Talk:Cystine/glutamate transporter

Untitled
"The dimer cystine gets taken up by glial cells and the monomer of cystine, cysteine, is taken up by neurons." This claim has been flagged as needing a citation, and I would like to *strongly* echo that sentiment. It is difficult to imagine that neurons are able to somehow change the substrate specificity of a transporter in this way. It is more likely that the author has become confused by the emphasis placed on glutamate influx via the Xc- antiporter in studies of neurons; this direction of transport (i.e., effluxing cysteine) can deplete a neuron of the cysteine utilized in glutathione production. This reader has never seen any evidence that neurons import cysteine. In fact, this is nearly impossible, as the oxidizing nature of the extracellular environment makes cysteine very, very rare there. — Preceding unsigned comment added by Neuroglider (talk • contribs) 17:48, 14 April 2021 (UTC)


 * Agreed, this is incorrect and has been deleted SDWingNut (talk) 20:34, 4 January 2024 (UTC)

Wiki Education Foundation-supported course assignment
This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): 7078kassels, Emmasarah95, SSCHMIDT1127, Egaietto13.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 18:55, 16 January 2022 (UTC)

Primary Review of SLC7A11 by Npsar20
Overall, job well done! Just a few minor improvements that I saw need to be done. First, in the “structure” paragraph the second sentence could be simplified a little, seeing that there is a run on sentence. There is also a grammatical error later in the paragraph. It reads "The human xCT is has an 89% similarity". The entire article could be cleaned up a bit in the sense there are (+) and (-) and this looks a little sloppy. If you could figure out how to change it to be a superscript then this would really change the look. The formatted layout is very well organized and I also thought key words were hyperlinked and this helped the article flow well.

There is only one reference listed, which I find shocking for the amount of information they have implemented. Since there is only one reference listed, this is one I reviewed. This one reference, however, was used correctly, and the information in the article matches the information presented in the reference. This means that no original research is used in this article. It also correctly does not include any original research or copyright / plagiarism infringements.

The editors did a good job of staying on track and keeping focused on the main goal of improving this stub. I thought key words were hyperlinked when necessary and I thought they did a great job in the description of how the SLC7A11 works in the different diseases, without turning the focus to the specific disease. SCL7A11 was the main focus throughout.

The editors remained unbiased and focused on the main point throughout the entire article. Also I think adding an image or two could really heighten the level of this article. It would allow the (not so scientific) reader to actually envision what a glutamate transporter looks like and visually how it works. Npsar20 (talk) 00:38, 20 April 2016 (UTC)Npsar20

Response to the Primary Review of SLC7A11 by Npsar20
Thank you for your feedback. We have taken your suggestions into consideration such that we have reformatted the introduction paragraph by taking out the heading and changing it to “SLC7411”. Grammatical errors have been fixed but we will continue looking for more. We are currently trying to figure out how to make the + and – signs into superscripts. There were more references listed as citations were made. More images will be added such as an image of the protein and an image of the cysteine/glutamate transporter. Thank you again for your suggestions and review!

Egaietto13 (talk) 17:36, 23 April 2016 (UTC)

Daniel Peters' Secondary Review (BIOL 3501 Marquette)
First off: you've collected all the information that is appropriate for a Wiki article. There's a lot there, and good job on getting that all together. Overall: -Needs some pictures! A quick Google image search shows at least some pics. I know this isn't the easiest subject to find a pic on, but at least find something relevant to relieve the reader from the text. -I'm pretty confused on the part where Xc comes into all of this. Xc could use a better introduction for how it relates to SLC7A11, especially considering how frequently Xc is referenced within the article. -Move the introduction text up in the formatting so that it can be seen immediately when you see the page (when you click on the link to the article)...reader shouldn't have to scroll down to read the introduction. -REFERENCES! The in text references don't lead anywhere. Make sure to use the citation function to actually link your citations so that the reader knows what your reference is. Don't just leave that info in the "further reading" section, put it in the references.

Introduction: -First sentence seems to state that the gene is the actual transporter. Recommend changing it to say something more like "SLC7A11 gene codes for this transporter". As it is, someone with less background in biology may think that the gene is the transporter itself (a long shot, I know, but still)

Structure section: -"which is when one substance"...the 2nd sentence is really long and confusing. Should break it up into smaller bits. "the antiporter has uses"...eliminate "has" or "uses" for grammar (quick fix, I just don't know which word you'd rather use) -Generally, could use more citations. There's a ton of info here that, if no one trusted you, it may seem like you're just making it up. "this release also has a physiological role" sentence needs some fixing

Clinical Applications section: Drug Addiction heading: a ton of info here (good), just kind of hard to follow on the first read through. That's probably just a problem common with all reading, and I may just not be a great reader, but anything you can do to make this section easier to follow would be great. Gliomas heading: change the word "basically" in the first sentence to "essentially", see if it sounds better Alzheimer's heading: cool finding, cool stuff. Maybe this could be a section you find an image for?? Danielggpeters (talk) 02:16, 18 April 2016 (UTC)Dan Peters, BIOL 3501 Marquette University

Secondary Review from SEReichert
I think you guys made a good contribution to this article. However, I think that you could benefit from making a few changes in order to raise the quality of your article.

First, I think that it would be more aesthetically pleasing (and more like other Wikipedia articles) if you dissolved the 'Introduction' heading and added that opening paragraph under the main 'SLC7A11' heading, putting the general overview of the gene before the contents section.

Second, I know that it may be difficult to add any photos or images of this gene, but I think it would strongly benefit your article to add a few illustrations. This would help explain some of the material that is hard to visualize for the typical reader. For example, I think a diagram of where the SLC7A11 gene is expressed in the brain and a diagram of the structure of the gene would make good contributions to your article.

Third, I think you guys should look into how to make raise the + sign for Na(+) or how to raise the - sign for Xc(-). I do not know how to do this, but I have seen it done correctly on other pages. I still know what you mean by Na(+) and Xc(-) but its more visually appealing to have it written the traditional way.

Finally, I am confused as to what the numbers (1) and (2) mean in the 'Structure' heading. Are you referencing a source here or making a different point? I think you should clarify what you mean with these numbers.

I think that there are a lot of good aspects to your article and by adding some images and fixing some formatting of words using wiki markup, I think it could be a great article.

SEReichert (talk) 21:44, 18 April 2016 (UTC)

Primary Review of SLC7A11 by Mbozsik
The article written about SCL7A11 was informative. The authors did a good job of bringing in many relevant topics to the discussion of this protein. I liked how they thoroughly addressed the role of this protein in disease states. In that same breath, by covering a variety of diseases that involve this protein, I wonder why the authors decided to focus on these ones specifically. What about these diseases makes them the ones selected to be written about on the article and not other ones. Covering a broad spectrum of diseases allows the reader to put this protein into context rather than simply reading an article that has less obvious relevance to medicine. My one critique is that the paragraphs under the heading “Regulation”, “Glutamate” and “Cystine” are not written in a way that is easy to understand. The language used is not specific, and therefore does not sound scientific, because scientific writing must always be specific. Other than that, the paragraphs that relate SLC7A11 to various diseases was interesting and overall well written.

The authors did a good job of covering many points, diseases especially, that this protein is involved in. A greater emphasis could be placed on the normal functioning of the protein, that is the role of the protein when it is not involved in pathologies. When the average researcher is looking up this protein and attempting to find information on it, it can be assumed that this individual is not purely looking for the pathological implications of this protein. It is unclear whether the goal of the article was to give the pathological relevance of this protein, but it seems that that is the bulk of the contributions these authors made to this stub.

The authors definitely need to include more pictures in the article. The lack of pictures makes imagining the protein in vivo more difficult. I would include a picture of the protein and an image of the cysteine dimer and cysteine monomer. As well as several images relating to the pathologies. The authors did a good job of keeping the tone of the article neutral and not interjecting their opinions into the article. The article remains neutral and not catered to a specific audience. There is a prevalence of technical language throughout the article, but I assume this is going to be hard to avoid given the specific and technical nature of the subject matter.

In the article, there are references indicated throughout the article, but are not listed below in the “References” section. I am not sure if I am simply not seeing them or what, but I the lack of sources listed in the references sections is alarming, considering the article is referring to sources that appear to not exist. The one source that was listed was indeed sighted correctly and did say what the authors referenced that it said. It is also verified that the authors did not use original research in their article.

Mbozsik (talk) 04:13, 21 April 2016 (UTC)

Response
Thank you Mbozsik for your review; we have taken your concerns into consideration in making our edits to ensure that our article is cited correctly and informative. We are adding pictures and editing the references. The reason why we discussed certain diseases was due to the fact that those specified diseases are the only ones that showed a correlation in our gene. In all of our references they only discussed the stated diseases so in turn we only had information on those diseases. We have fixed/are fixing the citations so that they are in correct and proper to the wiki guidelines. We have also read through and made changes in order to ensure our article is an easy and informative read. SSCHMIDT1127 (talk) 17:49, 23 April 2016 (UTC)

Secondary Review
While there has been a good deal of quality information contributed to this article, I believe work can be done to clarify the subject for the ease of the reader. Firstly, the introduction section need not have an individual header, but rather just exist at the top of the page. Also in this section, the addition of an image could be helpful, though I could see how one may not be easily accessible for the topic. Clarification should also be given to the naming and referencing you make to the gene through the article. In the introduction you mention and continue to use Xc(-). A more direct statement of this being the gene in the first opening sentences would be appreciated if this is how you are referring to it. The same would apply to Xct that is mentioned in the structure and regulation sections. Lastly, though I'm sure you are aware of this by now, your citations are not in the Wikipedia mark-up language and need to be converted. It also appears that the actual citations may have been inserted into the reference section, from which they will then end up in the proper citation location through the mark-up language and will then need to be removed from the reference section. Keep working and I'm sure this will turn out to be a great article! Edavis95 (talk) 00:39, 20 April 2016 (UTC)

Primary review for SLC7A11 by SinghM154
Overall, the article has information for the readers, and it is clear that the group members did research on their subject of SLC7A11, however the article itself could benefit from a few changes. One thing that clearly stands out, as soon as opening this article, is that there are absolutely no visuals to compliment the extensive text. Especially when talking about a topic as complex as this, it would help the readers a lot more by having aids that further elaborate on the texts. Seeing how this is not as common of a topic that many people know about, it may be hard to find exactly the right picture to go with your very own text, but there would definitely be something on the internet. (the first image on http://www.pnas.org/content/112/33/E4600/F14.expansion.html seems to have a nice diagram of the pathway)

As for the introduction, a few changes could be specifically made here as well. With most Wikipedia articles, the introduction is usually the first thing that readers read. This being said, this section should actually come before the table of contents. Along with placement, the introduction should give enough information to the point where is someone just wanted some casual information on the subject, that they could receive if from just this section, as this is the section that pops up on Google, and is generally as far as some people read. This being said, the current introduction does not seem to do that, and this is partly due to the use of pretty complex terms that aren’t as elaborated. The main term needing this elaboration would be the Xc-. Having this in the in the intro with minimum information is rather confusing. I suggest using visual aids, and maybe linking to another page with more information on Xc-.

However, there were many aspects of the article that I found great. The Clinical Applications section was great and informative, showing the importance of the gene. This section feels well researched, and someone who does not much about the medical and mechanics of this gene still has a chance to see how exactly it is incorporated in health.

The structure section was slightly confusing, due to one reason in particular, and the was with the (1) and (2)s. I was not quite sure what that had meant.As for the last thing, the reference section only had one reference, while many references were used throughout the article. I’m just assuming that may be due to work-in-progress, but I would get on that sooner than later — Preceding unsigned comment added by SinghM154 (talk • contribs) 02:16, 20 April 2016 (UTC)

Response to Primary review for SLC7A11 by SinghM154
Thank you for your feedback. We have taken your suggestions into consideration such that we have reformatted the introduction paragraph by taking out the heading and changing it to “SLC7411”. More images will be added such as an image of the protein and an image of the cysteine/glutamate transporter. We also have made sure that the introduction paragraph comes before the Table of Contents. The term Xc- has been expanded on and possibly will be adding an illustration to help explain it better. The structure paragraph had (1) and (2) in order for the editors to be able to connect their sources but they had not been correctly formatted. The citations are now made and correctly formatted. Thank you again for your suggestions and review!

Egaietto13 (talk) 17:37, 23 April 2016 (UTC)

Primary Review by CLucy1994
Overall, I thought your article was well written and informative. I have a few major concerns, however. Throughout your article, you mentioned Xc(-), but never really give a clear description of what it is. From the title of the article, I would think the primary topic would be the SLC7A11 gene, but your focus throughout the article seems to be on Xc(-). I am assuming this is the protein product and antiporter that you mention throughout the article, but I would add clarification to the introduction or another location if you are going to keep referencing Xc(-). Also, a lot of your sources were not linked correctly or were absent. Many times there was just a number in parenthesis "(1)" instead of a proper link. I also took a look at the 1 article that is currently listed under your references. I found a quote that said "Sato and co-workers identified the promiscuous 4F2 heavy chain (4F2hc/CD98/SLC3A2) as one subunit and a new 502 amino acid protein named xCT or SLC7A11 as the specific light chain subunit of system Xc(-)" This may be useful in clarifying that the gene in question encodes for a specific portion of the antiporter. For the majority of your article you are talking about the antiporter itself (Xc(-)), not what the gene codes for, the light chain xCT.

Also, in the article, Xc(-) is written as a x subscript c superscript -, I would change your wiki article to match.

I made some slight edits to some grammar and excess repetitiveness on the edit page. Feel free to change or remove my edits.

Introduction
In the first sentence you say "gene is a sodium-independent glutamate transporter that is chloride dependent" Is the gene is a transporter? Or do you mean it encodes for a protein that functions as a transporter?"

Structure
I would make the "+" after Na a superscript. Also, I would change the "which is when one substance" and make 2 sentences. My suggestion: "with a one to one counter transport. This occurs when one..." Some of your sources are also missing their links. When you say "The structure of this gene includes a specific light chain," do you mean "the structure of this protein?" The gene itself encodes for the light chain of the transporter and other genes are responsible for the other portions of the protein complex. I would also add a link to "cDNA."

Regulation
After reading this section, I am unsure exactly what you mean by regulation. Your wiki article is on the gene, but you seem to be focusing on the gene product, the protein. I would suggest rewording the opening sentence from talking about regulating expression to one that refers to the protein being a mechanism for regulating the levels of glutamate/cysteine. As it stands now, the term “regulating expression” would suggest to me that you are talking about mechanisms that alter the transcription and translation of the gene, which from what I gather isn’t what you are talking about. When you say "There are many mechanisms that exist to regulate expression because it is not the sole determinate of extracellular glutamate or intracellular glutathione," it doesn’t really make sense. You mention there are other ways of regulation of glutamate/glutathione. This would suggest that the regulation of the gene in question isn’t fundamental to glutamate levels. Maybe say something like “There are many mechanisms that exist to regulate gene expression, though other mechanisms exist that also determine extracellular glutamate and intracellular glutathione levels.” You said "A key regulator is extracellular glutamate, when it becomes excessive it goes from excitatory transmitter to an excitotoxin." I would reword this somehow, because it’s poorly worded. This is just a suggestion.

Glutamate
Do you have any sources to back up this information? It is important for future edits to know where all of your information comes from.

Cystine
You wrote "Cystine is the oxidized from two cysteine molecules by the formation of a disulfide bond. This amino acid is used in the SLC7A11 cystine/glutamate transporter and is usually imported into the cell. Cysteine is also a rate-limiting substrate." Maybe try combining these two sentences to get rid of such a short second sentence. For example,"This amino acid is a rate-limiting substrate used in the SLC7A11 cystine/glutamate transporter and is usually imported into the cell.”

Drug addiction
You wrote "leading to a decrease inbasal, extra synaptic glutamate." Do you mean to say “in the basal ganglia?” I wouldn’t shorten it to “basal.”  Later you wrote "This increase in system Xc(-) activity leads to an increase in extrasynaptic glutamate, leading to stimulation of Group 2 mGluRs and an inhibition of synaptic release of glutamate." I would suggest changing the second “leading to” to “causing,” or something else to decrease the repetitiveness.

Schizophrenia
You only site a source at the very beginning of this section. I would add more links to the source throughout in order to indicate to future editors where the information was from. Also, you said "It has been proposed that schizophrenia may be due to abnormal excitatory signaling in the prefrontal cortex region of the brain.3 An increase or a decrease in glutamate signaling may occur." I would combine these two sentences to make things less choppy. My suggestion: "It has been proposed that schizophrenia may be due to an increase or a decrease in glutamate signaling, leading to abnormal excitatory signaling in the prefrontal cortex region of the brain.” Later you said "An increase in the expression of Group 2 mGluRs has been associated with schizophrenia. This could arise from a chronic understimulation of these receptors, causing more to be expressed." Again, I would combine these two sentences because they seem to go well together. My suggestion: “An increase in the expression of Group 2 mGluRs, which could arise from a chronic understimulation of these receptors, has been associated with schizophrenia.”

Neurodegenerative Disorders
Good information, but you never specifically mentioned how or why the cell death is a central part of neurodegenerative disorders. Also, are there any specific disorders that it effects?

Gliomas
I would not say “basically,” as well as combine the first and second sentences. My suggestion: “A glioma a glial-derived tumor that can be induced by an increase in glutamate levels due to an increase in system Xc(-) activity.”

Amyotrophic Lateral Sclerosis
Very good section

CLucy1994 (talk) 14:36, 20 April 2016 (UTC)

Response
Thank you CLucy for your in depth review of our article. We have taken your suggestion into consideration in making the final edits to the page. We appreciate the edits you have personally made and the references/suggestions you listed. We will be editing our references in order to ensure that the proper material/information is cited correctly for future readers. We are also scanning over sections and making any grammatical changes along with phrasing sentences properly to ensure an easy read. Thanks again for your feedback. SSCHMIDT1127 (talk) 18:01, 23 April 2016 (UTC)

==Secondary Review by 0272thinkap=

Overall, I think this article is written very well. The representation of the material is good and while the article is also broad in reach. The citations and sources seem to be used appropriately and the links are very helpful throughout the article. The headings and sections are appropriate and organized well as they help the reader to easily navigate through the article. If I could change anything, I would add some illustrations to article to help in the readers comprehension and focus. 0272thinkap (talk) 14:52, 20 April 2016 (UTC)0272thinkap

Secondary Review by G.T.L.Neuro
Overall I think that the article is great in its content and it also seems very informative, however there are some things that could be fixed to make it better. At some points the article can get too technical and in some of the paragraphs there seems to be a lot of links making the text a large percentage blue. Potentially you could add in more explanations rather than linking to everything. Also, is it necessary to say sodium independent and also chloride dependent when describing the ion channel? if this is necessary then could you add in some sort of explanation, because this was somewhat confusing to me. G.T.L.Neuro (talk) 03:15, 21 April 2016 (UTC)