Excerpts from Recent Articles from 2004

2004 Back Issues

Bio-Art - December 2004
Proteins have made it into the world of Art! In 2002, Julian Voss-Andreae – a physicist cum artist –used a Protein Spotlight article as a source of inspiration for one of his sculptures. The protein he chose to sculpt was Kalata B1, a polypeptide with a very special twist in its sequence which forms what is known as the Moebius strip. Kalata was not the first protein Julian undertook to portray, nor would it be the last. Green fluorescent protein (GFP), mating pheromone ER-1, light-harvesting complex and a viral capsomer have also been moulded by the artist’s hands, not to mention a homage paid to the man who discovered the alpha helix structure by erecting a huge replica in front of the scientist’s boyhood home – now known as the Linus Pauling Center for Science, Peace and Health. (PDF version - 216K bytes)
Swiss-Prot cross references
Green fluorescent protein, Aequoria victoria (Jellyfish): P42212
Kalata B1, Oldenlandia affinis : P56254
Nature's philanderers - November 2004
Could chemistry be at the heart of sexual wanderings? Or of sexual devotion? Though the idea certainly lacks romantic appeal, there are signs which point in this direction. The neuropeptide vasopressin is not a newcomer to research on animal social behaviour. However, narrowing one of its roles down to what scientists coolly term ‘social cohesion’, and Christians call ‘infidelity’, is a breakthrough, and deserves some thought. It is not so much the quantity of vasopressin but the tissue distribution of its receptor – in males - which seems to have a role in defining flirt or faithfulness. (PDF version - 80K bytes)
Swiss-Prot cross references
Vasopressin V1a receptor, Microtus montanus (Montane vole): Q9WTV8
Vasopressin V1a receptor, Microtus ochrogaster (Prairie vole): Q9WTV9
Talking heads - October 2004
Humans can talk. Other animals cannot. So there must be something inside us that is quite particular to the species. Certainly, the human larynx is placed in such a way that it supports our vocal miracles. But the positioning of the larynx itself is not at the heart of our capacity to form words, nor to learn them, remember them, reproduce them and place them in an order which makes sense to our listeners. All this demands neuronal as well as motor facilities, which are unique to humans. Could the art of speech be genetic? ‘Well…kind of’, say researchers. There certainly seems to be growing evidence that the human faculty of vocal communication bears a genetic component. And who says gene, says protein… FOXP2, a transcription factor, was discovered a few years ago and, though its exact function remains unknown, it is now quite certain that it participates in human language skills. (PDF version - 233K bytes)
Swiss-Prot cross references
Forkhead box protein P2, Homo sapiens (Human): O15409
A virus for life - September 2004
Who would have thought that a virus could have anything to do with a tissue as important to life, and its development, as the placenta? A viral protein, now known as syncytin, whose gene was probably integrated into the primate genome over 25 millions years ago, is hugely expressed in placental tissue – especially at the beginning of embryonic development – and is giving signs of bearing an essential role in placental architecture. Could it be that placental evolution – and indeed mammalian evolution – finds its origins in the doings of a virus? (PDF version - 132K bytes)
Swiss-Prot cross references
Syncytin, human endogenous retrovirus-W (HERV-W) Homo sapiens (Human): Q9UQF0
Snowy stardom - August 2004
One higher primate gained recognition for being sent up into space, another for memorising language signs and yet another for saving the life of a young boy. But none of them reached the heights of fame the albino gorilla ‘Snowflake’ reached: Snowflake was the first case of albinism in great apes ever recorded. He suffered from the well-documented pathology: oculocutaneous albinism type 1 (or OCA1). This type of albinism is the most common form in humans and is caused by the malfunction of a tyrosinase, an enzyme which has a key role in the synthesis of the pigment melanin. (PDF version - 52K bytes)
Swiss-Prot cross references
Tyrosinase, Gorilla gorilla gorilla (Lowland gorilla): Q9BDE0
One beer please - July 2004
Beer has been around for thousands of years. Beer foam has not. Beer foam, as indeed beer haze, is one of today’s hot topics in the world of beer brewing. Besides a beer’s taste of course. What a beer should look like – once served in a glass – has become paramount for a brand’s commercialization. And that is why there has been much bustle around the chemistry at work in such a process. It has been known for a while now that a number of proteins, or more correctly polypeptides, are involved in foam formation but it wasn’t possible to pinpoint which protein was more involved than another. Finally, it appears that one barley protein has managed to wriggle out of the crowd. And what might that protein be? Lipid Transfer Protein 1 or LTP1. (PDF version - 59K bytes)
Swiss-Prot cross references
Lipid Transfer Protein (LTP1), Hordeum vulgare (Barley): P07597
Mad yeast disease - June 2004
When referring to prions, most of us think ‘Mad Cow disease’ (Bovine Spongiform Encephalopathy or BSE). Which is not incorrect but narrow-minded. The term ‘prion’ – coined in the early 1980s by the American biochemist Stanley Prusiner – simply means ‘infectious protein’, from which were derived the letters which make up the word. Prion proteins are found not only in cattle, sheep and humans, but also in other vertebrates as well as yeast and certain fungi. And will no doubt continue to be discovered in many other organisms, if not all. The URE2 protein – a candidate prion in Saccharomyces cerevisiae – was the first prion to be crystallised. Clearly, the understanding of a prion’s 3D structure and the conformational changes it undergoes – and passes onto its peers – is of great interest in the search for therapeutic treatments of diseases caused by these volatile proteins. (PDF version - 482K bytes)
Swiss-Prot cross references
URE2 protein, Saccharomyces cerevisiae (Baker's yeast): P23202
A small blast from the past - May 2004
'What's a fossil Mum?’ To which most Mums would answer, ‘A fossil, sweetie, is bone which has become stone because it’s been lying somewhere for a very long time.’ The process of bone diagenesis is a complicated one but on the whole Mum’s answer is not incorrect. However, before the bone becomes absolute stone and depending on the environment, some organic parts can survive for a long time. Even millions of years. And these are excellent candidates for study. Scientists have already managed to extract DNA from fossil bone – though in poor condition. Which is a pity, because DNA – though minute – can stash huge amounts of information. What is needed is something that not only lasts but is also informative from a biological point of view. A protein perhaps? (PDF version - 96K bytes)
Swiss-Prot cross references
Osteocalcin, Bison priscus (Steppe bison): P83489
Protein wars - April 2004
Face-to-face combat also exists at the molecular level. With time, animals have developed the means to fight off foreign bodies by way of a complex immune system. But it can be countered. Recently, it was discovered that the defensive effects of one protein (APOBEC3G) – found mainly in human T lymphocytes – could be wiped out by the actions of a second viral protein (VIF) which neutralises it. The net result is viral infection of human T lymphocytes. VIF belongs to Type 1 Human Immunodeficiency Virus (HIV-1) and seems to be crucial for the development of viral infection; whilst APOBEC3G, without the counter-effects of VIF, can ward off HIV-1 infection on its own. The great interest is that novel therapies developed around APOBEC3G and VIF should be of tremendous help in the endless struggle to design drugs which could fight off HIV-1 infection effectively. (PDF version - 439K bytes)
Swiss-Prot cross references
APOBEC3G, Homo sapiens (Human): Q9HC16
What mosquitoes sniff - March 2004
It is hardly the time to talk of mosquitoes when the cold winter winds are still blowing. In milder climates though, mosquitoes are out and about, causing millions of deaths every year through their ability to transmit diseases, such as encephalitis, dengue, yellow fever and, of course, malaria. According to the World Health Organization, malaria alone is the cause of over two million deaths in Africa, one million of which are children under the age of five. The mosquitoes that transmit the disease belong to more than one species and they are collectively known as the anopheline mosquitoes. (PDF version - 33K bytes)
Swiss-Prot cross references
Odorant receptor Or1, Anopheles gambiae (African malaria mosquito): Q8WTE7
Miniature masonry - February 2004
Ever heard of diatoms? Diatoms are phytoplanktonic unicellular algae that populate soil and seas around the globe. They are so small that many are indistinguishable under the light microscope – with dimensions ranging from a few micrometers to only a millimetre. Yet despite their microscopic size, diatoms are one of our primary sources of oxygen. Which just goes to show that minute can also spell merit. There has been a growing interest in diatoms – or their exoskeleton – in the past decade because they display the most intricate bioarchitecture ever seen…and in glass, if you please. The glass shells that surround the microalgae are nourishing the imagination of nanotechnologists. And diatomists are just beginning to decipher the molecular mechanisms underlying diatom shell masonry. One of the masons is called silaffin. Silaffins were discovered in the diatom Cylindrotheca fusiformis; they are an intimate part of the diatom glass matrix and are endowed with architectural talents. (PDF version - 258K bytes)
Swiss-Prot cross references
Silaffin 1, Cylindrotheca fusiformis : Q9SE35
The Bubble's Bend - January 2004
Bubbles are not reserved to the likes of champagne or beer. Our cells also sprout bubbles – or vesicles. Vesicles are formed by means of two cellular processes: exocytosis and endocytosis. The point of such bubbles in living organisms is to relieve the plasma membrane of a number of constituents. Be it to down regulate a pathway – by removing a given receptor from the plasma membrane for example – or to transport molecules from one side of a cell to another. One species of vesicle – the clathrin-coated vesicles – are particularly important in vesicle trafficking in endocytosis and in exocytosis. And in the process of endocytosis, one protein – epsin – has a major role in the initial steps of membrane budding. (PDF version - 29K bytes)
Swiss-Prot cross references
Epsin1, Homo sapiens (Human): Q9Y613
Epsin1, Rattus norvegicus (Rat): O88339


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