451 inhibiting the protein translation. And p-AKT and p-ERK were verified to be downstream of MIF in angiogenesis. These results all suggest that miR-451 will be a potential target for regulating angiogenesis in ICH.

Mitochondrial DNA control of gene expression and cell function in HeLa cybrids of HeLa ρ0 cells with transferred mtDNA of A549 cells

Asthma is a disease characterized by airway inflammation and hyperreactivity. Mitochondria have their own DNA (mtDNA) that encodes essential components of Electron Transport Chain complexes and is inherited exclusively maternally. Variants in mtDNA (haplogroups) are linked to risks and severity of other diseases but have not been studied in asthma. We hypothesized that mitochondrial genome can regulate expression of nDNA genes important in asthma pathophysiology. Haplogroup H mtDNA from A549 lung epithelial cells was transferred to mtDNA-deleted HeLa cells (ρ0) to create HeLa[H] cybrids that have identical nuclei but varied mitochondrial genome as compared to HeLa cells with haplogroup L mtDNA. Cells were analyzed for mtDNA copy number by quantitative polymerase chain reaction (qPCR), energy metabolism by monitoring the cellular respiration and glycolysis using Seahorse analyzer, and mtDNA sequencing for haplogroup. Single-cell RNA sequencing technology, SeqGeq bioinformatics program, and western blot were used to analyze differential gene expression and involved pathways among these cells. ρ0 cells have mtDNA copy number &lt;1, while cybrids have mtDNA copy number similar to A549 cells and different from HeLa cells {mtDNA copy number (mean±SD), HeLa 636±115, ρ0 0.13±0.08, cybrid 1956±354, A549 1738±504, n≥2 replicate experiments, ANOVA p&lt;0.001}. ρ0 have no mitochondrial oxygen consumption and maintain energy generation by increased glycolysis, whereas cybrids have similar oxygen consumption and glycolytic rates to HeLa and A549 {mitochondrial basal oxygen consumption pmole/min/mg protein (mean±SD), HeLa 7.78±0.43, ρ0 0.51±0.56, cybrid 6.76±2.34, A549 4.86±0.41, n≥3, ANOVA p&lt;0.001; glycolysis mpH/min/mg protein (mean±SD), HeLa 0.91±0.08, ρ0 1.96±0.16, cybrid 0.52±0.14, A549 0.72±0.48, n≥3, ANOVA p&lt;0.001}. Compared to HeLa, ρ0 cells lack expression of all 13 mtDNA-encoded proteins and have changes in nuclear-encoded DNA (nDNA) gene expression (4,047 nDNA up, and 5,552 nDNA down). Switching from L to H haplogroup results in greater changes in gene expression (9,320 nDNA up, 4,376 nDNA down, 9 mtDNA up, and 4 mtDNA down). Compared to HeLa, cybrids have greater expression of genes important in bioenergetics and asthma, i.e., TCA pathway genes (aconitase, isocitrate dehydrogenase, oxoglutarate dehydrogenase, succinate dehydrogenase), cytokines, and inducible NO synthase (iNOS) pathway genes. Overall, these studies suggest that mitochondria are not only important for energy generation but relevant to cell signaling, inflammation, and metabolism in asthma. This work is supported by the National Heart, Lung, and Blood Institute HL081064, HL103453. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Abstract 1585: Tenascin C in pancreatic cancer-associated fibroblasts enhances epithelial mesenchymal transition and is associated with resistance to immune checkpoint inhibitor

Abstract Backgrounds: Tenascin C (TNC) is an extracellular matrix glycoprotein that is abundantly expressed in cancer stroma and its overexpression correlates with tumor progression in various types of cancer including pancreatic adenocarcinoma (PAAD). However, the role of TNC in regards to response to immune checkpoint inhibitor (ICI) still remains to be identified. In this study, we aimed to investigate the potential involvement of TNC in the response to ICI among PAAD patients. Materials and Methods: Transcriptomic profiles were downloaded by TCGA and GTEx database and TNC mRNA levels were compared between tumors and normal tissues. These transcriptomic data were deconvoluted using CIBERSORTx to identify specific enriched pathways in cancer cells and cancer-associated fibroblasts (CAFs) in PAAD patients. Bioinformatic programs were used to predict paracrine communications between cancer cells and cancer-associated fibroblasts (CAFs), and the Tumor Immune Dysfunction and Exclusion (TIDE) score was calculated to predict response to ICI treatment in PAAD patients. An independent immunotherapeutic cohort was applied to validate prediction values for immunotherapy. Results: TNC mRNA levels were significantly upregulated in tumors compared to normal tissues in eight cancer types including PAAD. TNC-high (TNC-H) PAAD patients (n = 138) had significant shorter overall survival than TNC-low (TNC-L) patients (n = 40) (p = 0.0125, Log-rank test). Using CIBERSORTx, TNC was estimated to be predominantly expressed in CAFs in PAAD. In pathway analysis, both cancer cells and CAFs had significant enrichments of the epithelial mesenchymal transition pathway in TNC-H patients. Ligand-receptor interaction analysis showed that TNC produced in CAFs had the highest interaction potentials to bind to integrin families such as ITGαV and ITGβ3 in cancer cells. In an independent immunotherapy data cohort, patients with TNC-H and ITGαV-high or ITGβ3-high expression were associated with poor response to ICI treatment and had shorter overall survival than those with both low expressions. Conclusions: In conclusion, these findings suggest that TNC-high CAFs can play a crucial role in tumor progression and resistance to ICI therapy in PAAD patients, and targeting TNC and its interactions with cancer cells may provide a potential strategy for improving the efficacy of ICI therapy in PAAD. Citation Format: Satoru Furuhashi, Yoshifumi Morita, Akio Matsumoto, Shinya Ida, Ryuta Muraki, Ryo Kitajima, Makoto Takeda, Hirotoshi Kikuchi, Yoshihiro Hiramatsu, Hiroya Takeuchi. Tenascin C in pancreatic cancer-associated fibroblasts enhances epithelial mesenchymal transition and is associated with resistance to immune checkpoint inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1585.

The pathogenic mutations of APOA5 in Chinese patients with hyperlipidemic acute pancreatitis

Background and aimsTo study the role of gene mutations in the development of severe hypertriglyceridemia (HTG) in patients with hyperlipidemic acute pancreatitis (HLAP), especially different apolipoprotein A5 (APOA5) mutations.MethodsWhole-exome sequencing was performed on 163 patients with HLAP and 30 patients with biliary acute pancreatitis (BAP). The pathogenicity of mutations was then assessed by combining clinical information, predictions of bioinformatics programs, information from multiple gene databases, and residue location and conservation. The pathogenic mutations of APOA5 were visualized using the software.Results1. Compared with BAP patients, pathogenic mutations of APOA5 were frequent in HLAP patients; among them, the heterozygous mutation of p.G185C was the most common.2. All six pathogenic mutations of APOA5 identified in this study (p.S35N, p.D167V, p.G185C, p.K188I, p.R223C, and p.H182fs) were positively correlated with severe HTG; they were all in the important domains of apolipoprotein A-V (apoA-V). Residue 223 is strictly conserved in multiple mammals and is located in the lipoprotein lipase (LPL)-binding domain (Pro215–Phe261). When Arg 223 is mutated to Cys 223, the positive charge of this residue is reduced, which is potentially destructive to the binding function of apoA-V to LPL.3. Four new APOA5 mutations were identified, namely c.563A > T, c.667C > T, c.788G > A, and c.544_545 insGGTGC.ConclusionsThe pathogenic mutations of APOA5 were specific to the patients with HLAP and severe HTG in China, and identifying such mutations had clinical significance in elucidating the etiology and subsequent treatment.Graphical

Three exonic variants in the COL4A5 gene alter RNA splicing in a minigene assay.

X-linked Alport syndrome (XLAS) is an inherited renal disease caused by rare variants of COL4A5 on chromosome Xq22. Many studies have indicated that single nucleotide variants (SNVs) in exons can disrupt normal splicing process of the pre-mRNA by altering various splicing regulatory signals. The male patients with XLAS have a strong genotype-phenotype correlation. Confirming the effect of variants on splicing can help to predict kidney prognosis. This study aimed to investigate whether single nucleotide substitutions, located within three bases at the 5' end of the exons or internal position of the exons in COL4A5 gene, cause aberrant splicing process. We analyzed 401 SNVs previously presumed missense and nonsense variants in COL4A5 gene by bioinformatics programs and identified candidate variants that may affect the splicing of pre-mRNA via minigene assays. Our study indicated three of eight candidate variants induced complete or partial exon skipping. Variants c.2678G>C and c.2918G>A probably disturb classic splice sites leading to corresponding exon skipping. Variant c.3700C>T may disrupt splicing enhancer motifs accompanying with generation of splicing silencer sequences resulting in the skipping of exon 41. Our study revealed that two missense variants positioned the first nucleotides of the 5' end of COL4A5 exons and one internal exonic nonsense variant caused aberrant splicing. Importantly, this study emphasized the necessity of assessing the effects of SNVs at the mRNA level.

A Tool to Teach Evolution of Protein Sequences and Structures

Computer modeling and protein structure visualization tools are effective and engaging ways of presenting various molecular biology concepts to high school and college students. Here, we describe a series of activities and exercises that use online bioinformatics databases and programs to search for and obtain protein sequence and structure data and use it to build homology models of proteins. Exercises in homology modeling can serve the pedagogical purpose of introducing and illustrating the concept of homology within gene and protein families, which results in conservation of the 3D structures of proteins and allows us to predict structures when experimental data are not available.

Selenium affects genes associated with immunity and apoptosis in in vitro follicles of ewes

Selenium plays an important role in bodily functions. It activates immune cells such as neutrophils and immunity through T cells. However, its role in ovarian follicular gene expression has not been reported. The effects of selenomethionine (SeMet) on gene expression in in vitro ewe follicles and their relationship with immunity and apoptosis were studied. Preovulatory follicles were randomly cultured, and SeMet was added to the culture, followed by incubation for 24 h. Total RNA was extracted from follicles and placed on a microarray chip. Gene expression was analyzed using GenArise and classified using the DAVID v6.8 bioinformatics program based on the Gene Ontology and Kyoto Encyclopedia for Genes and Genomes (KEGG). Gene pathways were designed using Cytoscape v3.7.2. There were 2,538 differentially expressed genes (DEGs): 1,228 upregulated and 1,310 downregulated. The upregulated genes were classified into 32, 18, and 12 nodes related to biological processes, cellular components, and molecular functions, respectively. KEGG assigned these genes to 41 metabolic and signaling pathways. 94 genes were involved in eight pathways associated with immune processes. The expression levels of CD8, NFAT2, and CD48 were quantified using RT-qPCR. Selenium activated gene expression in the in vitro preovulatory follicles of ewes, some of which were related to the immune system. The relationship among CD8, NFAT2, and CD48 genes suggests a possible immune pathway related to follicular apoptosis regulation.

Genotypic Identification of Endodontic Bacteria Isolated from Berhampur, Odisha, India: First Insights

ABSTRACT Background: Endodontic infections caused by many bacterial species including Staphylococcus aureus, Klebsiella pneumonia and Salmonella enterica present a significant challenge in dental health. Accurate identification of these pathogens is crucial for effective treatment strategies. Aims and Objectives: The aim of the study was to utilize 16S rRNA genotypic analysis for the precise identification of certain bacterial strains isolated from endodontic infected tissues. Materials and Methods: Tissue samples were collected from patients with persistent endodontic infections and microbial cultures were prepared. Strains were isolated, purified. DNA extraction was performed and 16S rRNA gene amplification was carried out using polymerase chain reaction. Subsequently, the amplicons were sequenced and the sequences were compared with known reference sequences using bioinformatics programs. Phylogenetic analysis was conducted to ascertain the evolutionary relationships between the identified isolates and known strains. Results: To our knowledge, this is the first report focusing on genotypic identification of endodontic bacteria from Berhampur, Odisha, India. This study holds implications for species specific microbial ecology in dental infections facilitating quicker identification. Conclusion: Management strategies for endodontic infections may involve a systematic approach to identify, analyze and address the specific challenges such as diagnosis and endodontic emergencies, presented by each case. Focused and individualized treatment plans shall contribute to better clinical outcomes. Further detailed records can be maintained with genotype based treatment plan followed by post treatment outcomes to guide future decisions and research.