Newly launched nerve cells in a growing embryo must chart their course to distant destinations, and many of the means they use to navigate have yet to surface. In a study published in the current issue of the journal Neuron, scientists at the Salk Institute for Biological Studies have recovered a key signal that guides motor neurons – the nascent cells that extend from the spinal cord and must find their way down the length of limbs such as arms, wings and legs.

The Salk study, led by Samuel Pfaff, Ph.D, a professor in the Gene Expression Laboratory, identifies a mutation they christened Magellan, after the Portuguese mariner whose ship Victoria was first to circumnavigate the globe.

Writing in Atoms for Peace, Energy consultant David Wood suggests that Iran's demands for nuclear power in economic and technical terms are a justified response to rapid growth in domestic energy demands and an increased dependence on oil exports for revenue.

Despite its vast oil and gas reserves, years of under-investment in Iran has limited access to technology and stifled its production capacity. Indeed, Iran now relies on imports for certain refined petroleum products and natural gas. Wood argues that the development of this situation has forced Iran to consider alternative future energy solutions.

An essential component of the human immunodeficiency virus (HIV-1) molecular machinery responsible for infecting cells consists of functionally-specialized layers, according to a study by investigators at the University of California San Diego (UCSD) Antiviral Research Center (AVRC), published November 23 in PLoS Computational Biology.

The unprecedented genetic diversity and adaptability of HIV-1 has so far foiled the best efforts to eradicate the global HIV/AIDS epidemic. The surface of the HIV-1 particle is studded with protein spikes that allow the virus to enter human cells. This study examined an important component of the protein spike called the third variable loop (labeled “V3”).

There has recently been a huge growth in transnational English language television channels, with the launch in the UK of Al Jazeera English, Press TV (Iran), CCTV9 (China), France 24 and Russia Today. These join existing channels such as CNN International, Voice of America and BBC World TV. But what are the purposes of these channels? Who are they for and who is watching them? Do they constitute a global group of English speaking nations, an ‘Anglosphere’?

These were some of the questions debated by media professionals and academics at a workshop, sponsored by the Economic and Social Research Council (ESRC), entitled ‘Transnational TV News and Media Diplomacy: Al Jazeera English in Context.’

Researchers writing in BMC Genomics reveal that the grapevine's gene expression analysis reveals two distinct molecular and functional phases that correspond with the green and red grape stages.

Researchers have reported the first biochemical evidence that reactive oxygen species accumulate during the color transition. Stefania Pilati and fellow researchers from the IASMA Research Center, San Michele all'Adige, Italy, investigated ripening Pinot Noir grapes (Vitis vinifera L.) to identify fruit ripening genes and investigate seasonal influences.

They found a core set of more than 1,400 ripening-specific genes that fluctuated similarly across three growing seasons and a smaller gene group strongly influenced by climatic conditions.

An enormous submarine landslide that disintegrated 60,000 years ago produced the longest flow of sand and mud yet documented on Earth. The massive submarine flow travelled 1,500 kilometres – the distance from London to Rome – before depositing its load.

Details of the landslide and consequent sediment flow are reported online today in Nature by Dr Peter Talling from the University of Bristol, with colleagues from the National Oceanography Centre in Southampton and several other institutions.

Dr Talling said: “The volume of sediment transported by this flow in the deep ocean is difficult to comprehend. It was one of the largest movements of material ever to occur on our planet. This mass was ten times that transported to the ocean every year by all of the Earth’s rivers.