User:Dananguyen/sandbox

Week 3: Article Evaluation

Article: Molecular Genetics
 * Everything in the article is relevant or related to the article topic
 * The article appears very neutral with nothing that seems heavily biased
 * Very general information, not very detailed and not much information
 * Some info not cited, not many citations overall - despite this being a rather important and widespread topic
 * Citation used were from reliable and unbiased sources
 * Article is rated as start-class and top-importance
 * Link citations work and sources support claims in article
 * Conversations on talk page highlight grammatical/spelling errors, clarifying confusing wording and various citation comments
 * Wikipedia page discusses it very generally, in less detail than we've talked about in class
 * Many more uses and fields within molecular genetics that were not discussed in the article - such as computational and systems biology, functional genomics and proteomics
 * Introduction could be improved on - currently a very general description of molecular genetics, not very detailed and not much insight to it
 * Gene therapy section could be expanded upon to include efficacy of treatment, any ethical concerns and diseases it has been successful in treatment of

Good job. Keep it up! AdamCF87 (talk) 17:42, 5 October 2017 (UTC)

Week 4: Add to an Article

Added 2 sentences and citation to Barr body article.

"Reactivation of a Barr body is also possible, and has been seen in breast cancer patients.  One study showed that the frequency of Barr bodies in breast carcinoma were significantly lower than in healthy controls, indicating reactivation of these once inactivated X chromosomes. "

Week 5: Potential Articles

1.     Molecular Genetics https://en.wikipedia.org/wiki/Molecular_genetics 2.     Classical Genetics https://en.wikipedia.org/wiki/Classical_genetics 3.     Gene Pool https://en.wikipedia.org/wiki/Gene_pool
 * Could expand on gene therapy section, include efficacy of treatment
 * Address ethical concerns in molecular genetics
 * Potentially include diseases it has been successful in treatment of
 * Add to article including other uses of molecular biology, such as computational and systems biology
 * Currently no sources cited in this article - try to find reputable sources for info currently there or remove all uncited info
 * Expand upon Mendelian genetics mentioned in the beginning of the article, refer to pea plant experiment
 * Add to article discussion on phenotypes, expand on dominant and recessive alleles
 * Expand on gene linkage briefly mentioned in beginning of article - clarify that linkage groups are genes that are inherited together and that the transfer of the linkage group is called gene linkage
 * Missing some citations - find reputable sources for info currently there or remove uncited material
 * Include definition and explanation of gene pool in relation to evolution
 * Expand on section on gene pool centres, add citations
 * Include an example of gene pools and how they can change, such as in bacteria populations, those that are antibiotic resistant are more likely to survive and reproduce (gene pool changes to include only bacteria that are antibiotic resistant)

A lot has already been written for your selected topics. I encourage you to find either stubs or starter articles since you will graded based on the quality of the content that you will add. Good candidates are usually specific genes, proteins, molecules, etc that have little written about them so far. Please feel free to contact me if you have any questions. Otherwise, good job. Keep it up AdamCF87 (talk) 15:07, 17 October 2017 (UTC)

Week 7: Finalizing Topic and Finding Sources

CD8+ Cell https://en.wikipedia.org/wiki/CD8_cell Sources:
 * No citations - find reliable source for info currently there or remove entirely
 * Expand on CD8+ cell role and function
 * Add information on its role in diseases, such as HIV infection and type 1 diabetes
 * Include details on CD8 protein expressed on cell surface

https://www.immunology.org/public-information/bitesized-immunology/cells/cd8-t-cells

https://www.ncbi.nlm.nih.gov/pubmed/15053338

https://www.ncbi.nlm.nih.gov/pubmed/19111164

http://www.uniprot.org/uniprot/P01732

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.913.2257&rep=rep1&type=pdf

https://www.ncbi.nlm.nih.gov/pubmed/20636815

Week 8: Article Draft

I have some ideas to add to the article. A citation could be added to the info already there or could just be removed entirely. I am planning to add the specific role of CD8+ T cells in the immune system, using this article (https://www.immunology.org/public-information/bitesized-immunology/cells/cd8-t-cells) as my source. This article gives the overall gist and main functions of the CD8+ T cell, describing what kind of cells they destroy and how they destroy them. I also would like to include a section detailing the CD8 protein structure and how it relates to its function, based on both the previously mentioned article and this source (http://www.uniprot.org/uniprot/P01732). These sources provide evidence as to how the CD8 structural components work together to recognize and bind infected cells. Another section that could be included is the origin of CD8+ T cells (i.e. how they're made). This source (https://www.ncbi.nlm.nih.gov/pubmed/20636815) details information and evidence on the pathway a progenitor cells goes through to become the final CD8+ T cell product. Regulation of the CD8+ T cell gene by transcription factors could also be included, and can be evidenced by a study (http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.913.2257&rep=rep1&type=pdf) showing that a decrease in the Eomesodermin transcription factor results in a decrease in amount of perforin produced by CD8+ T cells. I would also like to add info on its role in diseases, such as HIV infection and Type 1 diabetes. A study on CD8+ T cell roll in HIV infection (https://www.ncbi.nlm.nih.gov/pubmed/15053338) showed that HIV viruses have adopted strategies to evade CD8+ T cell response. A study on CD8+ T cell role in Type 1 diabetes showed that CD8+ T cells also engaged in the destruction of insulin-producing pancreatic cells (https://www.ncbi.nlm.nih.gov/pubmed/19111164) in addition to CD4+ T cells. Please let me know what you all think and any input you might have. Is there any more information I should add? I'm concerned that I don't have enough to write about.

Week 10: Full Written Draft

CD8+ T cells (commonly known as cytotoxic T cells) are cells of the immune system. They contribute to the body’s adaptive immune response, and function to kill cells infected by intracellular bacteria, intracellular viruses and tumour cells. They express a CD8 protein receptor on their cell surface.

CD8 protein is composed of a CD8α and CD8β chain. Together, they function to recognize peptides presented by MHC Class I molecules (i.e. nucleated infected cells); This interaction allows the CD8+ cells to bind to infected cells.

CD8+ T cells are developed in the bone marrow and thymus; whereby hematopoietic stem cells will be made into lymphoid progenitor cells in bone marrow. These cells will then move to the thymus to be made into naïve CD8+ T cells. These CD8+ T cells will then move into the blood and circulate around the body. When the body is infected by a pathogen, CD8+ T cells will recognize, bind and kill infected cells by the secretion of perforin and granzymes, a pore-forming protein and protease, respectively. This is a similar process to how Natural Killer (NK) cells kill intracellular viruses and cancer cells.

Some studies have revealed that the transcription factor Eomesodermin plays a key role in CD8+ T cell function, acting as a regulatory gene in the adaptive immune response. Studies investigating the effect of loss-of-function Eomesodermin found that a decrease in expression of this transcription factor resulted in decreased amount of perforin produced by CD8+ T cells. CD8+ T cells have been found to play different roles in certain diseases, such as in HIV infection and in Type 1 diabetes. HIV over time has developed many strategies to evade the host cell immune system. For example, HIV has adopted very high mutation rates to allow them to escape recognition by CD8+ T cells. They are also able to down-regulate expression of surface MHC-I in cells that they infect, in order to further evade destruction by CD8+ T cells. If CD8+ T cells cannot find, recognize and bind to infected cells, the virus will not be destroyed and will continue to grow. Furthermore, it has been recently discovered that CD8+ T cells play a critical role in Type 1 diabetes. It was previously thought that this autoimmune disease was exclusively controlled by CD4+ cells – but recent studies in a diabetic mouse model showed that CD8+ T cells also engaged in the destruction of insulin-producing pancreatic cells. Week 12: Revised Written Draft

Introduction

CD8+ T cells (commonly known as cytotoxic T cells) are cells of the immune system that contribute to the body's adaptive immune response. These immune cells are characterized by a CD8 protein on their cell surface that allow them to recognize, bind and kill cells infected by intracellular bacteria, intracellular viruses and cancer cells. They are developed in the bone marrow and thymus, and are regulated by transcription factors and signalling components. CD8+ T cells have also been found to play various roles in different diseases.

Production

CD8+ T cells are developed in the bone marrow and thymus. The first step occurs in the bone marrow, where hematopoietic stem cells are made into lymphoid progenitor cells. These lymphoid progenitor cells will then move to the thymus, where they will be made into naïve CD8+ T cells. These naïve CD8+ T cells will then move into the blood and circulate around the body.

CD8

CD8+ T cells are characterized by a CD8 protein on their cell surface that functions to recognize and bind infected cells. The CD8 protein is composed of a CD8α and CD8β chain; Each CD8 protein has a molecular weight of around 34 kDa. Infected nucleated cells will present MHC Class I molecules on their cell surface. The CD8 chain on the naïve CD8+ T cell will recognize peptides presented by these MHC Class I molecules, and thus will allow the CD8+ T cell to bind to infected cells. Once bound, the naïve CD8+ T cell will become mature CD8+ T cell through regulatory mechanisms discussed in the next section. Function and Regulation

When the body is infected by a pathogen, naïve CD8+ T cells will recognize and bind infected cells through the recognition of MHC Class I peptides on infected cells by the CD8 protein on CD8+ T cells, as previously mentioned. Once bound, CD8+ T cells will kill infected cells by secreting perforin (a pore-forming protein) and granzymes (a protease) onto infected cells. The pores formed by perforin disrupts the protective barrier of the infected cell membrane, and will enable influx of ions and water into the cell, and efflux of essential nutrients, substances and proteins out of the cell - ultimately destroying the integrity of the cell. Furthermore, the granzymes will induce programmed cell death in the infected cell. Overall, this mechanism of destruction using perforin and granzymes is a similar process to how Natural Killer (NK) cells kill intracellular viruses and cancer cells.

The transcription factor Eomesodermin is suggested to play a key role in CD8+ T cell function, acting as a regulatory gene in the adaptive immune response. Studies investigating the effect of loss-of-function Eomesodermin found that a decrease in expression of this transcription factor resulted in decreased amount of perforin produced by CD8+ T cells.

Furthermore, maturation of naïve T cells to mature CD8+ T cells is mediated by both T helper cells and CD40 signalling. Once the naïve CD8+ T cell is bound to the infected cell, the infected cell is triggered to release CD40. This CD40 release, with the aid of helper T cells, will trigger differentiation of the naïve CD8+ T cells to mature CD8+ T cells.

Roles in Certain Diseases

CD8+ T cells have been found to play different roles in certain diseases, such as in HIV infection and in Type 1 diabetes. HIV over time has developed many strategies to evade the host cell immune system. For example. HIV has adopted very high mutation rates to allow them to escape recognition by CD8+ T cells. They are also able to down-regulate expression of surface MHC-I in cells that they infect, in order to further evade destruction by CD8+ T cells. If CD8+ T cells cannot find, recognize and bind to infected cells, the virus will not be destroyed and will continue to grow. Furthermore, it has been recently discovered that CD8+ T cells play a critical role in Type 1 diabetes. It was previously thought that this autoimmune disease was exclusively controlled by CD4+ cells - but recent studies in a diabetic mouse model showed that CD8+ T cells also engaged in the destruction of insulin-producing pancreatic cells.