Virus structure
Advances in microscopy and scientific techniques have led to a better classification of viruses and their properties. Electron microscopy has allowed us to visualize viruses in great detail, while molecular and cellular assays have broadened our understanding of how viruses function and are related to one another (Jennifer Louten, 2016).
Researchers employed scintillation spectroscopy and electron microscopy techniques to detect modifications in viral genomes and proteins. Electron microscopy techniques are used to find the location and orientation of capsid protein residues (Krista Rule Wigginton, and Tamar Kohn, 2012).
Virus surrounds its nucleic acid with a protein shell, called the capsid. The capsid is composed of one or more different types of proteins that repeat over and over again.
Most viruses also have an envelope surrounding the capsid. The envelope is a lipid membrane that is derived from one of the cell’s membranes.
Viruses’ genetic material can be composed of DNA or RNA (but not both). Virus can have single-stranded DNA, single-stranded RNA, and double-stranded RNA.
The virus genetic material encodes the instructions for the proteins that will spontaneously assemble into the new viruses.
Viruses are completely dependent upon the internal environment of the cell to create new virus.
All viruses bind to the receptor (virus receptor is a host surface component that participates in virus binding and facilitates viral infection) on the surface of a cell to gain entry into the cell. Virus binding was previously considered to involve simple recognition and attachment to a single cell surface molecule by virus attachment proteins (Anne M. Haywood, 1994).
REFERENCES
. Anne M. Haywood (1994). Virus Receptors: Binding, Adhesion Strengthening, and Changes in Viral Structure. Journal of Virology, No 1.
. Jennifer Louten (2016). Virus Structure and Classification. Essential Human Virology.
. Krista Rule Wigginton, Tamar Kohn (2012). Virus disinfection mechanisms: the role of virus composition, structure, and function. Virology, No 2.
Gene therapy tiny review
Gene therapy medicinal product is a biological medicinal product. This product aims to regulate, repair, replace, add or delete a genetic sequence. Gene transfer vectors which are now producing clinical results. In September 14th 1990 the FDA approved the first time a gene therapy trial with a therapeutic attempt in humans. Two children suffering from adenosine deaminase deficiency (ADA-SCID). From the data was published in 2013, more than 1700 gene therapy medicinal products approved clinical trials (Thomas et al., 2013).
Epigenetics refers to reversible heritable mechanisms, which can affect gene expression without underlying changes in DNA sequences, but rather via chromatin modifications. The loss of histones during cellular aging is one of the key observations from simple eukaryotic models, including yeast, to mice and humans (Dominik et al., 2021).
For the in vivo application of gene-based drugs, the therapeutic gene is introduced directly into the body (e.g. muscle, liver) of the patient, while for ex vivo applications, patient cells are first isolated from the body, genetically modified outside the body and reintroduced into the patient as an autologous transplant (Kerstin et al., 2013)
The knowledge gained within the field over the past several decades provides much hope for the future of gene therapy. The success of gene therapy has largely been driven by improvements in non-viral and viral gene transfer vectors. An array of physical and chemical non-viral methods have been used to transfer DNA and mRNA (Keeler et al., 2017).
From the review of Kerstin et al., (2013), the risks associated with gene therapy are already being successfully addressed.
From the review of Gantenbein et al (2020), viral delivery poses significant safety concerns such as inefficient/unpredictable reprogramming outcomes, genomic integration, as well as unwarranted immune responses and toxicity. The risks and the acceptance of viral gene transfer methods experienced have been affected by sudden patient deaths, such as the examples of Jesse Gelsinger and Joli Mohr (Wilson, 2009; Yarborough and Sharp, 2009). The advantages of non-viral gene therapy are the fact that the effects are not long- lived.
REFERENCES
. Dominik Saul and Robyn Laura Kosinsky, 2021. Epigenetics of Aging and Aging Associated Diseases, International journal of molecular science, 22. Doi: 10.3390/ijms22010401.
. Gantenbein Benjamin, Shirley Tang, Julien Guerrero, Natalia Higuita-Castro, Ana I. Salazar-Puerta, Andreas S. Croft, Amiq Gazdhar and Devina Purmessur, 2020. Non-viral Gene Delivery Methods for Bone and Joints, Frontiers in Bioengineering and Biotechnology, 8. Doi: 10.3389fbioe.2020.598466.
. Jung-Won Shin, Soon-Hyo Kwon, Ji-Young Choi, Jung-Im Na, Chang-Hun Huh, Hye-Ryung Choi and Kyung-Chan Park, 2019. Molecular Mechanisms of Dermal Aging and Antiaging Approaches, International journal of molecular science, 20. Doi:10.3390/ijms20092126.
. Keeler, ElMallah and Flotte, 2017. Gene Therapy 2017: Progress and Future Directions, Clin Transl Sci 10: 242–248. Doi:10.1111/cts.12466.
. Kerstin B. Kaufmann, Hildegard Buning, Anne Galy, Axel Schambach, Manuel Grez, 2013. Gene therapy on the move, EMBO Mol Med, 5: 1642–1661. Doi: 10.1002/emmm.201202287.
. Thomas Wirth, Nigel Parker, Seppo Ylä-Herttuala, 2013. History of gene therapy, Gene, 525: 162–169.
Plant–fungus tiny review
Plant health and productivity significantly depend on microbial activity in the rhizosphere and on the microbes directly interacting with the plant (Susanne Zeilinger et al., 2016). Plant pathogens account for annual losses of about 15% of global crop production, and fungi have the potential to destroy enough food to feed up to around 60% of the world’s population (Lauren M. Segal1 and Richard A. Wilson, 2017).
A variety of compounds contributing to plant–fungal communication is released by plant roots into their surroundings, i.e. the rhizosphere. The recognition of appropriate plant hosts is among the most critical steps in the interaction of fungi with plants (Susanne Zeilinger et al., 2016).
Soon after coming into contact with a plant, fungal pathogens are likely to be detected by the plant and confronted with an active defense system. Successful pathogens, in turn, need to neutralize the plant resistance strategy. Plants may recognize an aggressor through factors that are present on the fungal surface. After recognition of the pathogen, a multitude of plant resistance-associated reactions is initiated (Wolfgang Knogge, 1996).
Plants are able to respond to pathogen attack quickly through the induction of various defense mechanisms (Matthias Hahn and Kurt Mendgenv, 2001). MiRNA constitute a major class of small non-coding, endogenous RNAs, which have been recently reported to be the key components of complex network of gene regulatory pathway. MiRNA play extensive role in regulating the key components of hormonal signaling pathway. RNA directed DNA methylation (RdDM) is an epigenetic control mechanism driven by a subset of siRNAs (Om Prakash Gupta, 2014).
REFERENCES
. Matthias Hahn and Kurt Mendgenv, 2001. Signal and nutrient exchange at biotrophic plant–fungus interfaces. Current Opinion in Plant Biology, 4:322–327.
. Om Prakash Gupta, Pradeep Sharma, Raj Kumar Gupta, Indu Sharma, 2014. Current status on role of miRNAs during plant fungus interaction. Physiological and Molecular Plant Pathology. Vol. 85: 1-7 .Doi: 10.1016/j.pmpp.2013.10.002.
. Susanne Zeilinger, Vijai K. Gupta, Tanya E. S. Dahms, Roberto N. Silva, Harikesh B. Singh, Ram S. Upadhyay, Eriston Vieira Gomes, Clement Kin-Ming Tsui and Chandra Nayak S, 2016. Friends or foes? Emerging insights from fungal interactions with plants.FEMS Microbiology Reviews, 40: 182–207. Doi: 10.1093/femsre/fuv045.
. Wolfgang Knogge (1996). Funga Infection of Plants. The Plant Cell, Vol. 8, 1711-1722.