China
Africa
Explore chapters and articles related to this topic
Alternative splicing of arsenic (III oxidation state) methyltransferase
Published in Yong-Guan Zhu, Huaming Guo, Prosun Bhattacharya, Jochen Bundschuh, Arslan Ahmad, Ravi Naidu, Environmental Arsenic in a Changing World, 2019
Alternative splicing generates more than two mRNAs by alteration in the location and combination at the splicing sites, resulting in variant isoforms of the protein translated from a single gene. Environmental chemicals that are known to cause oxidative stress, such as paraquat and arsenic, were shown to impair control over mRNA splicing, resulting in the deregulation of the survival of motor neurons (SMN) and the induction of DNA damage in gene 45α (GADD45α). It has been reported that hydrogen peroxide (H2O2) stimulates alternative splicing of hypoxanthine guanine phosphoribosyl transferase (HPRT) and soluble guanylyl cyclase (sGC). Thus, it is apparent that oxidative stress causes splicing abnormalities on specific mRNAs. However, it remains unknown whether the control of splicing of AS3MT mRNA is vulnerable to oxidative stress.
Biomolecular Processing and Molecular Electronics
Published in Sergey Edward Lyshevski, Molecular Electronics, Circuits, and Processing Platforms, 2018
In nucleic acids, monomers are four types of nucleotides that differ in their nitrogenous bases. Genes are typically hundreds or thousands nucleotides long, and each gene has a specific sequence of nitrogenous bases. A protein also has monomers arranged in a particular linear order, but its monomers consist of 20 amino acids. Transcription and translation processes (steps) are involved: Transcription is the synthesis of RNA under the direction of DNA. Agene’fs unique sequence ofDNAnucleotides provides a template for assembling a unique sequence of RNA nucleotides. The resulting RNA molecule (called the messenger RNA and denoted as mRNA) is a transcript of the gene’s protein-building instructions. Thus, the function of mRNA is to transcript a genetic code from the DNA to the protein-synthesis machinery of the cell. Translation is the synthesis of a polypeptide that occurs under the direction of mRNA. The cell must translate the base sequence of an mRNA molecule into the amino acid sequence of a polypeptide. The sites of translation are ribosomes, with many enzymes and other agents facilitating the orderly linking of amino acids into polypeptide chains. The sequence chain is: DNA → RNA → protein.
Genes and Genomics
Published in Firdos Alam Khan, Biotechnology Fundamentals, 2020
mRNA is involved in protein synthesis by carrying coded information to the sites of protein synthesis: the ribosomes. Here, the nucleic acid polymer is translated into a polymer of amino acids: a protein. In mRNA, as in DNA, genetic information is encoded in the sequence of nucleotides arranged into codons consisting of three bases each. Each codon encodes for a specific amino acid, except the stop codons that terminate protein synthesis. This process requires two other types of RNA: transfer RNA (tRNA), which mediates recognition of the codon and provides the corresponding amino acid, and ribosomal RNA (rRNA), which is the central component of the ribosome’s protein manufacturing machinery.
It's not just about protein turnover: the role of ribosomal biogenesis and satellite cells in the regulation of skeletal muscle hypertrophy
Published in European Journal of Sport Science, 2019
Matthew Stewart Brook, Daniel James Wilkinson, Ken Smith, Philip James Atherton
Protein synthesis is the process by which ribosomes create polypeptide chains through linking amino acids together in a specific order according to mRNA. As such, rates of protein synthesis can be modulated by the rate of mRNA translation, known as “translational efficiency”. A primary control point regulating translational efficiency and therefore protein synthesis in the majority of eukaryotic cells is by cap dependent translation. This involves the assembly of many eukaryotic initiation factors (eIF's) to form a preinitiation complex (PIC) that interacts with the 5′ end of an mRNA to instigate protein synthesis (for more detail readers are directed to [Jackson, Hellen, & Pestova, 2010]). However, with protein synthesis being an energy demanding processes (e.g. through peptide bonding) it is unsurprising that there is myriad of regulating signaling cascades, many of which culminate on the mammalian target of rapamycin (mTOR), that integrates signals such as exercise, AA availability and energy status to coordinate cellular metabolism (Goodman et al., 2011). Some of the best understood targets of mTOR are those directly involved in cap-dependent translation, including P70S6K1, 4E-BP1, and RPS6 that can enhance translation initiation and efficiency in the absence of ribosomal biogenesis (Chesley, MacDougall, Tarnopolsky, Atkinson, & Smith, 1992).
Variance-constrained filtering for discrete-time genetic regulatory networks with state delay and random measurement delay
Published in International Journal of Systems Science, 2019
Dongyan Chen, Weilu Chen, Jun Hu, Hongjian Liu
It is well known that the process of cell division involves a large number of substances, such as messenger RNA (mRNA), proteins and other small molecules. The process of gene expression from genes to proteins is mainly composed of transcription and translation (Chen & Aihara, 2002; Chen, Chen, Hu, Liang, & Dobaie, 2018). During transcription, mRNAs are synthesised from genes through the regulation of transcription factors (proteins). In translation, nucleotide sequences in mRNAs are used to synthesise proteins (Vembarasan, Nagamani, Balasubramaniam, & Park, 2013; Wan, Wang, Wu, & Liu, 2018a). The mechanisms of regulating the gene expression are called the GRNs, which are actually biochemically dynamical systems. Over the past two decades, the GRNs have gained a lot of research attention in the field of biological and biomedical sciences. A variety of models have been presented to describe the GRNs, such as the Boolean model (Somogyi & Sniegoski, 1996), the differential equation model (Smolen, Baxter, & Byrne, 2000), the Bayesian model (Friedman, Linial, Nachman, & Pe'er, 2000) and the state-space model (Wu, Zhang, & Kusalik, 2004). As we know, owing to the slow reaction processes of transcription, translation and the finite switching speed of the amplifier, the time-delay is inevitable in the GRNs (Wan, Wang, Han, & Wu, 2018; Zhang, Wu, & Cui, 2015). So far, a great number of analysis and synthesis issues for delayed GRNs have been investigated, such as stability analysis (Tu & Lu, 2006; Wan, Xu, Fang, & Yang, 2014; Wang, Wang, Nguang, Zhong, & Liu, 2016) and synchronisation problems (Jiang, Liu, Yu, & Shen, 2015; Yue et al., 2017). To be specific, some methods have been provided in Chen Aihara (2002) to analyse the local stability of GRNs with time-invariant delay. In Wang et al. (2016), the stability analysis problem has been studied for a class of GRNs with parameter uncertainties and time-varying delays, where some sufficient criteria have been presented to guarantee the robust asymptotic stability of the GRNs by using Jensen inequality and convex combination approach. In addition, the finite-time synchronisation problem has been considered in Jiang et al. (2015) for stochastic GRNs, and sufficient conditions have been given to ensure that the designed controller can synchronise the concentrations of gene products (i.e. mRNAs and proteins) under the finite-time criterion.