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Genetics and exercise: an introduction
Published in Adam P. Sharples, James P. Morton, Henning Wackerhage, Molecular Exercise Physiology, 2022
Claude Bouchard, Henning Wackerhage
How is a gene “read” to produce a protein? Francis Crick wrote in 1956 something in his notebook which he called the “central dogma”. Today, this unpublished notion is widely known as the central dogma of molecular biology. It describes how the biological information flows in the “DNA → RNA → protein” direction. According to the dogma, DNA is equivalent to the instructions for the book of life. RNA is very similar to DNA, but it is single-stranded, whereas DNA is double-stranded (i.e. the double helix), and the sugar in RNA is a ribose, whereas the sugar in DNA is a deoxyribose. Also known as “messenger” RNA (mRNA), the RNA copies and delivers the DNA “message” to the protein-making machinery of the cell (in the ribosome) to make the protein. The making or synthesis of RNA from DNA is termed transcription (RNA synthesis also described as gene expression) and the process of protein synthesis from RNA is termed translation. Figure 3.7 illustrates Crick’s central dogma. It is important considering recent advances in molecular biology to recognise that the central dogma is incomplete and that there are exceptions to the dogma.
Basic Cell Biology
Published in Kedar N. Prasad, Handbook of RADIOBIOLOGY, 2020
Like DNA, RNA is also a polynucleotide chain and consists of four bases, sugar, and phosphoric acid. RNA differs from DNA in the following respects: (1) it has sugar in the form of ribose rather than deoxyribose, and (2) it has pyrimidine base uracil in place of thymine. The enzyme RNA polymerase is required for RNA synthesis, and the enzyme RNAse degrades RNA. There are several classes of mammalian RNA, three of which are most important: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). All these types of RNA participate in protein biosynthesis.
Clinical Problems Associated with Diabetes Mellitus
Published in Grant N. Pierce, Robert E. Beamish, Naranjan S. Dhalla, Heart Dysfunction in Diabetes, 2019
Grant N. Pierce, Robert E. Beamish, Naranjan S. Dhalla
The metabolic effects of insulin are numerous and varied. It has an influence on carbohydrate, fat, and protein anabolic and catabolic pathways in liver, muscle, and adipose tissues of the body (Figure 5). Insulin promotes glucose entry into all three types of cells, although its effect is only indirect in the case of liver through a stimulation of intracellular glucokinase activity.66 Glucose release from the liver is inhibited. Cellular glycolysis and glycogenesis is enhanced. In muscle this is achieved by a stimulatory action of insulin on UDPG-glucosyltransferase, the regulatory enzyme for glycogen synthesis from glucose substrate. The conversion of amino acids to glucose is inhibited in the liver by insulin. Protein synthesis is uniformly stimulated by insulin in all three of these cell types.67–69 RNA synthesis is also enhanced. Insulin increases the rate of triglyceride synthesis from glucose or acetate and fatty acid synthesis and esterification. Conversely, the release of lipids like glycerol and fatty acids from adipose tissue is inhibited by insulin.
Comparison of media milling and microfluidization methods for engineering of nanocrystals: a case study
Published in Drug Development and Industrial Pharmacy, 2020
Manasi Chogale, Sandip Gite, Vandana Patravale
The model drug in this study is an antimycobacterial drug, ‘RIF’ used as the first-line of therapy for the treatment of tuberculosis (TB). It is used in combination with other antibiotics like isoniazid, pyrazinamide, and ethambutol for the treatment of active TB. It acts by inhibition of bacterial DNA-dependent RNA polymerase and hence the bacterial DNA-dependent RNA synthesis. It is a BCS class-II drug (poorly soluble) with solubility in water as low as 41.3 µg/mL and is administered in doses as high as 600 mg. The most serious adverse effect associated with the administration of RIF is hepatotoxicity [14]. Formulation of RIF as a nanoformulation can enhance the solubility of the drug and may help lower the required dose. Hence, RIF nanocrystals (RIF NCs) were proposed to be formulated by milling and microfluidization method and the products obtained by both the methods were investigated. The developed nanocrystals would further be formulated for direct pulmonary administration.
Wound healing activity of neferine in experimental diabetic rats through the inhibition of inflammatory cytokines and nrf-2 pathway
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2020
Juan Li, Haiyan Chou, Lei Li, Hao Li, Zhengjun Cui
The expression patterns of Nrf2, Keap 1, collagen-1, TGF-β and α-SMA were investigated using quantitative real-time PCR. The total RNA extraction from the wound tissue sample was carried out using with TRIzol (Ambion, Austin, TX, USA). The convertion of RNA synthesis into cDNA was carried out by reverse transcription reaction (Thermo Scientific kit, Burlington, Canada). Then, the PCR analyses of cDNA sample were carried out using SYBR® Premix Ex Taq™ (Tli RNaseH Plus) (Applied Biosystems, 850 Lincoln Centre Drive, Foster City, California 94,404, USA). The reaction mixture comprise of 9 μL of qPCR Master Mix (EURx Company, Gdańsk, Poland), 10 ng of cDNA solution and 20 μL of all primers. The qPCR data obtained was scrutinized using the DDCT technique. The PCR results, with the Ct value (elbow value of a PCR amplification curve) and the 2 − ΔΔCT method applied to calculate the relative expression of the target genes. The data were normalized with GAPDH of the same sample against controls.
Functional and transcriptomic analysis of extracellular vesicles identifies calprotectin as a new prognostic marker in peripheral arterial disease (PAD)
Published in Journal of Extracellular Vesicles, 2020
Goren Saenz-Pipaon, Patxi San Martín, Núria Planell, Alberto Maillo, Susana Ravassa, Amaia Vilas-Zornoza, Esther Martinez-Aguilar, José Antonio Rodriguez, Daniel Alameda, David Lara-Astiaso, Felipe Prosper, José Antonio Paramo, Josune Orbe, David Gomez-Cabrero, Carmen Roncal
RNA-Seq was performed in EVs (details are provided in Supplemental Methods) from controls, PAD patients with intermittent claudication (IC, Fontaine class IIa) and PAD patients with critical limb ischaemia (CLI, Fontaine class IV) with myocardial infarction in the follow-up study (n = 12/group). The protocol was adapted from Jaitin et al., 2014 (MARS-Seq) [16]. Briefly, 50 µL of isolated EVs were mixed with 50 µL of Lysis/Binding Buffer (Invitrogen). Poly-A RNA was captured with Dynabeads Oligo (dT) (Invitrogen) and reverse-transcribed with AffinityScript Multiple Temperature Reverse Transcriptase (Agilent) using oligo (dT) primers carrying a 7 bp index. Up to eight samples with similar overall RNA content were pooled together and subjected to linear amplification by in vitro transcription using a HiScribe T7 High Yield RNA Synthesis Kit (New England Biolabs). Amplified RNA was fragmented into 250–350 bp with RNA Fragmentation Reagents (Invitrogen) and dephosphorylated with thermosensitive alkaline phosphatase (FastAP, Thermo). Partial Illumina adaptor sequences [16] were ligated with T4 RNA Ligase 1 (New England Biolabs), followed by a second reverse transcription reaction. Full Illumina adaptor sequences were added with KAPA HiFi DNA Polymerase (Kapa Biosystems). Libraries were sequenced in an Illumina NextSeq 500 at a sequence depth of 10 million reads per sample. All RNA-Seq data have been submitted to NCBI GEO repository, study number GSE140320.