China
Africa
Explore chapters and articles related to this topic
Morphology, Pathogenesis, Genome Organization, and Replication of Coronavirus (COVID-19)
Published in Hanadi Talal Ahmedah, Muhammad Riaz, Sagheer Ahmed, Marius Alexandru Moga, The Covid-19 Pandemic, 2023
Sadia Javed, Bahzad Ahmad Farhan, Maria Shabbir, Areeba Tahseen, Hanadi Talal Ahmedah, Marius Moga
Therefore, after the entrance of SARS-COVID-2 into the body, the next step is viral replication. In order to bind to their mobile receptors, CoVs use homotrimer spike glycoprotein (including S1 in each spike monomer and S2 in each subunit) on the envelope. In the event of cell entry, such a bond triggers a subsequent cascade that leads to cell-viral membrane fusion [101]. In Coronavirus, there are six ORF regions that act as models by which sub-genomic mRNA structures the protein, spike, nucleocapsid, and diaphragm-proteins. The polypeptides derived from pp1a and pp1ab are generated by ORFs [102].
The Potential of Microbial Mediated Fermentation Products of Herbal Material in Anti-Aging Cosmetics
Published in Namrita Lall, Medicinal Plants for Cosmetics, Health and Diseases, 2022
Type III collagen comprises approximately 20% of the total collagen in the skin, concentrated in the mesh-like papillary dermis, while the remaining 80% is comprised of type-I collagen, concentrated in the reticular dermis. Structurally, type III collagen is a homotrimer of α1(III) chains and type I, a heterotrimer of two α1(I) chains and one α2(I) chain arranged in an anti-parallel conformation to produce more dense fibers (Cole et al., 2018). These fibers are enzymatically cross linked following the secretion of procollagen and its maturation to confer resistance to proteolytic cleavage. The proteolytic removal of C and N terminal pro-peptides facilitates the maturation of procollagen into mature collagen fibers. For instance, in type-I collagen various intracellular lysine residues containing α1(I) and α2(I) chains are converted to hydroxylysine through the action of lysyl hydroxylase, while extracellular lysine and hydroxylysine residues are converted to aldehydes through the action of lysyl oxidase. This process enables spontaneous, non-reducible inter- and intra-peptide crosslinking. The action of lysyl oxidase is crucial in facilitating matrix deposition of elastin fibers and prevention of excessive elasticity (Cole et al., 2018).
Order Bunyavirales
Published in Paul Pumpens, Peter Pushko, Philippe Le Mercier, Virus-Like Particles, 2022
Paul Pumpens, Peter Pushko, Philippe Le Mercier
The expression of Gn and Gc envelope glycoproteins of Andes orthohantavirus (ANDV) and PUUV in mammalian 293FT cells led to their self-assembly into pleomorphic VLPs, which did not require the protein N and were released to cell supernatants (Acuña et al. 2014). Moreover, a Gc endodomain deletion mutant did not abrogate VLP formation (Acuña et al. 2014), while acidification triggered rearrangement of Gc into a stable post-fusion homotrimer (Acuña et al. 2015).
Spatial composition and turnover of the main molecules in the adult glomerular basement membrane
Published in Tissue Barriers, 2023
David W. Smith, Azin Azadi, Chang-Joon Lee, Bruce S. Gardiner
There is information on the amount of HS attached to the proteoglycans, though these data are mainly from chicks, with some human data for perlecan. Chick brain agrin core protein is about 220 kDa, while the intact agrin proteoglycan is reported to be in excess of 400 kDa.48 We estimate that about 200 kDa of HS is attached to intact GBM agrin. Human perlecan core protein is reported to be 467 kDa, while intact perlecan has 3 HS side chains and possibly a chondroitin sulfate side chain, with a total weight of up to 750 kDa.49 Intact GBM perlecan has about 200 kDa of HS attached to it.49 We base this estimate on the following. For the collagen XVIII found in the chick embryo, it is reported the collagen XVIII ‘core chain protein’ is 180 kDa, which has 120 kDa of HS attached to it.50 We treble values for the core chain protein of collagen XVIII to approximately estimate a value for the homotrimer of intact collagen XVIII (i.e., we assume 300 kDa of HS is attached to collagen XVIII).
Potential mechanisms of Pyrrosiae Folium in treating prostate cancer based on network pharmacology and molecular docking
Published in Drug Development and Industrial Pharmacy, 2022
Wen-Hua Guo, Kun Zhang, Lu-Hong Yang
TNF, JUN, IL6, IL1B, CXCL8, RELA, CCL2, TP53, IL10, and FOS were identified as the 10 hub targets genes related to PCa. Seven of these hub genes were classified into the TNF signaling pathway (Figure 9). As a critical cytokine, TNF can induce a wide range of intracellular signal pathways including apoptosis and cell survival as well as inflammation and immunity [39–41]. Activated TNF (homotrimer) binds to its receptors (TNFR1, TNFR2), and mediates the association of some adaptor proteins such as TRADD or TRAF2, which in turn initiate recruitment of signal transducers [42–44]. Therein, the seven hub genes play important roles in leukocyte recruitment, inflammatory cytokines, transcription factors, and cell survival by activating NF-κB pathway, MAPK cascade, or PI3K-dependent NF-κB pathway, etc. It shows that PF is involved in the regulation of PCa growth by targeting hub genes and participating in the TNF signaling pathways.
Emerging Human Coronavirus Infections (SARS, MERS, and COVID-19): Where They Are Leading Us
Published in International Reviews of Immunology, 2021
The S protein is a class 1 fusion protein, which promotes attachment and fusion of the viral and cellular membrane to facilitate the virus entry in the cell [197]. Hence S protein determines the host range and cell tropism. The S protein is a homotrimer comprising of 3 protomers, each comprises of single polypeptide chain of 1100–1600 residues, depending on the CoV species [57]. For many CoVs, the S protein is cleaved into S1 and S2 functional units by host cell proteases, which remain non-covalently bound in the prefusion conformation [197]. Also, the core structures of MERS-CoV and SARS-CoV S1-CTDs are similar to each other, whereas their receptor binding motifs (RBMs) are markedly different [198]. For example, SARS-CoV RBM is a loop-dominated gentle concave surface, whereas MERS-CoV RBM has a four-stranded antiparallel β-sheet to provide a relatively flat surface for DPP4 binding [198]. Like, SARS-CoV RBM, the SARS-CoV-2 RBM forms a gently concave surface with a ridge on one side, which binds to the exposed outer surface of the claw-like structure of ACE2 [43]. The binding interface of SARS-CoV2 RBM is bigger than the SARS-CoV RBM and covers more ACE2 surface. The conservation of glycan interacting arginine between SARS-CoV and SARS-CoV2 in their ACE2 binding cites shows a close evolutionary relationship between two viruses [43].