polypeptides

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Walz of the Polypeptides by Mara G. Haseltine

Haseltine on her project:

The inspiration for Waltz of the Polypeptides (2003) comes from one of the smallest muses on the planet, a subject so tiny it can only be seen with an electron microscope. It is a sub-cellular organelle called a rhibosome. Within each cell, ribosomes produce the smallest functional elements in all living organisms, proteins. In Waltz of the Polypeptides the viewer literally walks through the birth of a single protein.

To create this work, Mara G. Haseltine studied the ribosomes and proteins and used accurate molecular renderings of electron microscopic and nuclear magnetic resonance images for her armatures. She manipulated this raw data using a 3-D computer program into a design which kept the integrity of Mother Nature’s form while simultaneously creating a work that was comprehensible and pleasing to its viewers. She then fabricated this design into three-dimensions using computer-driven 5-axis milling and rapid prototyping technologies. The work itself was created to be part of a living landscape inspired by the Zen gardens of Kyoto. Each part of the landscape represents a different part of the cell. Thus, when the viewer experiences Waltz of the Polypeptides, they are fully immersed into a fantastical environment based on a tiny part of the human body.

(h/t Alyson Swimm)

Molecular model of a ribosomeWellcome Images

Molecular model of a bacterial ribosome showing the RNA and protein components in the form of ribbon models. In the large (50S) subunit the 23S RNA is shown in cyan, the 5S RNA in green and the associated proteins in purple. In the small (30S) subunit the 16S RNA is shown in yellow and the proteins in orange. The three solid elements in the centre of the ribosome, coloured green, red and reddish brown are the transfer RNAs (tRNAs) in the A, P and E sites respectively. The anticodon loops of the tRNAs are buried in a cleft in the small subunit where they interact with mRNA. The other ends of the tRNA, which carry the peptide and amino acid, are buried in the peptidyl transferase centre of the large subunit, where peptide bond formation occurs.

VIP treatment for jet lag

A brain chemical that desynchronizes the cells in the biological clock helps the clock adjust more quickly to abrupt shifts in daily light/dark schedules such as those that plague modern life.

A small molecule called VIP, known to synchronize time-keeping neurons in the brain’s biological clock, has the startling effect of desynchronizing them at higher dosages, said a research team at Washington University in St. Louis.

Far from being catastrophic, the temporary loss of synchronization actually might be useful.

Neurons knocked for a loop by a burst of VIP are better able to re-synchronize to abrupt shifts in the light-dark cycle such as those that make jet lag or shift work so miserable. It takes tumbling cells only half as long as undisturbed cells to entrain to the new schedule, the scientists say in the Oct. 28 online early edition of the Proceedings of the National Academy of Sciences.

Resynching by jarring is familiar to everyone who has whacked a flickering analog TV to get it to sync or hit the ceiling near a fluorescent light in the hope that its ballast starts buzzing.

The scientists hope to find a way to coax the brain into releasing its own stores of VIP or to find other ways to deliberately cause tumbling so the body’s clock will reset to a new time. Such a treatment might help travelers, shift works and others who overtax the biological clock’s ability to entrain to environmental cues.

The finding is the latest to emerge from the lab of Erik Herzog, PhD, who has studied the body’s time-keeping mechanisms for 13 years at Washington University in St. Louis. His focus is on understanding the clock, but because most of us live against our biological clocks and research shows this leads to health problems ranging from obesity to depression, his work is likely to have practical payoffs.

Timing is everything

The master circadian clock in mammals is a knot of 20,000 nerve cells roughly the size of a quarter of a grain of rice called the suprachiasmatic nucleus (SCN). Each neuron in the SCN keeps time, but because they’re different cells, they have slightly different rhythms. Some run a bit fast and others a bit slow.

“They’re like a society where each cell has its own opinion on what time of day it is,” said Herzog, a profesor of biology in Arts & Sciences. “They need to agree on the time of day in order to coordinate daily rhythms in alertness and metabolism.”

The cells talk to one another through a molecule called VIP (vasoactive intestinal polypeptide), a small string of amino acids that they release and receive. It’s through VIP that cells tell one another what time they think it is, Herzog said. If you get rid of VIP or the receptor for VIP, the cells lose synchrony.

“We were trying to understand exactly when VIP is released and how it synchronized the cells,” Herzog said, “and Sungwon An, then a graduate student in my lab, discovered that when there was extra VIP around, the cells lost synchrony.

“That was really surprising for us,” he said. “We did a lot of experiments just to make sure the VIP we had bought wasn’t contaminated in some way.”

It turned out the effect was real. Above a critical level, the more VIP was released, the more desynchronized the cells became. “It’s almost as if at higher doses the cells become blind to the information from their neighbors,” Herzog said.

“Then we thought: ‘Well, if the cell rhythms are messed up and out of phase, the system may be more sensitive to environmental cues than it would be if all the cells were in sync.’” If it was more sensitive, it might be better able to adjust to the abrupt schedule shifts that characterize modern life.

They were encouraged in this line of thinking by a simulation of the SCN created by Linda Petzold, Kirsten Meeker, Rich Harang and Frank Doyle, all chemical engineers at the University of California, Santa Barbara. The numerical model predicted that increasing VIP would lead to phase tumbling (less synchrony) and accelerated entrainment.

Rapid entrainment to environmental cues is important, Herzog explained. The master clock has evolved to adjust to slow seasonal changes in light/dark schedules, but not to abrupt ones that are built into the fabric of modern life. Even the seemingly benign one-hour shift for daylight savings time increases the risk of fatal car crashes and of heart attacks.

“We were curious to see whether adding extra VIP would improve the ability of biological clocks to make big adjustments,” Herzog said. An, together with graduate student Cristina Mazuski and research scientist Daniel Granados-Fuentes, showed that a shot of VIP did in fact accelerate entrainment to a new light schedule.

“We found that in mice we could cut ‘jet lag’ in half by giving them a shot of VIP the day before we ‘flew them to a new time zone,’ by shifting their light schedule,” Herzog said.

“That’s really exciting, “ Herzog said. “This is the first demonstration that giving a bit more of a substance the brain already makes actually improves the way the circadian system functions. “

“We’re taking the system the brain uses to entrain to changes in the seasons and goosing it a bit so that it can adjust to bigger shifts in the light schedule,” he said.

“We’re hoping we’ll be able to find a way to coax the brain into releasing its own stores of VIP or a light trigger or other signal that mimics the effects of VIP,” Herzog said.

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Looks like I’m pretty late to the game but I was tagged by the wonderful bite-me-karnstein ! Thank you! :) And I think we were suppose to take “fresh” selfies but these are the most recent ones of me right now.

The 20 I will be tagging are:
ahahahahans always-aaack-for-everlark basicallyqueenelsa digging-thegrave goodbyemydearvictoria i-am-the-real-ada-wong kristoffarendele legolas-throne lizeth916 lolhahahano queen-thirrin reign-of-thranduil rose-merida sailorcar the-bumbling-polypeptide thorinshielding very-pallid-and-aghast
And anybody else that wants to do it :)

Researchers identify amyloid formation link between Alzheimer’s disease and T2 diabetes. Thoughts health innovators?

The pathological process amyloidosis, in which misfolded proteins, amyloids, form insoluble fibril deposits, occurs in many diseases, including Alzheimer’s disease and type 2 diabetes mellitus.

S²→S¹: Input a point on a sphere, output a point on a circle

[An] instance of such maps occurs in the crystallization of synthetic polypeptides and polynucleotides (artificial analogues of biological proteins and genetic material). Such substances are fibrous, giving to each point on the surface of a crystalline ball (S²) an orientation. The orientation may be specified as a point on an abstract sphere (S²) or, given that the fiber lies in the plane of the surface, on an abstract ring (S¹) of compass directions. There is no way to carry out such a map smoothly. There must be at least one point of confused orientation. These points are clearly visible by polarized light microscopy.
— 

Arthur Winfree, The Geometry of Biological Time. Springer, 2000. Ch. 1 - Circular Logic

see Robinson, 1966; Wilkins, 1963; Anderson et al., 1967.

I would have received a 100 on my cell biology test but I made stupid mistakes. like Polypeptide is almost synonymous with protein so obviously there are peptide bonds in it… 

New Post has been published on WomanHealthGate

New Post has been published on http://womanhealthgate.com/mystery-melatonin-pineal-gland/

The mystery of Melatonin and Pineal Gland

the localization of the Pineal Gland

I started my interest in Melatonin (a polypeptide hormone produced by the Pineal Gland) when I was an intern at Ancona University (Italy). At that time I was interested in chronobiology and interactions between environment and neuroendocrine – reproductive system.

The Pineal Gland (also called Epiphysis) is a small endocrine gland located behind the third ventricle and below the Corpus Callosum, practically in the brain center. It’s connected to the surrounding brain structures but mainly receives nerve fibers from the suprachiasmatic nucleus of the Hypothalamus through the Autonomomic Nervous System.

The suprachiasmatic nucleus of the Hypothalamus is considered one of the main centers of biological internal clock regulation and it is directly connected to the retina nerve fiber and therefore to information on ambient light variations. The Epiphysis is therefore a typical neuroendocrinal structure (such as the Adrenal Gland) where the nerve signal (alternating of light / dark) is translated into a message influencing Melatonin secretion in a circadian manner.

Its particular anatomical location still fuel many suggestions about its role. For example, in the sixteenth century Descartes placed here the seat of the soul. In 1899 it is started to assume a functional connection with the endocrine hypothalamus-pituitary-ovary axis and this was done thanks to Ogle and Heuber.

Melatonin secretion is strongly affected and it is strictly dependent of day-night (light-dark) rithm, taking in the

Melatonin night-time levels tend to decrease with age

blood a typical circadian cycle with higher levels during the night and lower during the day. Telling the truth, there also are a hormone seasonal variations and in women was demonstrate a variation in the night peak related to menstrual cycle (with lower levels in the peri-ovulatory period) and additional regulatory signals originate from other hormones (such as those ovarian and adrenal hormones).

Bloud Melatonin levels tend to decrease progressively with age.

Here are main actions attributed to Melatonin, outside legends or myths artificially constructed.

REPRODUCTIVE FUNCTION:

- The action is substantially antigonadotropic. The Pineal Gland has an important inibitory role on sexual development until puberty. Pineal Gland tumors were associated with precocious puberty. In some small animals it regulates seasonal reproductive rhythms and can not be excluded that in women could cooperate with regulating menstrual and ovulation systems.

Secretory abnormalities have been described in hypothalamic and stress amenorrhea. It is not excluded that many ovulatory disorders may be related to an alteration of its circadian rhythm.

Very interesting the recent use of Dietary Supplements containing Melatonin, Myo-Inositol and Folic Acid in premature ovarian failure (POF) and ovulation induction: in fact, this compounds showed to improve ovarian response in cycles of ovulation induction and in some forms of ovarian insufficiency.

INSOMNIA, ENVIRONMENTAL ADAPTIVE DISORDERS:

- While Melatonin is not the main regulator of sleep is undeniable nonetheless its ability to induce sleep (reduction of the latency time before falling asleep); also seems to improve the quality of sleep itself and has been used with success in the treatment of Insomnia;

- It plays an important role in the environmental adaptive disorder like in journeys which involve significant changes in timezone. Administration of melatonin is the best pharmacological remedy to combat symptoms classified under the “jet lag disorder “;

- It is effective in combating disorders such as fatigue and a feeling of malaise resulting from disruption of normal sleep cycle – wakefulness (light – dark) – resulting for example in repeated rounds of night work; many give to secretion of melatonin a function of pacemakers (system controller) and other metabolic and hormonal functions.

- It is involved in almost all branches of medical science, ranging from Aging (anti-oxidant effects) to Oncology, from Cardiovascular diseases to immunology, but regard these fields of medicine are needed more and more scientific evidence.

- Aging;

- Night exposure to light;

- Use of certain antihypertensive adrugs, anti-inflammatory drugs, tranquilizers (Benzodiazepines);

- Dietary deficiency of Tryptophan (an essential amino acid), alcohol abuse, use of coffee at night.

Melatonin is available as dietary supplements and is taken orally during the evening (after dinner) at a dose between 0.5 and 4 mg. Safety profile (when using in short-term) is very good, nevertheless its use in my opinion should always be done under medical indication. Too much in fact we still need to know about this hormone, and everything that comes promote not always correspond to scientific evidence.

AP Bio Pickup Lines

Hey are you a start codon? because you’re turning me on.

Are you an amino acid? Because you’re making my polypeptide chain longer and longer.

If I were an enzyme, I’d be DNA helix see so I could unzip your genes.

If I were a nucleotide I’d be adenine so I could pair with U.

Journal of Clinical Research and Ophthalmology is an open access, a peer reviewed, online, international, scientific and elevated scope journal which covers most up-to-date and outstanding research works/top quality papers on the entire spectrum of ophthalmology, including prevention, diagnosis, treatment, toxicities of therapy, supportive care, quality-of-life, and survivorship issues.

The neuropeptide research in the eye is the main topic of our scientific group in Innsbruck. Most of the neuropeptides have been discovered more than 30 years ago and the presence and distribution of some of them has been explored in the eye in the 80´s mainly by Richard Stone. This concerns particularly substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP) and neuropeptide Y (NPY). Whereas SP and CGRP have been found to be constituents of the sensory innervation of the eye, VIP is present in the parasympathetic and NPY in the sympathetic innervation of the eye.

http://www.peertechz.com/Clinical-Research-Ophthalmology/JCRO-2-115.php

How is the membrane protein folded? From molecular biology toward new medical care
A key factor in the biosynthesis and stable expression of multi-pass transmembrane proteins has been discovered, and its loss is thought to cause retinal degeneration. The factor works especially for multi-pass membrane proteins, in the integration of polypeptides into the membrane and/or protein folding. Understanding the mechanisms underlying protein folding and trafficking may contribute to the large-scale, therapy-based production of target proteins.





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March 02, 2015 at 09:02AM