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siRNA-mediated inhibition of survivin gene enhances the anti-cancer effect of etoposide in U-937 acute myeloid leukemia cells

Jafarlou M, Baradaran B, Shanehbandi D, Saedi TA, Jafarlou V, Ismail P, et al.

Cell Mol Biol (Noisy-le-grand), 2016 May 30;62(6):44-9.
PMID: 27262801

Acute myeloid leukemia (AML) is one of the most frequent types of leukemia which mostly affects adult people. Resistance to therapeutic drugs is considered as a major clinical concern resulting in a weaker response to chemotherapy, disease relapse and decreased survival rate. Survivin, a member of Inhibitor of Apoptosis Proteins (IAPs), is associated with drug resistance and inhibition of apoptotic mechanisms in numerous hematological malignancies. In the present study, we examined the combined effect of etoposide and siRNA-mediated silencing of survivin on U-937 acute myeloid leukemia cells. The AML cells were transfected with survivin specific siRNA and gene knockdown was confirmed by quantitative real time PCR and western blotting. Subsequently, U-937 cells were assessed for response to etoposide treatment and apoptosis rate was measured with flowcytometery. The cytotoxic effects in siRNA-etoposide group were measured and compared to etoposide single therapy group. Survivin siRNA effectively knocked down the mRNA and protein levels of survivin, which led to lower cell proliferation and enhanced apoptosis. Furthermore, combined treatment of etoposide and survivin siRNA synergistically increased the cell toxic effects of etoposide and its ability to induce apoptosis.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext mRNA profile provides novel insights into stress adaptation in mud crab megalopa, Scylla paramamosain after salinity stress

Zhang Y, Wu Q, Fang S, Li S, Zheng H, Zhang Y, et al.

BMC Genomics, 2020 Aug 14;21(1):559.
PMID: 32795331 DOI: 10.1186/s12864-020-06965-5

BACKGROUND: Mud crab, Scylla paramamosain, a euryhaline crustacean species, mainly inhabits the Indo-Western Pacific region. Wild mud crab spawn in high-salt condition and the salinity reduced with the growth of the hatching larvae. When the larvae grow up to megalopa, they migrate back to estuaries and coasts in virtue of the flood tide, settle and recruit adult habitats and metamorphose into the crablet stage. Adult crab can even survive in a wide salinity of 0-35 ppt. To investigate the mRNA profile after salinity stress, S. paramamosain megalopa were exposed to different salinity seawater (low, 14 ppt; control, 25 ppt; high, 39 ppt).
RESULTS: Firstly, from the expression profiles of Na+/K+/2Cl- cotransporter, chloride channel protein 2, and ABC transporter, it turned out that the 24 h might be the most influenced duration in the short-term stress. We collected megalopa under different salinity for 24 h and then submitted to mRNA profiling. Totally, 57.87 Gb Clean Data were obtained. The comparative genomic analysis detected 342 differentially expressed genes (DEGs). The most significantly DEGs include gamma-butyrobetaine dioxygenase-like, facilitated trehalose transporter Tret1, sodium/potassium-transporting ATPase subunit alpha, rhodanese 1-like protein, etc. And the significantly enriched pathways were lysine degradation, choline metabolism in cancer, phospholipase D signaling pathway, Fc gamma R-mediated phagocytosis, and sphingolipid signaling pathway. The results indicate that in the short-term salinity stress, the megalopa might regulate some mechanism such as metabolism, immunity responses, osmoregulation to adapt to the alteration of the environment.
CONCLUSIONS: This study represents the first genome-wide transcriptome analysis of S. paramamosain megalopa for studying its stress adaption mechanisms under different salinity. The results reveal numbers of genes modified by salinity stress and some important pathways, which will provide valuable resources for discovering the molecular basis of salinity stress adaptation of S. paramamosain larvae and further boost the understanding of the potential molecular mechanisms of salinity stress adaptation for crustacean species.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext mRNA expression of EgCHI1, EgCHI2, and EgCHI3 in oil palm leaves (Elaeis guineesis Jacq.) after treatment with Ganoderma boninense pat. and Trichoderma harzianum Rifai

Naher L, Tan SG, Ho CL, Yusuf UK, Ahmad SH, Abdullah F

ScientificWorldJournal, 2012;2012:647504.
PMID: 22919345 DOI: 10.1100/2012/647504

Basal stem rot (BSR) disease caused by the fungus Ganoderma boninense is the most serious disease affecting the oil palm; this is because the disease escapes the early disease detection. The biocontrol agent Trichoderma harzianum can protect the disease only at the early stage of the disease. In the present study, the expression levels of three oil palm (Elaeis guineensis Jacq.) chitinases encoding EgCHI1, EgCHI2, and EgCHI3 at 2, 5, and 8 weeks inoculation were measured in oil palm leaves from plants treated with G. boninense or T. harzianum alone or both.

Matched MeSH terms: RNA, Messenger/genetics*
Withaferin A Protects Against High-Fat Diet-Induced Obesity Via Attenuation of Oxidative Stress, Inflammation, and Insulin Resistance

Abu Bakar MH, Azmi MN, Shariff KA, Tan JS

Appl Biochem Biotechnol, 2019 May;188(1):241-259.
PMID: 30417321 DOI: 10.1007/s12010-018-2920-2

Withaferin A (WA), a bioactive constituent derived from Withania somnifera plant, has been shown to exhibit many qualifying properties in attenuating several metabolic diseases. The current investigation sought to elucidate the protective mechanisms of WA (1.25 mg/kg/day) on pre-existing obese mice mediated by high-fat diet (HFD) for 12 weeks. Following dietary administration of WA, significant metabolic improvements in hepatic insulin sensitivity, adipocytokines with enhanced glucose tolerance were observed. The hepatic oxidative functions of obese mice treated with WA were improved via augmented antioxidant enzyme activities. The levels of serum pro-inflammatory cytokines and hepatic mRNA expressions of toll-like receptor (TLR4), nuclear factor κB (NF-κB), tumor necrosis factor-α (TNF-α), chemokine (C-C motif) ligand-receptor, and cyclooxygenase 2 (COX2) in HFD-induced obese mice were reduced. Mechanistically, WA increased hepatic mRNA expression of peroxisome proliferator-activated receptors (PPARs), cluster of differentiation 36 (CD36), fatty acid synthase (FAS), carnitine palmitoyltransferase 1 (CPT1), glucokinase (GCK), phosphofructokinase (PFK), and phosphoenolpyruvate carboxykinase (PCK1) that were associated with enhanced lipid and glucose metabolism. Taken together, these results indicate that WA exhibits protective effects against HFD-induced obesity through attenuation of hepatic inflammation, oxidative stress, and insulin resistance in mice.

Matched MeSH terms: RNA, Messenger/genetics
Vacuolar-ATPase (V-ATPase) Mediates Progesterone-Induced Uterine Fluid Acidification in Rats

Karim K, Giribabu N, Muniandy S, Salleh N

J. Membr. Biol., 2016 04;249(1-2):65-76.
PMID: 26403527 DOI: 10.1007/s00232-015-9848-z

We hypothesized that progesterone-induced decrease in uterine fluid pH involves V-ATPase. In this study, expression and functional activity of V-ATPase in uterus were investigated under progesterone influence. Ovariectomized adult female rats received subcutaneous injection of estradiol-17β (1 µg/kg/day) or progesterone (20 mg/kg/day) for 3 days or 3 days estradiol-17β followed by 3 days vehicle, progesterone, or estradiol-17β plus progesterone. Mifepristone, a progesterone receptor blocker, was concomitantly given to the rats which received progesterone. A day after last injection, rate of uterine fluid secretion, its HCO3 (-) concentration, and pH were determined via in vivo uterine perfusion in rats under anesthesia. V-ATPase inhibitor, bafilomycin, was introduced into the perfusion buffer, and changes in these parameters were observed. Expression of V-ATPase A1 and B1/2 proteins and mRNAs in uterus were quantified by Western blotting and real-time PCR, respectively. Distribution of these proteins was observed by immunohistochemistry. Our findings showed that under progesterone influence, uterine fluid secretion rate, HCO3 (-) concentration, and pH were significantly reduced. Administration of bafilomycin did not cause significant changes in fluid secretion rate; however, HCO3 (-) concentration and pH were significantly elevated. In parallel with these changes, expression of V-ATPase A1 and B1/2 proteins and mRNAs were significantly increased with these proteins highly distributed in uterine luminal and glandular epithelia. In conclusion, increased expression and functional activity of V-ATPase were most likely responsible for the decreased in uterine fluid pH observed under progesterone influence.

Matched MeSH terms: RNA, Messenger/genetics
Upregulation of SOX-2, FZD9, Nestin, OCT-4 and FGF-4 expression in human chorion derived-stem cells after angiogenic induction

Abdul Rahman H, Manzor NF, Tan GC, Tan AE, Chua KH

Med J Malaysia, 2008 Jul;63 Suppl A:57-8.
PMID: 19024982

Angiogenic induction was made to promote angiogenesis by differentiating stem cells towards endothelial cells. However, the stemness property of induced cells has not been revealed yet. Hence, we aim to evaluate the differential mRNA expression of stemness genes in human chorion-derived stem cells (CDSC) after being cultured in EDM50 comprised bFGF and VEGF. Results indicated that CDSC cultured in EMD50 expressed significantly higher mRNA level of Sox-2, FZD9, BST-1 and Nestin. In addition Oct-4, FGF-4 and ABCG-2 were also upregulated. Our finding suggested that CDSC after angiogenic induction enhanced its stem cell properties. This could be contributed for the mechanism of stem cell therapy in ischemic problem.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext Upregulation of Phosphatidylinositol 3-Kinase (PI3K) Enhances Ethylene Biosynthesis and Accelerates Flower Senescence in Transgenic Nicotiana tabacum L

Dek MSP, Padmanabhan P, Sherif S, Subramanian J, Paliyath AG

Int J Mol Sci, 2017 Jul 15;18(7).
PMID: 28714880 DOI: 10.3390/ijms18071533

Phosphatidylinositol 3-kinase (PI3K) is a key enzyme that phosphorylates phosphatidylinositol at 3'-hydroxyl position of the inositol head group initiating the generation of several phosphorylated phosphatidylinositols, collectively referred to as phosphoinositides. The function of PI3K in plant senescence and ethylene signal transduction process was studied by expression ofSolanum lycopersicumPI3K in transgenicNicotiana tabacum, and delineating its effect on flower senescence. Detached flowers of transgenic tobacco plants with overexpressedSl-PI3K(OX) displayed accelerated senescence and reduced longevity, when compared to the flowers of wild type plants. Flowers from PI3K-overexpressing plants showed enhanced ethylene production and upregulated expression of 1-aminocyclopropane-1-carboxylic acid oxidase 1 (ACO1). Real time polymerase chain reaction (PCR) analysis showed thatPI3Kwas expressed at a higher level in OX flowers than in the control. Seedlings of OX-lines also demonstrated a triple response phenotype with characteristic exaggerated apical hook, shorter hypocotyls and increased sensitivity to 1-aminocyclopropane-1-carboxylate than the control wild type seedlings. In floral tissue from OX-lines,Solanum lycopersicumphosphatidylinositol 3-kinase green fluorescent protein (PI3K-GFP) chimera protein was localized primarily in stomata, potentially in cytoplasm and membrane adjacent to stomatal pores in the guard cells. Immunoblot analysis of PI3K expression in OX lines demonstrated increased protein level compared to the control. Results of the present study suggest that PI3K plays a crucial role in senescence by enhancing ethylene biosynthesis and signaling.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext Transcripts and MicroRNAs Responding to Salt Stress in Musa acuminata Colla (AAA Group) cv. Berangan Roots

Lee WS, Gudimella R, Wong GR, Tammi MT, Khalid N, Harikrishna JA

PLoS One, 2015;10(5):e0127526.
PMID: 25993649 DOI: 10.1371/journal.pone.0127526

Physiological responses to stress are controlled by expression of a large number of genes, many of which are regulated by microRNAs. Since most banana cultivars are salt-sensitive, improved understanding of genetic regulation of salt induced stress responses in banana can support future crop management and improvement in the face of increasing soil salinity related to irrigation and climate change. In this study we focused on determining miRNA and their targets that respond to NaCl exposure and used transcriptome sequencing of RNA and small RNA from control and NaCl-treated banana roots to assemble a cultivar-specific reference transcriptome and identify orthologous and Musa-specific miRNA responding to salinity. We observed that, banana roots responded to salinity stress with changes in expression for a large number of genes (9.5% of 31,390 expressed unigenes) and reduction in levels of many miRNA, including several novel miRNA and banana-specific miRNA-target pairs. Banana roots expressed a unique set of orthologous and Musa-specific miRNAs of which 59 respond to salt stress in a dose-dependent manner. Gene expression patterns of miRNA compared with those of their predicted mRNA targets indicated that a majority of the differentially expressed miRNAs were down-regulated in response to increased salinity, allowing increased expression of targets involved in diverse biological processes including stress signaling, stress defence, transport, cellular homeostasis, metabolism and other stress-related functions. This study may contribute to the understanding of gene regulation and abiotic stress response of roots and the high-throughput sequencing data sets generated may serve as important resources related to salt tolerance traits for functional genomic studies and genetic improvement in banana.

Matched MeSH terms: RNA, Messenger/genetics
Transcriptome analysis of feline infectious peritonitis virus infection

Mehrbod P, Harun MS, Shuid AN, Omar AR

Methods Mol Biol, 2015;1282:241-50.
PMID: 25720485 DOI: 10.1007/978-1-4939-2438-7_20

Feline infectious peritonitis (FIP) is a lethal systemic disease caused by FIP virus (FIPV). There are no effective vaccines or treatment available, and the virus virulence determinants and pathogenesis are not fully understood. Here, we describe the sequencing of RNA extracted from Crandell Rees Feline Kidney (CRFK) cells infected with FIPV using the Illumina next-generation sequencing approach. Bioinformatics analysis, based on Felis catus 2X annotated shotgun reference genome, using CLC bio Genome Workbench is used to map both control and infected cells. Kal's Z test statistical analysis is used to analyze the differentially expressed genes from the infected CRFK cells. In addition, RT-qPCR analysis is used for further transcriptional profiling of selected genes in infected CRFK cells and Peripheral Blood Mononuclear Cells (PBMCs) from healthy and FIP-diagnosed cats.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext Transcriptome Analysis and Differential Gene Expression on the Testis of Orange Mud Crab, Scylla olivacea, during Sexual Maturation

Waiho K, Fazhan H, Shahreza MS, Moh JH, Noorbaiduri S, Wong LL, et al.

PLoS One, 2017;12(1):e0171095.
PMID: 28135340 DOI: 10.1371/journal.pone.0171095

Adequate genetic information is essential for sustainable crustacean fisheries and aquaculture management. The commercially important orange mud crab, Scylla olivacea, is prevalent in Southeast Asia region and is highly sought after. Although it is a suitable aquaculture candidate, full domestication of this species is hampered by the lack of knowledge about the sexual maturation process and the molecular mechanisms behind it, especially in males. To date, data on its whole genome is yet to be reported for S. olivacea. The available transcriptome data published previously on this species focus primarily on females and the role of central nervous system in reproductive development. De novo transcriptome sequencing for the testes of S. olivacea from immature, maturing and mature stages were performed. A total of approximately 144 million high-quality reads were generated and de novo assembled into 160,569 transcripts with a total length of 142.2 Mb. Approximately 15-23% of the total assembled transcripts were annotated when compared to public protein sequence databases (i.e. UniProt database, Interpro database, Pfam database and Drosophila melanogaster protein database), and GO-categorised with GO Ontology terms. A total of 156,181 high-quality Single-Nucleotide Polymorphisms (SNPs) were mined from the transcriptome data of present study. Transcriptome comparison among the testes of different maturation stages revealed one gene (beta crystallin like gene) with the most significant differential expression-up-regulated in immature stage and down-regulated in maturing and mature stages. This was further validated by qRT-PCR. In conclusion, a comprehensive transcriptome of the testis of orange mud crabs from different maturation stages were obtained. This report provides an invaluable resource for enhancing our understanding of this species' genome structure and biology, as expressed and controlled by their gonads.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext Transcription Factor CREB3L1 Regulates Endoplasmic Reticulum Stress Response Genes in the Osmotically Challenged Rat Hypothalamus

Greenwood M, Greenwood MP, Paton JF, Murphy D

PLoS One, 2015;10(4):e0124956.
PMID: 25915053 DOI: 10.1371/journal.pone.0124956

Arginine vasopressin (AVP) is synthesised in magnocellular neurons (MCNs) of supraoptic nucleus (SON) and paraventricular nucleus (PVN) of the hypothalamus. In response to the hyperosmotic stressors of dehydration (complete fluid deprivation, DH) or salt loading (drinking 2% salt solution, SL), AVP synthesis increases in MCNs, which over-burdens the protein folding machinery in the endoplasmic reticulum (ER). ER stress and the unfolded protein response (UPR) are signaling pathways that improve ER function in response to the accumulation of misfold/unfold protein. We asked whether an ER stress response was activated in the SON and PVN of DH and SL rats. We observed increased mRNA expression for the immunoglobulin heavy chain binding protein (BiP), activating transcription factor 4 (Atf4), C/EBP-homologous protein (Chop), and cAMP responsive element binding protein 3 like 1 (Creb3l1) in both SON and PVN of DH and SL rats. Although we found no changes in the splicing pattern of X box-binding protein 1 (Xbp1), an increase in the level of the unspliced form of Xbp1 (Xbp1U) was observed in DH and SL rats. CREB3L1, a novel ER stress inducer, has been shown to be activated by ER stress to regulate the expression of target genes. We have previously shown that CREB3L1 is a transcriptional regulator of the AVP gene; however, a role for CREB3L1 in the response to ER stress has yet to be investigated in MCNs. Here, we used lentiviral vectors to introduce a dominant negative form of CREB3L1 (CREB3L1DN) in the rat SON. Expression of CREB3L1DN in the SON decreased Chop and Xbp1U mRNA levels, but not BiP and Atf4 transcript expression. CREB3L1 is thus implicated as a transcriptional mediator of the ER stress response in the osmotically stimulated SON.

Matched MeSH terms: RNA, Messenger/genetics
Transcript, methylation and molecular docking analyses of the effects of HDAC inhibitors, SAHA and Dacinostat, on SMN2 expression in fibroblasts of SMA patients

Mohseni J, Al-Najjar BO, Wahab HA, Zabidi-Hussin ZA, Sasongko TH

J Hum Genet, 2016 Sep;61(9):823-30.
PMID: 27251006 DOI: 10.1038/jhg.2016.61

Several histone deacetylase inhibitors (HDACis) are known to increase Survival Motor Neuron 2 (SMN2) expression for the therapy of spinal muscular atrophy (SMA). We aimed to compare the effects of suberoylanilide hydroxamic acid (SAHA) and Dacinostat, a novel HDACi, on SMN2 expression and to elucidate their acetylation effects on the methylation of the SMN2. Cell-based assays using type I and type II SMA fibroblasts examined changes in transcript expressions, methylation levels and protein expressions. In silico methods analyzed the intermolecular interactions between each compound and HDAC2/HDAC7. SMN2 mRNA transcript levels and SMN protein levels showed notable increases in both cell types, except for Dacinostat exposure on type II cells. However, combined compound exposures showed less pronounced increase in SMN2 transcript and SMN protein level. Acetylation effects of SAHA and Dacinostat promoted demethylation of the SMN2 promoter. The in silico analyses revealed identical binding sites for both compounds in HDACs, which could explain the limited effects of the combined exposure. With the exception on the effect of Dacinostat in Type II cells, we have shown that SAHA and Dacinostat increased SMN2 transcript and protein levels and promoted demethylation of the SMN2 gene.

Matched MeSH terms: RNA, Messenger/genetics
Thymoquinone-rich fraction nanoemulsion (TQRFNE) decreases Aβ40 and Aβ42 levels by modulating APP processing, up-regulating IDE and LRP1, and down-regulating BACE1 and RAGE in response to high fat/cholesterol diet-induced rats

Ismail N, Ismail M, Azmi NH, Bakar MFA, Yida Z, Abdullah MA, et al.

Biomed Pharmacother, 2017 Nov;95:780-788.
PMID: 28892789 DOI: 10.1016/j.biopha.2017.08.074

Though the causes of Alzheimer's disease (AD) are yet to be understood, much evidence has suggested that excessive amyloid-β (Aβ) accumulation due to abnormal amyloid-β precursor protein (APP) processing and Aβ metabolism are crucial processes towards AD pathogenesis. Hence, approaches aiming at APP processing and Aβ metabolism are currently being actively pursued for the management of AD. Studies suggest that high cholesterol and a high fat diet have harmful effects on cognitive function and may instigate the commencement of AD pathogenesis. Despite the neuropharmacological attributes of black cumin seed (Nigella sativa) extracts and its main active compound, thymoquinone (TQ), limited records are available in relation to AD research. Nanoemulsion (NE) is exploited as drug delivery systems due to their capacity of solubilising non-polar active compounds and is widely examined for brain targeting. Herewith, the effects of thymoquinone-rich fraction nanoemulsion (TQRFNE), thymoquinone nanoemulsion (TQNE) and their counterparts' conventional emulsion in response to high fat/cholesterol diet (HFCD)-induced rats were investigated. Particularly, the Aβ generation; APP processing, β-secretase 1 (BACE1), γ-secretases of presenilin 1 (PSEN1) and presenilin 2 (PSEN2), Aβ degradation; insulin degrading enzyme (IDE), Aβ transportation; low density lipoprotein receptor-related protein 1 (LRP1) and receptor for advanced glycation end products (RAGE) were measured in brain tissues. TQRFNE reduced the brain Aβ fragment length 1-40 and 1-42 (Aβ40 and Aβ42) levels, which would attenuate the AD pathogenesis. This reduction could be due to the modulation of β- and γ-secretase enzyme activity, and the Aβ degradation and transportation in/out of the brain. The findings show the mechanistic actions of TQRFNE in response to high fat and high cholesterol diet associated to Aβ generation, degradation and transportation in the rat's brain tissue.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext Thermotolerance and molecular chaperone function of an SGT1-like protein from the psychrophilic yeast, Glaciozyma antarctica

Yusof NA, Hashim NH, Beddoe T, Mahadi NM, Illias RM, Bakar FD, et al.

Cell Stress Chaperones, 2016 Jul;21(4):707-15.
PMID: 27154490 DOI: 10.1007/s12192-016-0696-2

The ability of eukaryotes to adapt to an extreme range of temperatures is critically important for survival. Although adaptation to extreme high temperatures is well understood, reflecting the action of molecular chaperones, it is unclear whether these molecules play a role in survival at extremely low temperatures. The recent genome sequencing of the yeast Glaciozyma antarctica, isolated from Antarctic sea ice near Casey Station, provides an opportunity to investigate the role of molecular chaperones in adaptation to cold temperatures. We isolated a G. antarctica homologue of small heat shock protein 20 (HSP20), GaSGT1, and observed that the GaSGT1 mRNA expression in G. antarctica was markedly increased following culture exposure at low temperatures. Additionally, we demonstrated that GaSGT1 overexpression in Escherichia coli protected these bacteria from exposure to both high and low temperatures, which are lethal for growth. The recombinant GaSGT1 retained up to 60 % of its native luciferase activity after exposure to luciferase-denaturing temperatures. These results suggest that GaSGT1 promotes cell thermotolerance and employs molecular chaperone-like activity toward temperature assaults.

Matched MeSH terms: RNA, Messenger/genetics
The role of specific Smad linker region phosphorylation in TGF-β mediated expression of glycosaminoglycan synthesizing enzymes in vascular smooth muscle

Rostam MA, Kamato D, Piva TJ, Zheng W, Little PJ, Osman N

Cell Signal, 2016 08;28(8):956-66.
PMID: 27153775 DOI: 10.1016/j.cellsig.2016.05.002

Hyperelongation of glycosaminoglycan chains on proteoglycans facilitates increased lipoprotein binding in the blood vessel wall and the development of atherosclerosis. Increased mRNA expression of glycosaminoglycan chain synthesizing enzymes in vivo is associated with the development of atherosclerosis. In human vascular smooth muscle, transforming growth factor-β (TGF-β) regulates glycosaminoglycan chain hyperelongation via ERK and p38 as well as Smad2 linker region (Smad2L) phosphorylation. In this study, we identified the involvement of TGF-β receptor, intracellular serine/threonine kinases and specific residues on transcription factor Smad2L that regulate glycosaminoglycan synthesizing enzymes. Of six glycosaminoglycan synthesizing enzymes, xylosyltransferase-1, chondroitin sulfate synthase-1, and chondroitin sulfotransferase-1 were regulated by TGF-β. In addition ERK, p38, PI3K and CDK were found to differentially regulate mRNA expression of each enzyme. Four individual residues in the TGF-β receptor mediator Smad2L can be phosphorylated by these kinases and in turn regulate the synthesis and activity of glycosaminoglycan synthesizing enzymes. Smad2L Thr220 was phosphorylated by CDKs and Smad2L Ser250 by ERK. p38 selectively signalled via Smad2L Ser245. Phosphorylation of Smad2L serine residues induced glycosaminoglycan synthesizing enzymes associated with glycosaminoglycan chain elongation. Phosphorylation of Smad2L Thr220 was associated with XT-1 enzyme regulation, a critical enzyme in chain initiation. These findings provide a deeper understanding of the complex signalling pathways that contribute to glycosaminoglycan chain modification that could be targeted using pharmacological agents to inhibit the development of atherosclerosis.

Matched MeSH terms: RNA, Messenger/genetics
The role of leptin and ghrelin in appetite regulation in the Australian Spinifex hopping mouse, Notomys alexis, during long-term water deprivation

Donald JA, Hamid NKA, McLeod JL

Gen Comp Endocrinol, 2017 04 01;244:201-208.
PMID: 27102941 DOI: 10.1016/j.ygcen.2016.04.015

Water deprivation of the Spinifex hopping mouse, Notomys alexis, induced a biphasic pattern of food intake with an initial hypophagia that was followed by an increased, and then sustained food intake. The mice lost approximately 20% of their body mass and there was a loss of white adipose tissue. Stomach ghrelin mRNA was significantly higher at day 2 of water deprivation but then returned to the same levels as water-replete (day 0) mice for the duration of the experiment. Plasma ghrelin was unaffected by water deprivation except at day 10 where it was significantly increased. Plasma leptin levels decreased at day 2 and day 5 of water deprivation, and then increased significantly by the end of the water deprivation period. Water deprivation caused a significant decrease in skeletal muscle leptin mRNA expression at days 2 and 5, but then it returned to day 0 levels by day 29. In the hypothalamus, water deprivation caused a significant up-regulation in both ghrelin and neuropeptide Y mRNA expression, respectively. In contrast, hypothalamic GHSR1a mRNA expression was significantly down-regulated. A significant increase in LepRb mRNA expression was observed at days 17 and 29 of water deprivation. This study demonstrated that the sustained food intake in N. alexis during water deprivation was uncoupled from peripheral appetite-regulating signals, and that the hypothalamus appears to play an important role in regulating food intake; this may contribute to the maintenance of fluid balance in the absence of free water.

Matched MeSH terms: RNA, Messenger/genetics
The ribosomal protein L19 mRNA is induced by copper exposure in the swordtail fish, Xiphophorus helleri

Aliza D, Tey CL, Ismail IS, Kuah MK, Shu-Chien AC, Muhammad TS

Mol Biol Rep, 2012 Apr;39(4):4823-9.
PMID: 21956757 DOI: 10.1007/s11033-011-1275-3

Teleosts are useful vertebrate model species for understanding copper toxicity due to the dual entry route for copper intake via the gills and intestine. In this present study, we utilized the differential display reverse transcription-polymerase chain reaction to isolate potential novel hepatic genes induced by sublethal copper exposure in the freshwater swordtail fish, Xiphophorus helleri. Full length cloning of a cDNA fragment induced by copper exposure to 1 μg/ml during 24 h resulted in the positive identification of a hepatic ribosomal protein L19 (RPL19) gene. Further characterization of this gene revealed that its transcriptional expression was dependent on dosage and time of copper exposure. This study describes for the first time the involvement of RPL19 in copper toxicity, probably as a result of increase in ribosome synthesis rate to support activities such as cellular protein translation, transcriptional activation and mRNA stabilization during sublethal copper exposure.

Matched MeSH terms: RNA, Messenger/genetics
The mRNA expression of soluble urokinase plasminogen activator surface receptor in human adipose tissue is positively correlated with body mass index

Ng HF, Chin KF, Chan KG, Ngeow YF

Genome, 2015 Jun;58(6):315-21.
PMID: 26284904 DOI: 10.1139/gen-2015-0028

suPLAUR is the transcript variant that encodes the soluble form of the urokinase plasminogen activator surface receptor (suPLAUR). This soluble protein has been shown to enhance leukocyte migration and adhesion, and its circulatory level is increased in inflammatory states. In this pilot study, we used RNA-Seq to examine the splicing pattern of PLAUR in omental adipose tissues from obese and lean individuals. Of the three transcript variants of the PLAUR gene, only the proportion of suPLAUR (transcript variant 2) increases in obesity. After removing the effects of gender and age, the expression of suPLAUR is positively correlated with body mass index. This observation was validated using RT-qPCR with an independent cohort of samples. Additionally, in our RNA-Seq differential expression analysis, we also observed, in obese adipose tissues, an up-regulation of genes encoding other proteins involved in the process of chemotaxis and leukocyte adhesion; of particular interest is the integrin beta 2 (ITGB2) that is known to interact with suPLAUR in leukocyte adhesion. These findings suggest an important role for suPLAUR in the recruitment of immune cells to obese adipose tissue, in the pathogenesis of obesity.

Matched MeSH terms: RNA, Messenger/genetics*
Fulltext The involvement of miR-23a/APAF1 regulation axis in colorectal cancer

Yong FL, Wang CW, Roslani AC, Law CW

Int J Mol Sci, 2014 Jul 02;15(7):11713-29.
PMID: 24992592 DOI: 10.3390/ijms150711713

Recent advances in microRNAome have made microRNAs (miRNAs) a compelling novel class of biomarker in cancer biology. In the present study, the role of miR-23a in the carcinogenesis of colorectal cancer (CRC) was investigated. Cell viability, apoptosis, and caspase 3/7 activation analyses were conducted to determine the potentiality of apoptosis resistance function of miR-23a in CRC. Luciferase assay was performed to verify a putative target site of miR-23a in the 3'-UTR of apoptosis protease activating factor 1 (APAF1) mRNA. The expression levels of miR-23a and APAF1 in CRC cell lines (SW480 and SW620) and clinical samples were assessed using reverse transcription-quantitative real-time PCR (RT-qPCR) and Western blot. We found that the inhibition of miR-23a in SW480 and SW620 cell lines resulted in significant reduction of cell viability and promotion of cell apoptosis. Moreover, miR-23a up-regulation was coupled with APAF1 down-regulation in CRC tissue samples. Taken together, miR-23a was identified to regulate apoptosis in CRC. Our study highlights the potential application of miR-23a/APAF1 regulation axis in miRNA-based therapy and prognostication.

Matched MeSH terms: RNA, Messenger/genetics
Fulltext The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts

Khor SC, Razak AM, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S

PLoS One, 2016;11(2):e0149265.
PMID: 26885980 DOI: 10.1371/journal.pone.0149265

Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF) and α-tocopherol (ATF) in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal) expression, myogenic differentiation and myogenic regulatory factors (MRFs) expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

Matched MeSH terms: RNA, Messenger/genetics

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