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Arabidopsis transcriptional repressor VAL1 triggers polycomb silencing at FLC during vernalization.

Submitted by oelbetanony on Sun, 12/10/2017 - 18:50

In this paper the authors explored the mechanism of vernalization. Vernalization is the epigenic silencing of FLC. Flowering locus C (FLC) is an important regulator of flowering time. When Arabidopsis Thaliana is exposed to the cold for a prolonged period vernalization is triggered. The Authors sought out to find out what exactly silences this FLC gene in response to prolonged cold exposure. The focus of the paper was what transcriptional factor is specifically responsible in FLC silencing. The authors first determined that PHD-PRC2 was key to the silencing of FLC they then wondered what specific transcriptional factor was responsible for silencing the gene. The authors then Identified a mutant that prevented PHD-PRC2 nucleation which prevented the silencing of the FLC gene. They identified the location of this gene which pointed them to the first pair of RY cis elements. This raised the question of what transcriptional factor was bound to these RY elements and allowed the nucleation of PHD-PRC2 and the silencing of the FLC. To answer this question the authors thought of all the transcriptional factors that could be the key factor and Identified potential key transcriptional factor VAL1 because of its high levels of expression compared to the other candidates. After genetic testing of VAL1 mutants against the wildtype the results showed that VAL1 does bind to the RY elements and also recruits ASAP complex which triggers nucleation of PHD – PRC2 and allows the silencing of the FLC.

Methodological approach to melonopsin study

Submitted by oelbetanony on Sun, 12/10/2017 - 18:49

The Methodological approach consisted of first making antibodies against the C and N terminal of the melonopsin sequence to identify cells in the retina that are.expressing melonopsin. To see where these melonopsin positive RGCs are projecting the authors used Tau-LacZ to target the melonopsin gene. Using Tau-LacZ the authors were hoping to see were melonopsin was activated and projected, and see if it was projected towards the Suprachiasmatic nucleus (SCN) where circadian function is regulated. To make sure all RGCs that are projecting to the SCN are doing so due to melonopsin the authors injected Lucifer yellow into the photosensitive RGCs that projected to the SCN and cross compared with melonopsin antibodies to see if they turned up melonopsin positive. Light was also used to see if these RGCs reacted to it.

education reflection

Submitted by oelbetanony on Sun, 12/10/2017 - 18:45


This class definitely opened my eyes to a lot of things I was never aware of. One of those things is how difficult it is to teach and help students with different learning disabilities, It really takes complete understanding of a students condition to be able to properly help him/her. one thing I realized that I haven't before is how Autism is a spectrum disorder and how it differs greatly from person to person.  



Submitted by oelbetanony on Tue, 12/05/2017 - 10:20

Hemichordates are distingushed by a tripartite segmentation. At the front they have a preoral lobe and behind that is the collar and last comes the trunk. They share some characterstics from the chordates like branchial openings, stomochord, dorsal nerve cord, and a smaller ventral nerve cord. The hemichordates have three different classes. The first class is the Enteropneusta, they are referred to as acorn worms and they use proboscis to burrow through sediment. Pterobranchia is another class which is characterized by how the individuals of the class form colonies. Graptolithina is the last class which is already extinct, their fossils are found in ordovician and silurian rocks.

Esterification and IR

Submitted by oelbetanony on Tue, 12/05/2017 - 10:04

The starting materials were reacted using conditions specific to the reaction being performed and the target product was obtained in a good yield but there was a lot of water in the yield. The % yield of the product was 61%. Assumptions about the procedure that were made can include that the compounds were all relatively pure and did not contain impurities in the separation. The IR spectroscopy showed peaks at 2958, 1743, 3400, and 1244 (1/cm). The peak around 3400 shows that there was water in the mixture. There was a sharp peak around 1740 that shows the presence of an ester. The IR spectroscopy shows that there was a successful separation of an ester. One source of error that could have lead to water not being completely is that the calcium spheres weren’t applied enough.  If the experiment were to be redone, the proper amount of calcium spheres would have been added and properly swirled until there was no water left. Furthermore, there should be a more affective reflux method so that there can be a higher guarantee of the separation of water. Overall, the identity and purity of the product was assessed and there was successful separation of the ester.


ASD and self determination

Submitted by oelbetanony on Tue, 12/05/2017 - 10:03

Doug and Tomas are both autistic but both need assistance in a lot of things in there life but they exhibit independent living in most of the things that they do. Doug shows independent living by being able to have and maintain a job. Tomas also shows independent living by living on his own in the absense of his family. Autism is called the spectrum disorder because people with autism all differ with they are able to do and what they need assistance with. One way educators could have improved self determination for Doug and Tomas when they went to school would  be letting them  choose which way they prefer to learn and by helping them set and achieve goals and everyday objectives.

The gate theory of pain

Submitted by oelbetanony on Wed, 11/29/2017 - 15:01

The gate theory of pain suggests that there is an inhibitory interneuron that inhibits the projected neuron that carries pain signals to the brain when there is also touch sensory input at the same time. This interneuron is excited by touch sensory input thats why when you stub your toe you immediatly grab your foot, which excites this inhibitory neuron that then inhibits the projecting neuron carrying pain signals to the brain and the pain is mediated. 

The cortical module

Submitted by oelbetanony on Mon, 11/27/2017 - 10:02

Hubel and weisel argued that a 2x2 mm chunk of striate cortex is both necessary and sufficient to analyze the image of a point in space. Necessary because its removal would leave a blind spot for this point in the visual field , and sufficient because it contains all the neural machinary required to analyze the form and color of objects seen through the eyes.  

Deaf culture

Submitted by oelbetanony on Mon, 11/27/2017 - 09:56

I understand that there is a culture for people that are deaf, after all its all that they have ever known and maybe most of them never have the desire to hear because of it. Culture is defined as the ideas, customs, skills, and arts of a given people in a given period, and a common language is generally accepted as necessary to share these aspects of the culture, in this case its sign language. While I recognize that side and belief and see and appreciate that culture I do not think cochlear implants take away from the deaf community. I do understand that if one was deaf for most of their life and deafness has become part of who they are and have no desire to hear even if given the opportunity that it is a reasonable decision which I completely understand. What I do not agree with is if one who is deaf had a deaf child and decides not to give them the ability to hear solely on the fact that they think it would "exclude" them from the deaf community and ultimately making that decision in the child's "best interest". Not only do I think that is just wrong its also not fair for the child. I believe if given the opportunity regardless of your state, experiences, or quality of life you should always give children the best quality of life ESPECIALLY if you are able too. Sometimes you are dealt a tough card in life in which there is nothing you can do but make the best of it, and try to live with what you do have but if there is something you can do and you can protect a child from something like that it shouldn't even be a question.  Just because you lived with an impairment and maybe discovered the beauty of the community it forged at the end of the day its still a lesser quality of life that in turn made a community characterized and unique because of an impairment. So while I don't think cochlear implants are a needed tool for all deaf people, hearing is still something you shouldn't spare a child regardless of your opinion and own experiences. I also don't think cochlear implants interfere with the deaf community. Deaf people have come a long way to change the idea of deafness from a disability to a culture full of meaning and beauty but cochlear implants are not devaluing the culture, its devaluing the impairment that is deafness. At the end of the day deaf or not we are all part of a bigger community, the moral community and its our moral duty to give everyone the best quality of life if we can.     


Vernalization-Triggered Intragenic Chromatin Loop Formation by Long Noncoding RNAs.

Submitted by oelbetanony on Tue, 11/07/2017 - 18:26

In this paper the authors wanted to study the non coding RNAs that are involved in Vernalization. One known group of non coding RNAs are called COLDAIR. The authors started by using RNA immunoprecipitation (RIP) to examine the dynamics of COLDAIR. Upon doing this the authors stumbled upon additional RNAs in the promotor region of FLC and named them COLDWRAP. Upon further observation they discovered that COLDWRAP is also expressed after prolonged cold exposure but unlike COLDAIR it stays expressed even after exposure to cold. It was also discovered that COLDWRAP plays a major role in forming an intragenic chromatin loop making COLDWRAP necessary for vernalization.


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