Catarina Amorim

A research team in Portugal and the US has found for the first time nicotine receptors in the taste buds. In fact, although most of the toxicity of smoking is linked to other components, it is nicotine that leads to smoking addiction and until now it was believed that this substance had to migrate into the brain to bind its specific receptors and provoke its effects.

Asymmetry is crucial for the heart proper functioning, and now, scientists from the Institute Gulbenkian of Science in Portugal and Harvard University, have discovered that a family of genes, called Nodal, is crucial determining this asymmetry by controlling the speed and direction of the heart muscle cells during embryonic development.The finding, by helping to understand how the heart develops, is a step closer to intervention and is of particular importance if we consider that problems in heart asymmetry are the main cause of heart congenital diseases that can affect as much as 8 out of 1000 newborns. The research appears in a special December issue of the journal Development Dynamics 1 dedicated to left-right asymmetry development.

The Iberian Lynx is now the most endangered cat in the world with only about 160 animals remaining in the wild and, despite extensive research and millions of Euros spent in decades of protection, nothing seems capable to stop this decline.

Scientists in Cambridge, UK, using a mouse with a human chromosome in its cells, discovered that gene expression, contrary to what was previously thought, is mostly controlled by regulatory DNA sequences. Mice and humans (and most vertebrates) share the majority of their genes but a distinct gene regulation – so, when and where these shared genes become activated – assures their many individual characteristics, and knowledge of this regulation is crucial if we want one day to be able to control gene expression.

A new improved gene therapy can be the first treatment for Machado-Joseph disease as  Portuguese, Swiss and French researchers show, for the first time, that is possible to inhibit in a living organism the mutated copies of a gene, without affecting any existing normal copies of the same gene. The research, to appear in the 8th of October edition of the journal PLoS One, describes how scientists successfully used the approach in rats to reverse the symptoms of Machado Joseph Disease (MJD), an untreatable and potentially fatal neurodegenerative disease. 

For a long time scientists have been puzzled by the fact that the immune system in the gut is capable of fighting toxic bacterial infection while staying, at the same time, tolerant to its resident “friendly” bacteria. But an article now published in the journal Cell Host & Microbe(1) is starting to open the door to this mystery by revealing how a recently discovered gene - pims – is activated by the gut immune response against friendly bacteria to rapidly suppress it, effectively creating tolerance to the gut microbiota.

In the same way pims is also shown to control the magnitude of immune responses against toxic bacteria by suppressing immuno-reactivity when a certain activation threshold is achieved, assuring, in this way, that the response stays restricted to the infection site and is proportional to the extent of the infection. These results suggest that the balance tolerance/immuno-reaction in the gut is achieved through self-regulatory cycles where suppression by negative regulators, such as pims, is triggered as soon as a specific threshold of immuno activation is reached.

The architecture of haematopoiesis – which is the process by which all blood cells originate – is essentially the same throughout the mammal world, report scientists in the Proceedings of the Royal Society.

This is an unexpected result considering the thousands of mammals’ species with a myriad of habitats and lifestyles, as so well demonstrated when comparing the 30 mm flying bumblebee bat and the 30 metre-long aquatic blue whale both mammals.

But the work now published shows that the variations in the blood system - necessary to adapt to the evolutionary changes found within the mammals’ world -can be explained quantitatively (for example by producing more cells or having the cells dividing faster), and are directly correlated to the animals’ body mass and do not require any fundamental alteration in the haematopoietic process.

Why do humans cooperate in things as diverse as environment conservation or the creation of fairer societies, even when they don’t receive anything in exchange or, worst, they might even be penalized? This is a question that has puzzled academics for centuries, especially since in evolution the basis for the “survival of the fittest” is, after all, selfishness.
But in an article just published in the journal Nature, three Portuguese theoretical physicists developed a mathematical model capable of providing a way out from this conundrum through the introduction of social diversity - a ubiquitous characteristic of modern social networks - and suggesting that that the act of cooperation may depend on one’s social context/ranking. And in fact, when social diversity was taken into account the numbers of those cooperating increased in direct relation to the system diversity.

Scientists in Portugal just found a new molecular mechanism behind colorectal cancer in which a mutated and a normal, but over-expressed, gene cooperate and are both needed to create the disease. The research, published in the journal Gastroenteroloy1, also reveals how a technique called RNA interference can – by inactivating both genes - kill, in just 48 hours, as much as 80% of cancer cells. These are extremely promising results if transferred into new therapies for humans against a disease, which is still one of the most common cancers in the western world.
Colorectal cancer affects the colon, rectum and appendix and is not only the third most common form of cancer, but also the second cancer-related cause of death in the Western world, according to the World Health Organization. The disease kills about 655,000 people per year worldwide, with 16,000 only in the UK, even if it has a high cure rate if early detected and treated.

Machado Joseph disease (MJD) is a neurodegenerative disorder associated with deposits of an aberrant form of the protein ataxin-3 in the brain. The disease is also fatal and the most common hereditary motor neurodegenerative disease in many countries. Despite this, not much is known about MJD including the neurological basis of some of its symptoms, which cannot be linked to the brain damage found in patients.
But now, researchers in Portugal and France using a new animal model of the disease were able to show, for the first time, that MJD also affects the striatum, a brain area associated with movement and balance control.
These new findings, just published as advance online publication in the journal Human Molecular Genetics, finally clarify the cause of previously unexplained symptoms, such as muscle twisting and abrupt dance-like movements of the limbs. The research helps to understand better a still incurable pathology while also providing a new animal model to study the disease as well as potential treatments.

A gene called Diaphanous (or Dia) has just been uncovered as a major regulator during embryo formation. The research now published in the journal Development shows how Dia mutations in fruit flies embryos result in a serious of defects during morphogenesis (process by which cells differentiate into tissues and structures), including loss of adhesion, abnormal movements and even migration of cells from one tissue to another.
The discovery contributes to a better understanding of how tissue and organ formation is regulated and, consequently, to, one day, be able to intervene therapeutically. Furthermore, the loss of adhesion and abnormal mobility that occurs when Dia is mutated is very similar to what happens during cancer metastases formation, suggesting that this gene might also have a role in cancer.

Alzheimer's disease (AD) affects as much as 10% of the world population above 65 years of age but after years of research it is still not understood exactly how the disease appears and, even less, how to treat it.

But work just published in The EMBO Journal opens the door to new ways for disease intervention by showing that lipids found throughout the brain can dissolve the large insoluble protein plaques characteristic of the disease, releasing their soluble protofibrillar components, and also that it is the soluble components and not the insoluble plaques that provoke neural death.