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This is a useful open access article:
The DNA fibre technique – tracking helicases at work – ScienceDirect
Answer by Microsoft Copilot
Exosomes are small extracellular vesicles that play a significant role in cell-to-cell communication by transporting proteins, lipids, and nucleic acids between cells. Their potential in treating various diseases is a rapidly growing area of research. Here’s a breakdown of their applications and the current state of knowledge:
Applications of Exosomes in Disease Treatment
1. Cancer Therapy:
– Drug Delivery: Exosomes can be engineered to deliver anti-cancer drugs directly to tumor cells, improving the efficacy and reducing side effects¹.
– Cancer Vaccines: Exosomes derived from dendritic cells can stimulate the immune system to target cancer cells².2. Neurodegenerative Diseases:
– Neuroprotection: Exosomes from stem cells have shown potential in protecting neurons and promoting regeneration in conditions like Alzheimer’s and Parkinson’s diseases³.3. Cardiovascular Diseases:
– Tissue Repair: Exosomes from stem cells can aid in repairing damaged heart tissue after a heart attack³.4. Inflammatory and Autoimmune Diseases:
– Modulating Immune Response: Exosomes can carry anti-inflammatory molecules to reduce inflammation in diseases like rheumatoid arthritis².5. Chronic Degenerative Diseases:
– Regenerative Medicine: Exosomes are being explored for their ability to promote tissue repair and regeneration in conditions like osteoarthritis⁴.Fact vs. Fiction
– Fact: The therapeutic potential of exosomes is supported by numerous preclinical studies and early-phase clinical trials. They have shown promise in delivering drugs, modulating immune responses, and promoting tissue repair¹²³.
– Fiction: While the potential is significant, exosome-based therapies are still largely experimental. Many claims about their effectiveness are based on early-stage research, and more extensive clinical trials are needed to confirm their safety and efficacy².In summary, exosomes hold great promise for treating a variety of diseases, but their use in clinical practice is still in the early stages. Ongoing research and clinical trials will determine how these therapies can be effectively and safely implemented.
References
(1) Exosomes: a review of biologic function, diagnostic and targeted …. https://jbiomedsci.biomedcentral.com/articles/10.1186/s12929-024-01055-0.
(2) A review on exosomes application in clinical trials: perspective …. https://biosignaling.biomedcentral.com/articles/10.1186/s12964-022-00959-4.
(3) Exosomes as therapeutic and drug delivery vehicle for neurodegenerative …. https://jnanobiotechnology.biomedcentral.com/articles/10.1186/s12951-024-02681-4.
(4) Exosomes | Treatments | Infusio.org. https://www.infusio.org/TREATMENTS/EXOSOME-THERAPY/.Gene sharing and protein moonlighting are related concepts that describe multifunctional proteins:
- Gene Sharing:
- Definition: Gene sharing refers to a phenomenon where a single gene encodes a protein that performs more than one function.
- Mechanism: Unlike alternative RNA splicing, DNA rearrangement, or post-translational processing (which generate different proteins from a single gene), gene sharing allows a single gene to maintain multiple distinct functions without duplicating itself.
- Examples: Crystallins are well-studied examples of gene sharing. These proteins function as enzymes in various tissues but form densely packed lenses in the eye when expressed at high levels.
- Protein Moonlighting:
- Definition: Protein moonlighting refers to the ability of a single protein to perform multiple functions, often beyond its primary enzymatic role.
- Evolution: Ancestral moonlighting proteins originally had a single function but acquired additional functions through evolution.
- Functions: Moonlighting proteins can participate in signal transduction, transcriptional regulation, apoptosis, motility, and structural roles.
- Difference: Unlike multifunctional proteins with distinct domains, moonlighting proteins maintain their primary function while gaining secondary non-enzymatic roles.
- Detection: Unexpected protein locations within cells or sequence/structure homology can hint at moonlighting functions.
In summary, gene sharing involves a single gene encoding a multifunctional protein, while protein moonlighting describes a protein performing multiple roles beyond its primary enzymatic function.
Argonaute proteins are a family of proteins found in many organisms that play a crucial role in the process of RNA interference (RNAi). RNAi is a way for cells to regulate gene expression by silencing genes.
What Argonaute proteins do:
1. Bind small non-coding RNAs: Argonaute proteins bind to different classes of small non-coding RNAs, including microRNAs (miRNAs), small interfering RNAs (siRNAs), and Piwi-interacting RNAs (piRNAs). These small RNAs act like guides, directing the Argonaute protein to a specific target mRNA molecule.
2. Form RNA-induced silencing complex (RISC): Once an Argonaute protein binds to a small RNA, it forms a complex called the RNA-induced silencing complex (RISC). RISC is the machinery that carries out RNAi.
3. Silence target mRNA: The RISC complex uses the small RNA guide to find a complementary target mRNA molecule. Once the target mRNA is found, the Argonaute protein can either cleave the mRNA molecule in half, or it can block the mRNA molecule from being translated into protein.By silencing target mRNAs, Argonaute proteins help to regulate gene expression in a variety of cellular processes, including development, differentiation, and immunity. They are also being investigated as potential therapeutic targets for a variety of diseases.
Pharmacogenetics is the branch of pharmacology concerned with the effect of genetic factors on reactions to drugs.
Pharmacogenomics is the branch of genetics concerned with the way in which an individual’s genetic attributes affect the likely response to therapeutic drugs.
Source:
https://bioinformaticshub.net/general/bioinformatics-terms-glossary/
The answer you need may be found in this post:
How To Better Treat Cancer: Cancer Omics – Bioinformatics Hub
I have got this answer by Hammad Rana on Quora.com:
DNA replication-related template switching is a process where the copying of genetic information involves temporarily changing the template (the strand used as a guide) during replication. In simpler terms, when cells make new copies of their DNA, sometimes they switch the strand they’re copying from.
Imagine you have a zipper with two sides, and you want to make an exact copy of it. In the DNA replication process, enzymes unzip the DNA double helix, just like opening the zipper. Now, to make a new zipper, you need a template. Usually, one side of the unzipped DNA acts as the template for the new copy.
But here’s where template switching comes in. Occasionally, during replication, the copying process might switch from one side to the other, like if you started copying from the left side of the zipper and then switched to the right side for a little bit. This switching can happen for various reasons, including the presence of certain DNA structures or obstacles.
In the end, you end up with a new DNA strand that has information from both sides of the original DNA, kind of like a zipper made from both the left and right sides. Template switching is a normal part of the DNA replication process and contributes to genetic diversity.
I received this invitation by email:
Comprehensive Quality Control and Interactive Analysis of Single Cell RNA-seq Data. In this webinar, Joshua Campbell will talk about the fundamentals of scRNA-seq analysis and how to handle various challenges.
In intestinal mucosal cells, an RNA editing complex alters one base in ApoB-100 mRNA (C is deaminated and converted to U), producing a stop codon. This leads to production of a protein that is only 48% of the original protein, the ApoB-48 of chylomicrons.
Deamination of adenine (A) in tRNA produces inosine (I), which helps identifying more than one codon (degeneracy of the code).
RNA-editing events may regulate cancer development and metabolic dysfunctions.
You probably mean mitochondrial DNA (mtDNA).
It is not “empty DNA”. It is “em-tee-DNA”.
With a few exceptions, animals have 37 genes in their mitochondrial DNA: 13 for proteins, 22 for tRNAs, and 2 for rRNAs (Mitochondrial DNA – Wikipedia).
The exclusome is a newly discovered cytoplasmic organelle in mammalian cells. The first publication about it was in September 2023 in Molecular Biology of the Cell:
A dedicated cytoplasmic container collects extrachromosomal DNA away from the mammalian nucleus.
Exclusome membrane is from endoplasmic reticulum and nuclear membrane. Circular DNA inside is foreign DNA and telomeric DNA from the nucleus.
On the other hand, exosomes are membranous nanovesicles of endocytic origin released by most cell types from diverse organisms. Exosomes are present in many and perhaps all biological fluids, including blood, urine, and cultured medium of cell cultures.
Instead of performing one reaction per well, dPCR involves partitioning the PCR solution into tens of thousands of nano-liter sized droplets, where a separate PCR reaction takes place in each one. The partitioning of the sample allows one to estimate the number of different molecules by assuming that the molecule population follows the Poisson distribution, thus accounting for the possibility of multiple target molecules inhabiting a single droplet.
dPCR measures the actual number of molecules (target DNA) as each molecule is in one droplet, thus making it a discrete “digital” measurement. It provides absolute quantification because dPCR measures the positive fraction of samples, which is the number of droplets that are fluorescing due to proper amplification. This positive fraction accurately indicates the initial amount of template nucleic acid. Similarly, qPCR utilizes fluorescence; however, it measures the intensity of fluorescence at specific times (generally after every amplification cycle) to determine the relative amount of target molecule (DNA), but cannot specify the exact amount without constructing a standard curve using different amounts of a defined standard. It gives the threshold per cycle (CT) and the difference in CT is used to calculate the amount of initial nucleic acid. As such, qPCR is an analog measurement, which may not be as precise due to the extrapolation required to attain a measurement.
dPCR measures the amount of DNA after amplification is complete and then determines the fraction of replicates. This is representative of an endpoint measurement as it requires the observation of the data after the experiment is completed. In contrast, qPCR records the relative fluorescence of the DNA at specific points during the amplification process, which requires stops in the experimental process. This “real-time” aspect of qPCR may theoretically affect results due to the stopping of the experiment. In practice, however, most qPCR thermal cyclers read each sample’s fluorescence very quickly at the end of the annealing/extension step before proceeding to the next melting step, meaning this hypothetical concern is not actually relevant or applicable for the vast majority of researchers. dPCR measures the amplification by measuring the products of end point PCR cycling and is therefore less susceptible to the artifacts arising from impaired amplification efficiencies due to the presence of PCR inhibitors or primer template mismatch.
qPCR is unable to distinguish differences in gene expression or copy number variations that are smaller than twofold. On the other hand, dPCR has a higher precision and has been shown to detect differences of less than 30% in gene expression, distinguish between copy number variations that differ by only 1 copy, and identify alleles that occur at frequencies less than 0.1%.
Source: Digital polymerase chain reaction – Wikipedia
I received this from Medscape medical news:
Genetic Profiles Affect Smokers’ Lung Cancer Risk (medscape.com)
- Gene Sharing:
