Displaying publications 1 - 20 of 379 in total

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  1. Toh C, Mohd-Hairul AR, Ain NM, Namasivayam P, Go R, Abdullah NAP, et al.
    BMC Res Notes, 2017 Nov 02;10(1):554.
    PMID: 29096695 DOI: 10.1186/s13104-017-2872-6
    BACKGROUND: Vanda Mimi Palmer (VMP) is commercially valuable for its strong fragrance but little is known regarding the fragrance production and emission sites on the flowers.

    RESULTS: Olfactory perception detected fragrance only from the petals and sepals. Light and Environmental Scanning Electron microscopy analyses on fresh tissues showed distributions of stomata and trichomes concentrated mostly around the edges. These results paralleled the rich starch deposits and intense neutral red stain, indicating strong fragrance and trichomes as potential main fragrance release sites. Next Generation Sequencing (NGS) transcriptomic data of adaxial and abaxial layers of the tissues showed monoterpene synthase transcripts specifically linalool and ocimene synthases distributed throughout the tissues. qPCR analyses taken at different time points revealed high levels of linalool and ocimene synthases transcripts in the early morning with maximal level at 4.00 am but remained low throughout daylight hours.

    CONCLUSIONS: Knowledge of the VMP floral anatomy and its fragrance production characteristics, which complemented our previous molecular and biochemical data on VMP, provided additional knowledge on how fragrance and flower morphology are closely intertwined. Further investigation on the mechanisms of fragrance biosynthesis and interaction of potential pollinators would elucidate the evolution of the flower morphology to maximize the reproduction success of this plant.

    Matched MeSH terms: Gene Expression Profiling/methods*
  2. Li N, Tian W, Sun L, Yan H, Hasi S
    Trop Biomed, 2024 Sep 01;41(3):290-297.
    PMID: 39548783 DOI: 10.47665/tb.41.3.009
    This study explored the transcriptome differences in Fasciola hepatica at different developmental stages and identified functional genes related to growth and development during juvenile stages. DNBSEQ eukaryotic strand-specific transcriptome resequencing technology was used to sequence the transcriptomes of Fasciola hepatica eggs, juveniles, and adults. Additionally, the genes that were highly expressed during the juvenile stage were validated using qRT-PCR. The Q20 values of all three phases of sequencing were above 98%, and the Q30 values were above 94%. The differentially expressed genes (DEGs) in pairwise comparisons were analyzed by GO functional classification and the KEGG pathway database. Many immune-, growth-, and development-related pathways were found, which might be related to cell proliferation, development, and host immune evasion by Fasciola hepatica. In addition, five DEGs with high expression levels during the juvenile stage were identified: Cathepsin B, Glutathione S-transferase mu, heat shock protein 67B2, Kunitz-CH, and Legumain. Validation analyses revealed that these genes play key roles in maintaining normal growth, development, and immunological processes in liver Fasciola hepatica. RNA-seq was used to analyze the biological characteristics of the DEGs at different developmental stages concerning GO functional classification and KEGG metabolic pathways. Five DEGs with high expression during the juvenile stage were identified. These genes are related to the growth, development, and immune function of Fasciola hepatica, which provides a theoretical basis for subsequent research on the proteomics of Fasciola hepatica and the screening of candidate genes for early diagnosis.
    Matched MeSH terms: Gene Expression Profiling
  3. Liu X, Gao J, Zhang P, Shi T, Yan B, Azra MN, et al.
    Genomics, 2023 Nov;115(6):110746.
    PMID: 37977333 DOI: 10.1016/j.ygeno.2023.110746
    To study the mechanism of the biomolecular response in Exopalaemon carinicauda to starvation stress, we subjected muscle tissue RNA samples from four stress points, including 0 d(control group), 10 d, 20 d, and 30 d, to starvation stress on white ridgetail prawn with a body weight of 1.41 + 0.42 g, aquaculture water temperature of 23-25 °C, salinity of 26, dissolved oxygen ≥5 mg/L, and pH 8-8.5, Then performed de novo transcriptome assembly and gene expression analysis using BGISEQ-500 with a tag-based digital gene expression (DGE) system. By de novo assembling at the four times, we obtained 28,167, 21,115, 24,497, and 27,080 reads, respectively. The results showed that the stress at 10 d led to no significant difference in the expressed genes, while the stress at 20 d and 30 d showed a significant increase (or decrease) in the expression of 97 (276) and 143 (410) genes, respectively, which were involved in 8 different metabolic pathways. In addition, we detected 2647 unigene transcription factors. Eleven upregulated and sixteen downregulated genes from the different starvation stress groups were choose to verify the reliability of the transcriptome data, and the results showed that the expression trends of these genes were consistent with the results shown by the transcriptome. The analysis of the experimental data and our discussion of the response mechanism of white ridgetail prawn under starvation stress provides a foundation for further screening of the key genes of starvation stress and may help to elucidate their functions.
    Matched MeSH terms: Gene Expression Profiling*
  4. Aizat WM, Ismail I, Noor NM
    Adv Exp Med Biol, 2018 11 2;1102:1-9.
    PMID: 30382565 DOI: 10.1007/978-3-319-98758-3_1
    The central dogma of molecular biology (DNA, RNA, protein and metabolite) has engraved our understanding of genetics in all living organisms. While the concept has been embraced for many decades, the development of high-throughput technologies particularly omics (genomics, transcriptomics, proteomics and metabolomics) has revolutionised the field to incorporate big data analysis including bioinformatics and systems biology as well as synthetic biology area. These omics approaches as well as systems and synthetic biology areas are now increasingly popular as seen by the growing numbers of publication throughout the years. Several journals which have published most of these related fields are also listed in this chapter to overview their impact and target journals.
    Matched MeSH terms: Gene Expression Profiling/trends*
  5. Jumat MI, Chin KL
    World J Microbiol Biotechnol, 2024 Jul 25;40(9):279.
    PMID: 39048776 DOI: 10.1007/s11274-024-04089-6
    Mycobacterium tuberculosis (Mtb), the tuberculosis-causing agent, exhibits diverse genetic lineages, with known links to virulence. While genomic and transcriptomic variations between modern and ancient Mtb lineages have been explored, the role of small non-coding RNA (sRNA) in post-translational gene regulation remains largely uncharted. In this study, Mtb Lineage 1 (L1) Sabahan strains (n = 3) underwent sRNA sequencing, revealing 351 sRNAs, including 23 known sRNAs and 328 novel ones identified using ANNOgesic. Thirteen sRNAs were selected based on the best average cut-off value of 300, with RT-qPCR revealing significant expression differences for sRNA 1 (p = 0.0132) and sRNA 29 (p = 0.0012) between Mtb L1 and other lineages (L2 and L4, n = 3) (p > 0.05). Further characterization using RACE (rapid amplification of cDNA ends), followed by target prediction with TargetRNA3 unveils that sRNA 1 (55 base pairs) targets Rv0506, Rv0697, and Rv3590c, and sRNA 29 (86 base pairs) targets Rv33859c, Rv3345c, Rv0755c, Rv0107c, Rv1817, Rv2950c, Rv1181, Rv3610c, and Rv3296. Functional characterization with Mycobrowser reveals these targets involved in regulating intermediary metabolism and respiration, cell wall and cell processes, lipid metabolism, information pathways, and PE/PPE. In summary, two novel sRNAs, sRNA 1 and sRNA 29, exhibited differential expression between L1 and other lineages, with predicted roles in essential Mtb functions. These findings offer insights into Mtb regulatory mechanisms, holding promise for the development of improved tuberculosis treatment strategies in the future.
    Matched MeSH terms: Gene Expression Profiling*
  6. Pendi FH, Hussain H
    BMC Res Notes, 2024 Sep 05;17(1):251.
    PMID: 39238033 DOI: 10.1186/s13104-024-06924-3
    OBJECTIVE: Sago palm (Metroxylon sagu Rottb.) is one of the most important economic crops abundantly found in Mukah, Sarawak, Malaysia. The robustness of the palm triggered the Sarawak government's selection as one of the state's commodity crops, with the opening of several sago palm plantations. However, stunted (non-trunking) palms were reported in several sago palm plantations despite attaining a maturity period of more than ten years after cultivation. Research targeting this problem has been conducted in various fields, yet information on molecular mechanisms is still scarce. This study aimed to determine the genes responsible for sago palm's normal phenotype (trunking) by attaining leaf transcriptomes from samples of all trunking sago palms from different sago palm plantations.

    DATA DESCRIPTION: The conventional CTAB method was employed in the present investigation to extract total RNA from leaf tissues. Transcriptome sequencing was conducted on the Illumina NovaSeq 6000 platform. Differential expression analysis was performed using the DESeq2 package. A total of 6,119 differentially expressed genes, comprising 4,384 downregulated and 1,735 upregulated genes, were expressed in all three sago palm datasets. The datasets provide insights into the commonly expressed genes among trunking sago palms.

    Matched MeSH terms: Gene Expression Profiling/methods
  7. Tan MS, Tan JW, Chang SW, Yap HJ, Abdul Kareem S, Zain RB
    PeerJ, 2016;4:e2482.
    PMID: 27688975 DOI: 10.7717/peerj.2482
    The potential of genetic programming (GP) on various fields has been attained in recent years. In bio-medical field, many researches in GP are focused on the recognition of cancerous cells and also on gene expression profiling data. In this research, the aim is to study the performance of GP on the survival prediction of a small sample size of oral cancer prognosis dataset, which is the first study in the field of oral cancer prognosis.
    Matched MeSH terms: Gene Expression Profiling
  8. Prabhakaran P, Nazir MYM, Thananusak R, Hamid AA, Vongsangnak W, Song Y
    PMID: 37625782 DOI: 10.1016/j.bbalip.2023.159381
    Aurantiochytrium sp., a marine thraustochytrid possesses a remarkable ability to produce lipid rich in polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA). Although gene regulation underlying lipid biosynthesis has been previously reported, proteomic analysis is still limited. In this study, high DHA accumulating strain Aurantiochytrium sp. SW1 has been used as a study model to elucidate the alteration in proteome profile under different cultivation phases i.e. growth, nitrogen-limitation and lipid accumulation. Of the total of 5146 identified proteins, 852 proteins were differentially expressed proteins (DEPs). The largest number of DEPs (488 proteins) was found to be uniquely expressed between lipid accumulating phase and growth phase. Interestingly, there were up-regulated proteins involved in glycolysis, glycerolipid, carotenoid and glutathione metabolism which were preferable metabolic routes towards lipid accumulation and DHA production as well as cellular oxidative defence. Integrated proteomic and transcriptomic data were also conducted to comprehend the gene and protein regulation underlying the lipid and DHA biosynthesis. A significant up-regulation of acetyl-CoA synthetase was observed which suggests alternative route of acetate metabolism for acetyl-CoA producer. This study presents the holistic routes underlying lipid accumulation and DHA production in Aurantiochytrium sp. SW1 and other relevant thraustochytrid.
    Matched MeSH terms: Gene Expression Profiling
  9. Mohandas S, Shete A, Sarkale P, Kumar A, Mote C, Yadav P
    Virulence, 2023 Dec;14(1):2224642.
    PMID: 37312405 DOI: 10.1080/21505594.2023.2224642
    Nipah virus (NiV) is a high-risk pathogen which can cause fatal infections in humans. The Indian isolate from the 2018 outbreak in the Kerala state of India showed ~ 4% nucleotide and amino acid difference in comparison to the Bangladesh strains of NiV and the substitutions observed were mostly not present in the region of any functional significance except for the phosphoprotein gene. The differential expression of viral genes was observed following infection in Vero (ATCC® CCL-81™) and BHK-21 cells. Intraperitoneal infection in the 10-12-week-old, Syrian hamster model induced dose dependant multisystemic disease characterized by prominent vascular lesions in lungs, brain, kidney and extra vascular lesions in brain and lungs. Congestion, haemorrhages, inflammatory cell infiltration, thrombosis and rarely endothelial syncitial cell formation were seen in the blood vessels. Intranasal infection resulted in respiratory tract infection characterised by pneumonia. The model showed disease characteristics resembling the human NiV infection except that of myocarditis similar to that reported by NiV-Malaysia and NiV-Bangladesh isolates in hamster model. The variation observed in the genome of the Indian isolate at the amino acid levels should be explored further for any functional significance.
    Matched MeSH terms: Gene Expression Profiling
  10. Suhaimi AH, Kobayashi MJ, Satake A, Ng CC, Lee SL, Muhammad N, et al.
    PeerJ, 2023;11:e16368.
    PMID: 38047035 DOI: 10.7717/peerj.16368
    Climatic factors have commonly been attributed as the trigger of general flowering, a unique community-level mass flowering phenomenon involving most dipterocarp species that forms the foundation of Southeast Asian tropical rainforests. This intriguing flowering event is often succeeded by mast fruiting, which provides a temporary yet substantial burst of food resources for animals, particularly frugivores. However, the physiological mechanism that triggers general flowering, particularly in dipterocarp species, is not well understood largely due to its irregular and unpredictable occurrences in the tall and dense forests. To shed light on this mechanism, we employed ecological transcriptomic analyses on an RNA-seq dataset of a general flowering species, Shorea curtisii (Dipterocarpaceae), sequenced from leaves and buds collected at multiple vegetative and flowering phenological stages. We assembled 64,219 unigenes from the transcriptome of which 1,730 and 3,559 were differentially expressed in the leaf and the bud, respectively. Differentially expressed unigene clusters were found to be enriched with homologs of Arabidopsis thaliana genes associated with response to biotic and abiotic stresses, nutrient level, and hormonal treatments. When combined with rainfall data, our transcriptome data reveals that the trees were responding to a brief period of drought prior to the elevated expression of key floral promoters and followed by differential expression of unigenes that indicates physiological changes associated with the transition from vegetative to reproductive stages. Our study is timely for a representative general flowering dipterocarp species that occurs in forests that are under the constant threat of deforestation and climate change as it pinpoints important climate sensitive and flowering-related homologs and offers a glimpse into the cascade of gene expression before and after the onset of floral initiation.
    Matched MeSH terms: Gene Expression Profiling
  11. Sultan G, Zubair S
    Comput Biol Chem, 2024 Feb;108:107999.
    PMID: 38070457 DOI: 10.1016/j.compbiolchem.2023.107999
    Breast cancer continues to be a prominent cause for substantial loss of life among women globally. Despite established treatment approaches, the rising prevalence of breast cancer is a concerning trend regardless of geographical location. This highlights the need to identify common key genes and explore their biological significance across diverse populations. Our research centered on establishing a correlation between common key genes identified in breast cancer patients. While previous studies have reported many of the genes independently, our study delved into the unexplored realm of their mutual interactions, that may establish a foundational network contributing to breast cancer development. Machine learning algorithms were employed for sample classification and key gene selection. The best performance model further selected the candidate genes through expression pattern recognition. Subsequently, the genes common in all the breast cancer patients from India, China, Czech Republic, Germany, Malaysia and Saudi Arabia were selected for further study. We found that among ten classifiers, Catboost exhibited superior performance with an average accuracy of 92%. Functional enrichment analysis and pathway analysis revealed that calcium signaling pathway, regulation of actin cytoskeleton pathway and other cancer-associated pathways were highly enriched with our identified genes. Notably, we observed that these genes regulate each other, forming a complex network. Additionally, we identified PALMD gene as a novel potential biomarker for breast cancer progression. Our study revealed key gene modules forming a complex network that were consistently expressed in different populations, affirming their critical role and biological significance in breast cancer. The identified genes hold promise as prospective biomarkers of breast cancer prognosis irrespective of country of origin or ethnicity. Future investigations will expand upon these genes in a larger population and validate their biological functions through in vivo analysis.
    Matched MeSH terms: Gene Expression Profiling
  12. Zamani S, Salehi M, Ehterami A, Fauzi MB, Abbaszadeh-Goudarzi G
    J Biomater Appl, 2024 Apr;38(9):957-974.
    PMID: 38453252 DOI: 10.1177/08853282241238581
    Skin tissue engineering has gained significant attention as a promising alternative to traditional treatments for skin injuries. In this study, we developed 3D hydrogel-based scaffolds, Alginate, incorporating different concentrations of Curcumin and evaluated their properties, including morphology, swelling behavior, weight loss, as well as hemo- and cytocompatibility. Furthermore, we investigated the therapeutic potential of Alginate hydrogel containing different amounts of Curcumin using an in vitro wound healing model. The prepared hydrogels exhibited remarkable characteristics, SEM showed that the pore size of hydrogels was 134.64 μm with interconnected pores, making it conducive for cellular infiltration and nutrient exchange. Moreover, hydrogels demonstrated excellent biodegradability, losing 63.5% of its weight over 14 days. In addition, the prepared hydrogels had a stable release of curcumin for 3 days. The results also show the hemocompatibility of prepared hydrogels and a low amount of blood clotting. To assess the efficacy of the developed hydrogels, 3T3 fibroblast growth was examined during various incubation times. The results indicated that the inclusion of Curcumin at a concentration of 0.1 mg/mL positively influenced cellular behavior. The animal study showed that Alginate hydrogel containing 0.1 mg/mL curcumin had high wound closure(more than 80%) after 14 days. In addition, it showed up-regulation of essential wound healing genes, including TGFβ1 and VEGF, promoting tissue repair and angiogenesis. Furthermore, the treated group exhibited down-regulation of MMP9 gene expression, indicating a reduction in matrix degradation and inflammation. The observed cellular responses and gene expression changes substantiate the therapeutic efficacy of prepared hydrogels. Consequently, our study showed the healing effect of alginate-based hydrogel containing Curcumin on skin injuries.
    Matched MeSH terms: Gene Expression Profiling
  13. Nagappan J, Ooi SE, Chan KL, Kadri F, Nurazah Z, Halim MAA, et al.
    Mol Biol Rep, 2024 Jan 25;51(1):212.
    PMID: 38273212 DOI: 10.1007/s11033-023-09054-4
    BACKGROUND: Ganoderma boninense is a phytopathogen of oil palm, causing basal and upper stem rot diseases.

    METHODS: The genome sequence was used as a reference to study gene expression during growth in a starved carbon (C) and nitrogen (N) environment with minimal sugar and sawdust as initial energy sources. This study was conducted to mimic possible limitations of the C-N nutrient sources during the growth of G. boninense in oil palm plantations.

    RESULTS: Genome sequencing of an isolate collected from a palm tree in West Malaysia generated an assembly of 67.12 Mb encoding 19,851 predicted genes. Transcriptomic analysis from a time course experiment during growth in this starvation media identified differentially expressed genes (DEGs) that were found to be associated with 29 metabolic pathways. During the active growth phase, 26 DEGs were related to four pathways, including secondary metabolite biosynthesis, carbohydrate metabolism, glycan metabolism and mycotoxin biosynthesis. G. boninense genes involved in the carbohydrate metabolism pathway that contribute to the degradation of plant cell walls were up-regulated. Interestingly, several genes associated with the mycotoxin biosynthesis pathway were identified as playing a possible role in pathogen-host interaction. In addition, metabolomics analysis revealed six metabolites, maltose, xylobiose, glucooligosaccharide, glycylproline, dimethylfumaric acid and arabitol that were up-regulated on Day2 of the time course experiment.

    CONCLUSIONS: This study provides information on genes expressed by G. boninense in metabolic pathways that may play a role in the initial infection of the host.

    Matched MeSH terms: Gene Expression Profiling
  14. Lau NS, Foong CP, Kurihara Y, Sudesh K, Matsui M
    PLoS One, 2014;9(1):e86368.
    PMID: 24466058 DOI: 10.1371/journal.pone.0086368
    The photosynthetic cyanobacterium, Synechocystis sp. strain 6803, is a potential platform for the production of various chemicals and biofuels. In this study, direct photosynthetic production of a biopolymer, polyhydroxyalkanoate (PHA), in genetically engineered Synechocystis sp. achieved as high as 14 wt%. This is the highest production reported in Synechocystis sp. under photoautotrophic cultivation conditions without the addition of a carbon source. The addition of acetate increased PHA accumulation to 41 wt%, and this value is comparable to the highest production obtained with cyanobacteria. Transcriptome analysis by RNA-seq coupled with real-time PCR was performed to understand the global changes in transcript levels of cells subjected to conditions suitable for photoautotrophic PHA biosynthesis. There was lower expression of most PHA synthesis-related genes in recombinant Synechocystis sp. with higher PHA accumulation suggesting that the concentration of these enzymes is not the limiting factor to achieving high PHA accumulation. In order to cope with the higher PHA production, cells may utilize enhanced photosynthesis to drive the product formation. Results from this study suggest that the total flux of carbon is the possible driving force for the biosynthesis of PHA and the polymerizing enzyme, PHA synthase, is not the only critical factor affecting PHA-synthesis. Knowledge of the regulation or control points of the biopolymer production pathways will facilitate the further use of cyanobacteria for biotechnological applications.
    Matched MeSH terms: Gene Expression Profiling*
  15. Ng KH, Ho CK, Phon-Amnuaisuk S
    PLoS One, 2012;7(10):e47216.
    PMID: 23071763 DOI: 10.1371/journal.pone.0047216
    Clustering is a key step in the processing of Expressed Sequence Tags (ESTs). The primary goal of clustering is to put ESTs from the same transcript of a single gene into a unique cluster. Recent EST clustering algorithms mostly adopt the alignment-free distance measures, where they tend to yield acceptable clustering accuracies with reasonable computational time. Despite the fact that these clustering methods work satisfactorily on a majority of the EST datasets, they have a common weakness. They are prone to deliver unsatisfactory clustering results when dealing with ESTs from the genes derived from the same family. The root cause is the distance measures applied on them are not sensitive enough to separate these closely related genes.
    Matched MeSH terms: Gene Expression Profiling/methods*
  16. Saghir FS, Rose IM, Dali AZ, Shamsuddin Z, Jamal AR, Mokhtar NM
    Int. J. Gynecol. Cancer, 2010 Jul;20(5):724-31.
    PMID: 20973258
    INTRODUCTION: Malignant transformation of type I endometrium involves alteration in gene expression with subsequent uncontrolled proliferation of altered cells.

    OBJECTIVE: The main objective of the present study was to identify the cancer-related genes and gene pathways in the endometrium of healthy and cancer patients.

    MATERIALS AND METHODS: Thirty endometrial tissues from healthy and type I EC patients were subjected to total RNA isolation. The RNA samples with good integrity number were hybridized to a new version of Affymetrix Human Genome GeneChip 1.0 ST array. We analyzed the results using the GeneSpring 9.0 GX and the Pathway Studio 6.1 software. For validation assay, quantitative real-time polymerase chain reaction was used to analyze 4 selected genes in normal and EC tissue.

    RESULTS: Of the 28,869 genes profiled, we identified 621 differentially expressed genes (2-fold) in the normal tissue and the tumor. Among these genes, 146 were up-regulated and 476 were down-regulated in the tumor as compared with the normal tissue (P < 0.001). Up-regulated genes included the v-erb-a erythroblastic leukemia viral oncogene homolog 3 (ErbB3), ErbB4, E74-like factor 3 (ELF3), and chemokine ligand 17 (CXCL17). The down-regulated genes included signal transducer and activator transcription 5B (STAT5b), transforming growth factor A receptor III (TGFA3), caveolin 1 (CAV1), and protein kinase C alpha (PKCA). The gene set enrichment analysis showed 10 significant gene sets with related genes (P < 0.05). The quantitative polymerase chain reaction of 4 selected genes using similar RNA confirmed the microarray results (P < 0.05).

    CONCLUSIONS: Identification of molecular pathways with their genes related to type I EC contribute to the understanding of pathophysiology of this cancer, probably leading to identifying potential biomarkers of the cancer.

    Matched MeSH terms: Gene Expression Profiling*
  17. Azlina A, Samsudin AR
    Med J Malaysia, 2004 May;59 Suppl B:166-7.
    PMID: 15468870
    In Malaysia, the field of genomics in toxicology is still in infancy. The purpose of this study is to focus on the use of toxicogenomics for determination of gene expressions changes in cultured human fibroblast cells treated with genotoxicology free biomaterial (using Ames test), a locally produced hyroxyapatite. Dose and time response is similar to Ames test with time interval up to 21 days. mRNA is extracted, followed with RT-PCR and polyacrilamide gel electrophoresis. Changes of the gene expressions compared to the non-treated fibroblast mRNA would suggest some gene interactions in the molecule level associated with the exposure of the fibroblast cell line to the biomaterials. Further analysis (cloning & sequencing) shall be carried out to investigate the genes involved as simple changes might not signified toxicity.
    Matched MeSH terms: Gene Expression Profiling*
  18. Moorthy K, Jaber AN, Ismail MA, Ernawan F, Mohamad MS, Deris S
    Methods Mol Biol, 2019;1986:255-266.
    PMID: 31115893 DOI: 10.1007/978-1-4939-9442-7_12
    In gene expression studies, missing values are a common problem with important consequences for the interpretation of the final data (Satija et al., Nat Biotechnol 33(5):495, 2015). Numerous bioinformatics examination tools are used for cancer prediction, including the data set matrix (Bailey et al., Cell 173(2):371-385, 2018); thus, it is necessary to resolve the problem of missing-values imputation. This chapter presents a review of the research on missing-values imputation approaches for gene expression data. By using local and global correlation of the data, we were able to focus mostly on the differences between the algorithms. We classified the algorithms as global, hybrid, local, or knowledge-based techniques. Additionally, this chapter presents suitable assessments of the different approaches. The purpose of this review is to focus on developments in the current techniques for scientists rather than applying different or newly developed algorithms with identical functional goals. The aim was to adapt the algorithms to the characteristics of the data.
    Matched MeSH terms: Gene Expression Profiling*
  19. Reza Etemadi M, Ling KH, Zainal Abidin S, Chee HY, Sekawi Z
    PLoS One, 2017;12(5):e0176947.
    PMID: 28558071 DOI: 10.1371/journal.pone.0176947
    Human rhinovirus (HRV) is the common virus that causes acute respiratory infection (ARI) and is frequently associated with lower respiratory tract infections (LRTIs). We aimed to investigate whether HRV infection induces a specific gene expression pattern in airway epithelial cells. Alveolar epithelial cell monolayers were infected with HRV species B (HRV-B). RNA was extracted from both supernatants and infected monolayer cells at 6, 12, 24 and 48 hours post infection (hpi) and transcriptional profile was analyzed using Affymetrix GeneChip and the results were subsequently validated using quantitative Real-time PCR method. HRV-B infects alveolar epithelial cells which supports implication of the virus with LRTIs. In total 991 genes were found differentially expressed during the course of infection. Of these, 459 genes were up-regulated whereas 532 genes were down-regulated. Differential gene expression at 6 hpi (187 genes up-regulated vs. 156 down-regulated) were significantly represented by gene ontologies related to the chemokines and inflammatory molecules indicating characteristic of viral infection. The 75 up-regulated genes surpassed the down-regulated genes (35) at 12 hpi and their enriched ontologies fell into discrete functional entities such as regulation of apoptosis, anti-apoptosis, and wound healing. At later time points of 24 and 48 hpi, predominated down-regulated genes were enriched for extracellular matrix proteins and airway remodeling events. Our data provides a comprehensive image of host response to HRV infection. The study suggests the underlying molecular regulatory networks genes which might be involved in pathogenicity of the HRV-B and potential targets for further validations and development of effective treatment.
    Matched MeSH terms: Gene Expression Profiling*
  20. Ealam Selvan M, Lim KS, Teo CH, Lim YY
    J Vis Exp, 2022 Oct 21.
    PMID: 36342167 DOI: 10.3791/64565
    Circular RNAs (circRNAs) are a class of non-coding RNAs that are formed via back-splicing. These circRNAs are predominantly studied for their roles as regulators of various biological processes. Notably, emerging evidence demonstrates that host circRNAs can be differentially expressed (DE) upon infection with pathogens (e.g., influenza and coronaviruses), suggesting a role for circRNAs in regulating host innate immune responses. However, investigations on the role of circRNAs during pathogenic infections are limited by the knowledge and skills required to carry out the necessary bioinformatic analysis to identify DE circRNAs from RNA sequencing (RNA-seq) data. Bioinformatics prediction and identification of circRNAs is crucial before any verification, and functional studies using costly and time-consuming wet-lab techniques. To solve this issue, a step-by-step protocol of in silico prediction and characterization of circRNAs using RNA-seq data is provided in this manuscript. The protocol can be divided into four steps: 1) Prediction and quantification of DE circRNAs via the CIRIquant pipeline; 2) Annotation via circBase and characterization of DE circRNAs; 3) CircRNA-miRNA interaction prediction through Circr pipeline; 4) functional enrichment analysis of circRNA parental genes using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). This pipeline will be useful in driving future in vitro and in vivo research to further unravel the role of circRNAs in host-pathogen interactions.
    Matched MeSH terms: Gene Expression Profiling/methods
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