Talk:2013 Group 2 Project

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Revision as of 13:02, 23 May 2013 by Z3377769 (talk | contribs)

2013 Projects: Group 1 | Group 2 | Group 3 | Group 4 | Group 5 | Group 6 | Group 7

  1. Do not remove this notice {{2013 Project discussion}} from the top of the discussion page.
  2. Newest student comments should be entered at the top of this current page under the subheading "Student Discussion Area" (you cannot edit the sub-heading title).
  3. All comments should begin with your own signature button, that will automatically enter student number date/time stamp.
  4. Do not use your full name here in discussion, if absolutely necessary you may use first names only.
  5. Do not remove or edit other student comments.
  6. Use sub-headings if you want to add other draft information, images, references, etc.
  7. Only your own group members should edit this page, unless directed otherwise by the course co-ordinator.

Group Assessment Criteria

  1. The key points relating to the topic that your group allocated are clearly described.
  2. The choice of content, headings and sub-headings, diagrams, tables, graphs show a good understanding of the topic area.
  3. Content is correctly cited and referenced.
  4. The wiki has an element of teaching at a peer level using the student's own innovative diagrams, tables or figures and/or using interesting examples or explanations.
  5. Evidence of significant research relating to basic and applied sciences that goes beyond the formal teaching activities.
  6. Relates the topic and content of the Wiki entry to learning aims of cell biology.
  7. Clearly reflects on editing/feedback from group peers and articulates how the Wiki could be improved (or not) based on peer comments/feedback. Demonstrates an ability to review own work when criticised in an open edited wiki format. Reflects on what was learned from the process of editing a peer's wiki.
  8. Evaluates own performance and that of group peers to give a rounded summary of this wiki process in terms of group effort and achievement.
  9. The content of the wiki should demonstrate to the reader that your group has researched adequately on this topic and covered the key areas necessary to inform your peers in their learning.
  10. Develops and edits the wiki entries in accordance with the above guidelines.

Week 2 Project topic selection, preliminary researching on the topic.

Week 3 By the next practical class (after the mid-session break) there should be sub-headings and content on your actual project page and interactions between individual group members on this discussion page.

Week 4 Each group member should now have selected 4 papers relevant to their section of the project. These, or any other papers, can now be used to generate content (text, images and tables) within the project page. Students can also work on additional sub-headings on the project page.

Week 8 Peer assessment of group project work.

  • Each student will carry out an assessment of all Group projects other than their own.
  • This written assessment should then be pasted on the actual project discussion page and your own individual student page.
  • The peer assessment for each project should be concise and include both positive and negative critical analysis of the current project status.
  • The actual assessment criteria (shown above) can be used if you like.
  • Each student assessment should be your own work and be completed before the next Lab.

z3377769 Peer Mark

Group 2 peer review 1. Content and writing - Intro: is fine, as a definition but not as an intro. My old school teachers always said about intros, tell me what you are going to tell me. This defines cytokinesis which is a good place to start, but I think you need to mention what you will be discussing in the rest of the page. - History: I have never studied this but no discoveries between 1902 and 1961? The table and colours is good. You also have a good amount of information about the discoveries. - Mechanisms o Assembly  Looks all good to me I like the way your picture includes a lot of the features you mention this section o Cleavage Plane Specification  Maybe in the introduction you could say “separated chromosomes is important for preventing chromosome loss”. Seems a bit less wordy  This is really nit-picky but in the RhoA paragraph about halfway down I think u can lose “the site where, ultimately …”. You have mentioned that previously I don’t think u need to again. o Contractile ring  My eyes could really do with a picture at this point. Double spacing would also help to break the sections up. And that first sentence is a bit long.  All your descriptions of these proteins are good, I think this is the level of technicality that mark is looking for. o The rest  This is really good information, but it’s a huge bloc of information, double spacing and picture, even simple drawings if it’s possible would help a lot - Microfilament organisation o Second sentence you have “formed at en equal distance”. Nothing major o Really like the numbering system here. Well done, nice and simple - Plant vs. animal o Maybe a table? Compare and contrast or a flow chart. It’s great you have all this information but at this point I feel pretty saturated trying to read it all. - Failure o PICTURES!!!! Good stuff o Said it before and say it again, good use of technical language balanced with relatively simple explanation. Really well done - Current/future o Please double space o Good to have the external links in there under the headings, this project has so much information! 2. Referencing - Bibliography looks good, nothing is entered twice, I think you have a good number of sources that you have accessed. - Pictures have all the right referencing, copyright and disclaimers needed 3. Elements of teaching - Lots of work has been done here and it shows, lots of info on the page and external links as well as videos. One could obtain a pretty solid overview of cytokinesis from this page. 4. Presentation - That middle section needs to be broken up. Double spacing, some tables maybe for plants vs. animals pictures, drawings. Maybe even subheadings for the individual proteins and mechanisms. Make it neat, tidy and not just dense text.

Criteria: 1. The key points relating to the topic that your group allocated are clearly described. 2. The choice of content, headings and sub-headings, diagrams, tables, graphs show a good understanding of the topic area. 3. Content is correctly cited and referenced. 4. The wiki has an element of teaching at a peer level using the student's own innovative diagrams, tables or figures and/or using interesting examples or explanations. 5. Evidence of significant research relating to basic and applied sciences that goes beyond the formal teaching activities. 6. Relates the topic and content of the Wiki entry to learning aims of cell biology.

Very interesting choice of topic! Areas of interest I'd hoped to be covered were done quite nicely, as well as concisely - I appreciate how the process is laid out and even plants are mentioned!(1) Good subtopic coverage with nice subheading breakdowns and images, although there is a lot of extra room just waiting for a image to break up all the text - perhaps the inclusion of more images may even allow you to actually cut out some text as it seems a bit overwhelming, especially to the eyes of a person unfamiliar with our topic seeking to understand more. Although easy to follow, you may agree that there are A LOT of subheadings, maybe less is more with these?. Nice table, however maybe there are too many colours? Also your introduction is very short and sweet, I like how it is to the point so visitors know exactly what you will be talking about. The image arrangement is also different, this is nice as it breaks up all the text and isn't so boring as if they were all on the same side. I suggest only the first word in the subheadings be capitalized, and other be only if necessary - this just seems more correct, why Capitalise Something Which Need Not Be?(2) Content seems correctly referenced/cited, however may I suggest the references are moved from the end of the sentence to the inside? Just seems more cohesive, plus they seem a bit random just hanging off the end with not much of a guide as to what they actually refer to(3) The videos are a nice touch, as is the glossary, I feel it is both helpful to newcomers and fellow students looking for information(4) It is clear that significant research has been done, this is evident by the page's CONTENT, but then why are there only 40 references? Perhaps you guys found some excellent papers which were very helpful, if this was the case then well done! Abundant research must have also been put into finding the videos and images, however as I said, more images would be great(5) Cytokinesis is extremely important to proper cell division, and so I think your topic is well-chosen and relevant, I also find it interesting as we are not taught much about it in classes; so I think many like me will look forward to reading it(6)

z3374507 assessment - Group 2

The key points are very thoroughly addressed and the choice of headings and sub headings is excellent. The categorisation of the content into its relevant headings demonstrates that the group has done a significant amount of research. The glossary is a particularly useful section for viewers who are not familiar with the topic area. The formatting from ‘Cytokinesis Failure’ onwards is really good. The referencing of the text and images is well done.

There is a significantly large portion of the page which lacks images. This makes the test/image images and balance of the entire page uneven. Also adding a brief statement of what is happening in the diagram in relation to cytokinesis instead of just a description may make the images make more of an impact.

Peer Assessment

Group 2 – Cytokinesis

The introductory paragraph significantly lacks information. Perhaps a little bit more description briefly summarising the other sections of the wiki page in the introduction would make it more substantial. The image in this section is nice and appropriate, with correct referencing. The history section is lacking content. You need to add more years and descriptions of the discoveries in those years. It’s good that you have added correct references for each of the 3 discoveries you’ve mentioned so far. Perhaps adding some images to support some of the discoveries would make this section look more interesting. The colourful table format is a good idea.

The mechanisms section is the best so far in this wiki page. There is a good amount of content with appropriate referencing. There is only 1 image in this section and it has appropriate referencing. It would be nice to add maybe two more images to support the text, as there is a lot of text. I also like the clickable links to the words in the glossary.

The microfilament organisation sections seems a little brief, perhaps you should add a bit more information and also use an image to support the text to make it more interesting.

The plant vs animal cells section seems good and clear and to the point. However, there are no references, you need to add references. It would also be good to add some images to support the text as it’s difficult to read so much text with no supporting images.

Cytokinesis failure section is reasonably good so far, with appropriate referencing for the text and images. It has a good balance of text and images.

The “current/future research” section heading should be edited to get rid of the slash and just put “Current and Future Research”. So far the content is relevant with good descriptions of the research findings. You need to add the proper reference for the papers though, not just external links to the papers.

The external links has links to good images and videos that are relevant and appropriate to the topic. Add a template for the external links disclaimer to say that some of the links may not work in future if those websites take down that content.

The glossary list has appropriate choice of words and is good so far.

Group 2 Feedback

Introduction describes clearly what cytokinesis is about. The picture is very eye catching! Which makes the reader to continue and read what it is all about. History table is referenced correctly and contains list of events but need to mention few more key events. The Assembly of the central Spindle section is very detail and gives enough information. Linking the terms was a great idea. It is suggested to include more diagrams, since there are presents of detail information for each process and subheadings. Current/future research was presented clearly with the relevant journal articles. Image section should not be left empty. And the glossary seems really helpful for understanding some of the complex terms.

Group 2: Cytokinesis:

Peer Marking

Introduction concisely describes what cytokinesis briefly is about. It does not use complex terms that will confuse the reader and even provides a nice picture. The history does list important events and is referenced correctly but clearly is lacking a few more recent key events (ends in 1972). Not quite sure what “ZEN-4 is required for cytokinesis9778533” is for, but that should be noted in the discussion page and not left there. The Assembly of the Central Spindle section does provide helpful information on the topic and linking important terms to the Glossary was a brilliant and helpful formatting decision. The diagram provided also aids in the understanding as there are several complex terms used in this section. The following sections in the Mechanism subheading provide appropriate information but it was incredibly difficult to read due to the huge wall of text each subsection had. Adding some pictures and diagrams would do a much better job at engaging the reading and probably explaining the topic. The microfilament organisation and animal/plant cell cytokinesis section would be better with a diagram as well, since it is a step-by-step process. Including cytokinesis failure made the wiki page well-rounded as it is important to discuss the malfunctions and problems that can arise. Diagrams were helpful and explanation was not too complicated despite the complex terms. Current/future research section was good as it easily summarised the various journals found and what it all meant in reference to the topic, but the referencing might need to be changed. External links and glossary were incredibly helpful. Images section should not be left empty. Discussion page is filled with images but some discussion about what to include. Overall, with the inclusion of more images, the wiki page should be complete soon.

Group 2 peer review

Introduction :The information was good however I think an introduction should be a slice of what you will be covering in the wiki page. I don’t think this intro offered any insight of what to expect. The image used it eye catching and great to use for an introduction. There are no citations in the introduction.

History : I enjoy the colour scheme of the table. However I believe three entries is not enough to successfully give the reader a taste of the evolution of knowledge on this subject area. I’m sure a lot has happened after 1902.

Mechanisms : The headings, subheadings and general layout was easy to follow. I liked how the bold words take the reader to the glossary however it goes not take you to the specific word so it seems slightly pointless. But then again, it does save the reader from having to scroll to the bottom. The level of information was excellent and shows that the group has done extensive research. However, there are so many proteins involved, it makes me not want to read it. Perhaps the information should be simplified? More images are required to break up this dense body of text. This is make it more enjoyable to read.

Microfilament organization: There are no references here! I think it is essential to add an image of the microfilament organisation here. The information itself is concise and reads well.

Animal vs plant cells: Since this section is about comparison, I think it would be FAR more effective to use a table.

Cytokinesis failure: This was a well written and well structured section. The use of images helped to break up the text. That first image has no copyright information added.

Current research: I like the external links because they allow the reader to pursue more information if they want to.

Further comments: All of the images were relevant to the information discussed which is helpful to the reader. External links to videos are a great idea because it enhances the learning experience for students. Many students would rather watch a video than read if they want a quick brush up or overall impression of the topic. There was discussion on their page which included possible changes and new topics to be included after learning new material from the cell division lecture. They have acted upon these changes.

Group 2-Cytokinesis


  • Introduction is very brief but excellent. Maybe you can add some references.
  • Image is uploaded properly with the appropriate information.


  • The timeline is brief and maybe more poitns are needed but the ones listed are relevant and referenced well.
  • There are too many colours however, maybe stick with a pattern like the other tables used in projects.


  • Good use of the sub headings to break up the information. The information itself is excellent and well readable and it helps that you have linked the terms to the glosaary.
  • The image uplaoded is referenced correct and appropriate information is added. However possibly add more pictures to break up the rest of the section as it is mostly text.
  • The content of this part is easy to follow and is informative.

Microfilament organisation

  • The information is once again relevant and succinct
  • Need to add some references.
  • Maybe add pictures however i dont feel its too important as the section doesnt have too much content.

Animal Vs Plant Cells

  • Execellent structure and infromation is once again detailed and succinct.
  • There are no references however and adding references would strengthen the section.
  • Add an image if it is possible

Cytokinesis Failure

  • This section is almost perfect.
  • Good break up of section with the two sub headings.
  • Many images used and they are uploaded correctly as well.

Current and Future Research

  • Well researched information
  • What about future research?
  • Could an image be used?
  • The link to the pages is good.

Overall This project is researched very well and there is little to change and add. It reads well and informs well. Futhermore the use of external links is excellent as some other projects lack this part.

  • Cytokinesis: I like the information that has been provided for cytokinesis but unfortunately it does not tell the reader the actual purpose of the wiki page is or how cytokinesis will be explored in the context of cell division. The image is relevant and I like the fact you have included a good, detailed description of what the image is signifying. Though no reference is used in the introduction which I believe needs to provided for copyright reasons.
  • History: The table of history is incomplete. There are only two entries; more information should be included and it is important to provide up-to-date information as well. The history section could be improved by adding more entries after 1972. Though the colour scheme for the table is good as the information can be easily seen.
  • Mechanisms: It’s good that they have you have included a cartoon depicting the steps in cytokinesis with relevant information. Though It would be good if you could provide an EM or another image relating to this section. Also there is a lot of information in this section and this may not be very user friendly as they would have to read a lot of texts. I suggest simplifying the information a little and adding a student drawn image depicting the various structures described. Also, I think more references are needed for this section as the long paragraph included only one reference.
  • Microfilament organization: The information is concise but you need to include references as there are no references used! Furthermore, I strongly suggest to you to find an image relevant to microfilament assembly and include that in this section. Not only does it add value to the layout but it also makes it more user friendly.
  • Animal Vs Plant Cells: Since this part of the project page aims to explore the differences of cytokinesis in both animals and plants, I strongly recommend you to use a table with a good colour scheme to represent this information. There are lots of information in the other sections of this page, so to make it more reader friendly, you should consider a table instead to describe the differences of cytokinesis in animals and plants.
  • Cytokinesis Failure: The use of images is great but more elaboration on what the images are presenting would be great. You have provided a description of an experiment conducted by the researchers, which is a good idea but I think the information needs to be revised and simplified. It can really confuse the reader if they are not familiar with the scientific jargon that’s there. Nonetheless, as a whole, this section demonstrates good research but again the expression of ideas in a concise manner is somewhat lacking.
  • Current Research: A few external links have been provided which I think is a very good way of directing the reader to further information on current research in this area. Though I suggest that you include some form of graphs or other relevant data to support the research outlined in this section.
  • Glossary:The glossary provides definitions for a number of words which I think is a very good thing to see as you are helping the reader to better understand this page but you need to complete it.

Group 2 Introduction

  • Introduction is informative and succinct. However the first sentence (definition of cytokinesis) could be more detailed. The definition given is a bit broad and could apply to mitosis as a whole. What stage of mitosis does it occur? What occurs in this process that separates it from other processes?


  • Overall, information here is good, well referenced and relevant.
  • Im confused by the colours – Why are the first 2 dates a different colour to the last one? Should it be alternating instead?


  • Overall, a good section. Processes and complexes are explained and defined well. As far as I can see, citation is good.
  • The links to the glossary work very well.
  • A few more pictures both left and right would make this section pop.

Microfilament organisation

  • Good structure. Detailed and succinct
  • Citation needed
  • Having a definition for ‘microfilament’ would be good.
  • A picture could be good but not necessary

Animal vs plant cell

  • Having thi section as a good idea. There are lots of differences between plant and animal cells and this section describes it well.
  • Point form makes this easy to take in
  • In DIRE need of citation

Cytokinesis failure

  • Once again, this is another good section. Its good to know what happens when things go wrong and this section does it well. Well written.

Current/future research

  • I like how there are link with every heading.
  • A lot of good and relevant information. Structured and written well.

Overall this is a very good page. My biggest concern is that there are only 40 references for such a lengthy page. A lot of information has very little (and sometimes no) citations. This would be my number one priority as copyright/plagiarism is taken seriously.

Peer Assessment Group 2 Introduction is nice an bold, jumps right in and explains cytokinesis, might want to explain what is going on in your page to give us a heads up to what is to come. History table has strange colours and minimal content but that might be because of the studies done at times? Really well thought out mechanisms. I especially like the link to the glossary. Broken down into easy to read segments. To make it flow better you could put CPC before the others so that it is inline with the statement that introduces them. You've explained it really well and using the plant vs animal model was very clever. A really well done page with well thought out ideas and an amazing structure. Research at the end was very well thought out by including summaries. Pictures are relevant and I can see heaps of effort has gone into this page. Might need a picture in the mechanisms section, quite text heavy but a fantastic page otherwise.

Peer assessment


  • Comprehensive and well summarised explanation of what cytokinesis is, may need to add references used
  • May want to briefly summarise what will be discussed on the page
  • Good accompanying image which has be properly formatted and referenced


  • This section could use a bit more work, so far the summaries of the key discoveries which have been mentioned are relevant and to the point
  • May want to stick with one colour for the table


  • Good breakdown of this section, good use of subheadings
  • Evidence of significant and in depth research
  • Might want to refer to specific studies/research papers to enhance section a little further
  • Linking to the glossary is very useful
  • Could use more images to break-up the text and to help with the visualisation of what is being explained in this section
  • Good use of a range of references
  • Image is well formatted and referenced; all the necessary requirements for an image on the page are covered. May want to explain the image in own words

Microfilament Organisation:

  • Concise and easy to understand
  • This section would be further enhanced with a diagram and/or image of the contractile ring and cleavage furrow

Animal vs Plant Cells:

  • There’s a comprehensive explanation of the differences in the mechanisms of cytokinesis in plants and animals
  • This section needs referencing
  • Another way you could structure this section is in a table

Cytokinesis failure:

  • Good use of subheadings to break-up the section
  • May want to explain the difference between stage I and II failure
  • Good balance of image and text in this section
  • Information is well researched and summarised
  • Images look to be properly referenced and all required info is there

Current/Future Research:

  • Good summary of a range of current studies
  • Could use more info on the direction of future studies
  • Good use of links
  • May want to add to the reference list
  • It would be good if you could include an image from the studies

Overall, the topic appears to have been well researched, a few of the sections need some finishing off and a range of sources have been used but could use more references. Good use of links, external link section is very useful and adds to the page. Glossary is on its way to being completed and can see that it will include abbreviations and technical terms, like the way the text is linked to the glossary. The page could use a few more images to balance out the text.

The format of how the facts are presented is good (ie. bullet points, linking words to glossary, videos). Explanation on the diagrams did help in further understanding the topic. The facts are concise and easy to understand. Lack of diagram. The table colour division could be improved.

Intro: Maybe need to define cytokinesis better, you have that it’s “the process that leads to the production of two daughter cells from one parent” but that’s cell division in general. A good strong intro sets the scene for the whole page. Also there are no references for this section.

History: A good start but a few more points would be great, you’re probably coming back to that section anyway.

Body: There is a lot of good text that could be complimented by pictures and diagrams, also some more referencing is needed in sections like contractile ring assembly and contractile ring formation. With the animal and plant cytokinesis section, a table might be good to highlight the similarities and differences between the two.

Current/Future research: It would be great to have some figures to break up the text.

Hey, figure 1 from that Cyk-4 article would go great with the failure bit that I wrote up. Nice find.

--Z3331469 (talk) 22:00, 22 May 2013 (EST)

Hmm, I uploaded two more but they don't seem to show. I might ask Dr. Mark Hill to fix those up if I can't get it going myself. More images to come.

--Z3293267 (talk) 17:56, 19 May 2013 (EST)

You want images! I got you images!

Cytokinesis Student Drawing.jpg RayRappaport.jpg Basic Cytokinesis.jpg Green Urchin Cytokinesis.jpg

As you can see, I found a copyright notice from the Rockfeller University that allows us to use their images. I've taken the one image we can use from wikipedia and I have done the student drawn one too.

NG, check this site See if there's any more images that you like and then you can copy the copyright notice from my other images if you want to upload it to our site.

--Z3293267 (talk) 17:50, 19 May 2013 (EST)

Hey, I have the points of contractile ring and myosin II in mechanisms so I'll be aiming to cover it as best I can there. Same boat with images basically. xx

--Z3331469 (talk) 00:35, 15 May 2013 (EST)

I'm really struggling with finding new images. Copyright is killing me!! Can I get some help with this?

I am making a simple image at the moment. It's a bit rough but should be done soon.

--Z3293267 (talk) 15:44, 12 May 2013 (EST)

SO he did a whole lecture on cell division, how can we fit some of the main points he mentioned about cytokinesis into the project?

  • Division of cytoplasmic contents
  • Contractile ring forms at midpoint under membrane
  • Microfilament ring - contracts forming cleavage furrow
    • myosin II is the motor
  • Eventually fully divides cytoplasm

--Z3293267 (talk) 17:19, 9 May 2013 (EST)

Yo guys, got an idea for how to link it back to what we're learning in the course (marking criteria). The cyto failure article mentions these microtubules: "equatorial astral microtubules, polar astral microtubules and central spindle microtubules", but they're in a paper that can't be accessed (you might have come across it, the Rappaport one). Anyway, we can link the function of these microtubule populations back to the lecture points/if there was anything that came up in the lecture worth mentioning as long as we mention microtubules. Here's a quick article which helps

Also Eugene I think you mentioned something about cyto and cancer? Might have found an article on that that might help, i haven't read through it but the title suggests enough.


--Z3331469 (talk) 17:04, 24 April 2013 (EST)

Select an image related to your selected topic sub-section (this can be from one of the 4 above or from elsewhere). The image should be uploaded (with all the required information: description, reference, copyright and student template) and pasted onto the project page sub-section and onto your own personal page. 400px400px

I found this website that has the milestones in cell division: It's a great website but I just want some opinions just which we should use and not use --Z3293267 (talk) 12:19, 18 April 2013 (EST)

Select 4 reference papers related to your selected topic sub-section. Read these papers and write a brief description of their findings and relevance to the selected topic sub-section. The reference along with your description should then be pasted on both your group discussion page and your own personal page.


<pubmed>20014865</pubmed> This review goes over the basics of what cytokinesis is and discusses the use of small molecule probes to disturb cytokinesis, as well as the role naturally occurring small molecule metabolites such as lipids play during cytokinesis.


<pubmed>4400359</pubmed> This book traces the history of some of the major ideas in the field and gives an account of our current knowledge of animal cytokinesis. It contains descriptions of division in different kinds of cells and the proposed explanations of the mechanisms underlying the visible events. The author also describes and explains experiments devised to test cell division theories. The forces necessary for cytokinesis now appear to originate from the interaction of linear polymers and motor molecules that have roles in force production, motion and shape change that occur in other phases of the biology of the cell. The localization of the force-producing mechanism to a restricted linear part of the subsurface is caused by the mitotic apparatus, the same cytoskeletal structure that insures orderly mitosis.

Current/Future Research

<pubmed>16222300</pubmed> This review discusses how chemical biology approaches have been very useful in understanding different aspects of the mechanism of cytokinesis. In the first part, the article focused on small molecules as biological probes. In addition to their use as probe compounds, however, small molecules also have therapeutic potential. One would expect small molecules that target cytokinesis to be important in the development of cancer therapeutics because improperly regulated cell division can be a cause or a consequence of cancer.

<pubmed>14981513</pubmed> This article shows the use of the mechanism of cytokinesis and develops more small molecule probes targeting different proteins within cytokinesis, anticpating that it will soon be possible to explore the potential drugs of cytokinesis. With the uses of aurora kinase inhibitors, which target both mitosis and cytokinesis, the mechanism cn be used to kill cancer cells.

Cytokinesis Failure

Mutations in twinstar, a Drosophila Gene Encoding a Cofilin/ADF Homologue, Result in Defects in Centrosome Migration and Cytokinesis PMID 8522587

Cofilin is a protein involved in the breaking down of actin filaments during cytokinesis. If these filaments are not dissassembled, cytokinesis failure will occur. This study showed that:

  • in mutant spermatocytes (the test subject for this experiment) defects were found in aster migration and separation during prophase and prometaphase.
  • twinstar mutations encode a Drosophila cofilin homologue
  • F-actin distribution within primary spermatocytes gradually disappears leading up to prometaphase in the wild-type; whereas in mutant primary spermatocytes, F-actin forms a large bundle in the cytoplasm of each cell.
  • Disassembly of actin filaments in mutant primary spermatocytes was delayed heavily during metaphase

APC mutations lead to cytokinetic failures in vitro and tetraploid genotypes in Min mice PMID 17893240

Adenomatous Polyposis Coli (APC) is involved in the formation of the mitotic spindle and the proper functioning of the spindle checkpoint, however, certain mutations of APC induced cytokinesis failure. This study will be helpful as it provides me with another failure of cytokinesis during stage I. The study found that:

  • in cells expressing APC1–1,450 (amino acids 1-1,450), the contact between the cell cortext and microtubules is severely affected
  • unanchored spindles contributed to the failure of cytokinesis in these cells.

Citron kinase controls abscission through RhoA and anillin PMID 21849473

Citron kinase (CIT-K), anillin and RhoA interact during the late stages of cytokinesis, especially in stabilising the midbody. If CIT-K is removed, it is reported in this paper that there is a dramatic loss of anillin and RhoA from the midbody, strongly delaying abscission. This article is helpful as it identifies CIT-K as an essential protein during the later stages of cytokinesis, describing the implications of its removal from test cells in great detail and in relation to RhoA and anillin. This study found that:

  • by removing CIT-K and analysing the localisation of central spindle proteins (RACGAP1, ECT2, Aurora B) and of cleavage furrow proteins (actin, myosin IIB, anillin, and RhoA), there was a disparity in the localization of anillin and RhoA in comparison to the control cells.
  • there is a complete loss of anillin during the late midbody stage at the cytoplasmic bridge in more than two-thirds of the mutated cells.
  • RhoA in the CIT-K depleted cells also showed similar results in terms of delocalisation.
  • by deactivating RhoA in late cytokinesis by means of treating the HeLa cells with a toxin (Clostridium botulinum C3-toxin), the localisation of anillin was greatly affected, but CIT-K remained the same, meaning that RhoA plays a part in the localisation of anillin at this late point in cytokinesis, but not for CIT-K.

Cyk-4 A Rho Family Gtpase Activating Protein (Gap) Required for Central Spindle Formation and Cytokinesis PMID 10871280

CYK-4, an important Gtpase Activating Protein, along with ZEN-4/CeMKLP1 work together in forming the central spindle as well as in regulating RhoA GTPase during cytokinesis. Incorrect formation of the central spindle is a cause for cytokinesis failure. This study identifies a specific protein in relation to that failure. This study found that:

  • cyk-4 mutants (constructed in isolation) do not fully complete cytokinesis. This is shown through the formation of the first cleavage furrow where it forms correctly, ingresses, but regresses soon after.
  • By localising actin and tubilin in both mutant and wild type cyk-4 embryos it was shown that spindles formed during metaphase in the cyk-4 mutant embryos were normal, but during anaphase, significant differences were observed in comparison to the wild type cyk-4 embryos. Microtubule bundles were reduced in size and appeared highly disorganised. Cyk-4 therefore, is required during anaphase for proper formation of the central spindle.
  • It is possible that for this reason, cyk-4 mutant embryos fail to undergo cytokinesis as a result of the failure of the central spindle to be formed.
CIT-K Interaction at the Midbody

--Z3331469 (talk) 09:30, 8 April 2013 (EST)

Some good animations for project

--Z3374087 (talk) 16:13, 28 March 2013 (EST)

Genetic factor HIPK2 controls cytokinesis and prevents tetraploidization by phosphorylating histone H2B at the midbody

Full article not available, will look around for it.

Ras homolog gene family, member A (RhoA) protein regulates actin cytoskeleton; involved in the very first stage of cytokinesis - the specification of the cleavage plane. --Z3331469 (talk) 17:23, 22 March 2013 (EST)

--Z3331469 (talk) 17:00, 21 March 2013 (EST)

Kal Yacoub's section

My topic for group assignment: Process and mechanism of cytokinesis.


Relevance to topic: Investigates the inhibitory effects of particular 'small molecules'. Can use this information to identify factors and biological processes that prevent these inhibitory effects.

Findings: 1990 compounds were obtained from the National Cancer Institute and screened and tested to identify any inhibitory effects on cytokinesis in sand dollar embryos and on single cell wound repair in frog oocytes. It was found that two restriction enzymes in Sph1 and Sph2 reduce Rho (family of G-proteins) activation in wound repair and prevent spindly formation during cytokinesis.


Relevance to topic: Investigates recent research into the particular steps of cytokinesis and the effects of these after it has completed on the next cell cycle.

Findings: Article did not find or prove anything new in particular. It only reinforced common research findings that cytokinesis contributed to anaphase spindle reorganization, division plane specification, actomyosin ring assembly, contraction and abscission. These processes are all integral to completing the final stages of the cell cycle which ultimately allows the two daughter cells to successfully split from one another and undergo their own metabolic pathways.


Relevance to topic:Investigates the effects of C57 in cytokinesis. Relevant because c57 will be an integral part of my description of the cell cycle and this provides great and reliable information in relation to this.

Findings: Lack of Cep57 microtubule distribution and Assembly led to cytokinesis failure of the central spindle. Bi nuclear cells also formed as a result of unnatural distribution of MKLP1, Plk1 and Aurora B. Cep57 was also found to directly regulate the microtubule organization in spindle formation.


Relevance to topic: Research focuses on the metabolic processes that facilitate the completion of cytokinesis. Can use to summarize and finish my description.

Findings: UNC119a activates Src family kinases (SFKs) through a signalling pathway. This is achieved by UNC119a localizing to the centrosome within cells undergoing interphase. After this is translocates from the spindle pole to the spindle mid zone after the subsequent process of mitosis is complete. This process activates the Fyn signal transduction pathway (T cell receptor signaling pathway) to allow cytokinesis to complete.

Image upload:

Image depicting the effect of Rac-mediated activation on cytokinesis inhibition through preventing contractile ring formation and subsequently resulting in bi nucleation of the two daughter cells

Tim Davies, Julie C Canman Stuck in the middle: Rac, adhesion, and cytokinesis. J. Cell Biol.: 2012, 198(5);769-71 PMID:22945931

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