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An article that uses the design concept effectively?


A friend writes to tell me that this article uses the design concept effectively. What do you think?

ASAP Biochemistry, ASAP Article, 10.1021/bi800357b
Web Release Date: June 19, 2008
Copyright © 2008 American Chemical Society
11-cis- and All-trans-Retinols Can Activate Rod Opsin: Rational Design of the Visual Cycle†
Masahiro Kono,* Patrice W. Goletz, and Rosalie K. Crouch
Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina 29425
Received February 29, 2008
Revised Manuscript Received May 25, 2008

Rhodopsin is the photosensitive pigment in the rod photoreceptor cell. Upon absorption of a photon, the covalently bound 11-cis-retinal isomerizes to the all-trans form, enabling rhodopsin to activate transducin, its G protein. All-trans-retinal is then released from the protein and reduced to all-trans-retinol. It is subsequently transported to the retinal pigment epithelium where it is converted to 11-cis-retinol and oxidized to 11-cis-retinal before it is transported back to the photoreceptor to regenerate rhodopsin and complete the visual cycle. In this study, we have measured the effects of all-trans- and 11-cis-retinals and -retinols on the opsin’s ability to activate transducin to ascertain their potentials for activating the signaling cascade. Only 11-cis-retinal acts as an inverse agonist to the opsin. All-trans-retinal, all-trans-retinol, and 11-cis-retinol are all agonists with all-trans-retinal being the most potent agonist and all-trans-retinol being the least potent. Taken as a whole, our study is consistent with the hypothesis that the steps in the visual cycle are optimized such that the rod can serve as a highly sensitive dim light receptor. All-trans-retinal is immediately reduced in the photoreceptor to prevent back reactions and to weaken its effectiveness as an agonist before it is transported out of the cell; oxidation of 11-cis-retinol occurs in the retinal pigment epithelium and not the rod photoreceptor cell because 11-cis-retinol can act as an agonist and activate the signaling cascade if it were to bind an opsin, effectively adapting the cell to light.

The rest of the article is in Paywall City. If you’re from there, read and spill.

Also, new at the Post-Darwinist:

Could life on Earth be much older than supposed?

Evolve already, huffingtons … the alligators are laughing at you

What happens when we assume there is no design in nature …

More on Louisiana’s “assault on Darwin” …

Darwin’s co-discoverer thought design can be detected in nature

History moment: Quick, relabel that exhibit!

“Accepting evolution” does not make you an atheist… oh, puh-LEASE! Not this rubbish again!

Hey, guys, we need more humour! I got Landru's joke, but in fairness I have been splitting a gut recently. Canada's "social worker" fascism (= "human rights" commissions) has recently made the mistake of charging a late nite comic with inappropriate jokes, and we are now organizing a huge laugh-in at the "human rights" commissions expense: See: Comics rally for freedom: Let's LAUGH Canada's "human rights" commissions out of existence! Did you know that you have a human right to be bored silly? To be protected from anything that you think is funny? No? Oh, good. Wish us well, then. - d. O'Leary
Really sorry, I honestly didn't think joking reference to the inverted retina argument needed citation or anything. I thought I had a good feel for this blog reading it over the years now, and while it looks like I may have misjudged, I would not jump in lightly to a blog of this quality without consideration. For the record, and to complete full disclosure in case there is any confusion remaining, by "good" I meant, jokingly and sarcastically, that my parody was so "good" that it appeared to have been taken seriously. Again, my strongest apology to you, jerry, for doing this at your expense. landru
landru, I thought it was funny. Showing us again how Darwinism is beyond criticism, admits no unexplained anomalies, and is supported by whatever evidence is found. Lutepisc
"Good" is regurgitating bad arguments without providing the information that also refutes it? I see that your attempts at parody are consistent: https://uncommondesc.wpengine.com/intelligent-design/another-icon-of-bad-design-bites-the-dust/#comment-119584 Here's the info on the inverted retina: http://www.detectingdesign.com/humaneye.html#Optical BTW, if the front-loaded scenario is correct I believe we should not expect the loaded implementations to be optimal in all respects. For example, the octipi with with their verted retinas provides significant advantages based on the needs of its owner. But fish are in the same environment, yet for some reason they have inverted retinas. Explicit Designer choice or a front-loading mechanism that is based upon environmental triggers, timed triggers, and/or pseudo-randomness? Patrick
Jerry, My post was parody, and I'm sorry I prolonged the confusion and had fun at your expense with the followup sarcasm. landru
"Dang, I’m good!" No, the proper description is consistent. jerry
Dang, I'm good! landru
landru, You have listed some supposedly inferior examples of design, thus using the negative argument against design. You are attempting to undermine the design argument through examples judged by you to be inferior design. Darwin did the same to justify his ideas. Since Darwin, no one including Darwin himself has been able to provide positive evidence for his ideas other than for micro evolution. Negative information rules the day among those who support Darwin. Thank you for making the anti Darwin case for macro evolution for us. You are entirely consistent with all your predecessors. jerry
Clumsily or haphazardly arranged sytems like the backwards retina? Maladapted, failure-prone systems like the human back, childbirth that often kills the mother? Vindication of Darwin! Elegant, optimized sytems like this that appear to rationally solve design problems? More evidence of the power of evolution! landru

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