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Really interesting question: The lethal yellow mutation (also abbreviated Ay) affects the agouti signalling protein which plays a major role in pigmentation. Heterozygous expression of it leads to the dominant expression of pheomelanin (which is yellow), causing the mice to express this color (among other effects). To understand why it is homozygous ...


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A methylated nucleotide is the same nucleotide, for the purposes of base-pairing events. The methylated base will be paired with its Watson-Crick opposite after replication, for instance (and methylation will even persist after replication).


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Gene expression can be very well described by Hill functions, i.e.: $$c_Y(c_X) = \frac{c_X^n}{1+c_X^n}$$ when $X$ activates $Y$ and $$c_Y(c_X) = \frac{1}{1+c_X^n}$$ when $X$ represses $Y$ (omitting units and all sorts of constants for simplicity). For the common case that $n>1$, these functions look like this: As you can see, they are far from linear, ...


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Your question is very broad, but I'll try to address each of your points briefly. It would be nearly impossible to edit the genes in every cell of a human being or other complex organism simply due to the number (and accessibility) of cells. A full-grown human has in the neighborhood of 30 trillion cells - 30,000,000,000,000. Cells in locations such as the ...


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What is Protein Expression Level? This was the original title of the post, which I edited myself because I regard the answer as trivial, but the question as more substantial. To deal with the trivial first: ‘Level’ is not a scientific unit, and can only be used unambiguously as a scientific term in its English sense in relation to liquids, e.g. “The level ...


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Yes, Agrobacterium is indeed a very widely used vector in plants. So it wouldn't be wrong to consider bacteria as vectors. Just to add, it's worth noting that in recent times, bacterial vector options have been explored in the case of humans also, especially in the case of gene therapy for cancer treatment, though its success hasn't been demonstrated yet. ...


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The answer to your general question is 'it depends': A lot of RNA localisation to the ER and mitochondria happens co-translationally (based on the protein targeting sequences), so these mRNA actually depend on translation to be localised. However, RNA localisation to mitochondria can also happen due to targeting sequences in the mRNA 3'UTR - in these cases ...


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There are technologies available for inducing higher (or lower) gene expression in cultured mammalian/human cells as well as in bacteria. The state of the art is CRISPR-mediated gene activation/repression, where you fuse a transcription activation domain to a Cas gene in a CRISPR-Cas system (usually Cas9), and provide a guide RNA to target genes of interest. ...


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First, it's been estimated that the narrow-sense heritability of facial morphology is about ~60-90% (Martinez-Abadias et al 2009, Weinberg et al 2013, Liu et al 2012), so genetics is likely to be a greater influence than environment. But actually, the molecular genetic understanding of cranio-facial morphology is quite poor relative to other quantitative ...


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Heterogeneity is a noun meaning: the fact of consisting of parts or things that are very different from each other In scientific use the context determines what is differing. The context here is gene expression in individual embryonic stem cells (presumably single-cell RNASeq). Here the heterogeneity in expression would be for the genes …(Neurod1, Klf4, ...


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Just to expand on @Wrzlprmft's great answer with a concrete example: Sticking to your simple gene circuit with $X$, $Y$, and $Z$, now consider the possibility that $Y$ also activates its own expression via a positive feedback loop: $X \to \underset{\circlearrowright}Y \to Z$ Here activation of $Y$ will be only minimally dependent on $X$. Once $Y$ is ...


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$\gamma$-irradiation produces single- and double-strand DNA breaks, depending on the dosage, and activates DNA damage repair pathways like p53. During this time, the cell cycle arrests and most if not all mRNA production ceases. For sub-lethal doses of $\gamma$ rays, I would expect to see newly-produced mRNA levels drop off fairly quickly with time following ...


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I lack the knowledge to fully answer your question but I can give some potentially useful pieces of information: In theory you can easily in-silico reverse translate a peptide sequence to an unambiguous nucleotide sequence using the GMOs optimized codon usage. I can share a Python script for that. Also you could easily search for the 'real' nucleotide ...


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Yes, Sodium phenylbutyrate can upregulate the transcription of silenced genes by inhibiting the activity of Histone deacetylases (HDACs). Histone acetylation performed by Histone acetyltransferases (HATs) helps in activation of genes, while deacetylation performed by HDACs is responsible for gene silencing. This makes HDACs a potent drug target to treat ...


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A sequence is executed with transcriptase. To double amount of signaling or some protein production try doubling the sequence occurrence.


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If you are after large amounts of a particular protein, search "recombinant protein production". It is a huge field.


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Agrobacterium tumefaciens and Agrobacterium rhizogenes are soil-based plant pathogenic bacterial strains containing plasmid. This plasmid is known as Ti plasmid and is responsible for inducing tumor. Part of this plasmid called T-DNA can be integrated into the host chromosomes. So, this bacterium plasmid act as vector, but not the whole bacterial cell. (...


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The Methylation will change the individual nucleotide(s) and persist after replication. However the order of the base pairs does not change, so the information in the DNA will still remain , and the base pairs remain with their same partners.For an analogy consider a hardcover book as the DNA . Then the author of the book signs the cover. The signature is ...


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In the context of transcriptomics the term 'enrichment' is usually connected to differential analysis: If a transcript (or some/all transcripts of a gene) are detected in a given sample that transcript is expressed If a transcript is detected at (statistically significant) higher levels in sample (or condition) A compared to another sample B, that ...


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In most cases (i.e. assuming there is no aneuploidy) a gene won't be enriched, however, the transcript from a gene may be enriched. A synonym in this case would be overrepresented. In other words, you find relatively more of the transcript compared to other transcripts. Since you seem to confused about the difference between transcripts and genes, I highly ...


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It depends on the definition of housekeeping genes. ENCODE recently released RNA-seq of 17 tissues at 8 developmental stages. A list of housekeeping genes was also provided. They are not exactly constant. They just are less variable than other genes.


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