Talk:2013 Group 2 Project

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Revision as of 17:22, 22 May 2013 by Z3330409 (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.

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?

History

  • 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?

Mechanisms

  • 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

  • NEEDS CITATION
  • 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

Introduction:

  • 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

History

  • 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

Mechanisms:

  • 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.



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 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2175131/. 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

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3593075/

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.

http://www.sciencedirect.com/science/article/pii/S0014579310002644

Nobs

--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: http://www.nature.com/celldivision/milestones/index.html 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.

Introduction

<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.

History

<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 http://bement.molbio.wisc.edu/node/13

--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.

http://www.ncbi.nlm.nih.gov/pubmed/22658722

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)

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3063936/

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


Kal Yacoub's section

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

<pubmed>23125193</pubmed>

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.


<pubmed>22552143</pubmed>

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.


<pubmed>23569207</pubmed>

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.


<pubmed>23535298</pubmed>

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

Note - This image was originally uploaded as part of a student project and may contain inaccuracies in either description or acknowledgements. Please contact the site coordinator if the uploaded content does not meet the original copyright permission or requirements, for immediate removal.