Open Reading Frame: Darwin’s new beetle, origami drug delivery & reproducibility research

Posted by Biome on 22nd February 2014 - 0 Comments


Open Reading Frame brings together a selection of recent publication highlights from elsewhere in the open access ecosystem. This week we take a look at the past few weeks in biology.

 

A birthday present for Charles Darwin
It is thought that only a tiny fraction of the world’s biodiversity has so far been classified by taxonomists, so adding a whole new genus to the global collection is always cause for celebration. This is doubly so if the specimens in question happened to be originally collected by Charles Darwin on his legendary voyage of the Beagle. Earlier this month, to coincide with Darwin’s 205th Birthday, a new genus of rove beetle from Argentina has been described, and named Darwinilus sedarisi in honour of its finder. The single beetle specimen was collected in 1832 from the Bahia Blanca region, and had languished in the vaults of London’s Natural History Museum before being serendipitously rediscovered in 2008, and reclassified on the basis of its highly unusual antennae – a major difference that had previously been overlooked when compared to other closely related species.
Chatzimanolis. ZooKeys

 

Reproducibility is dead, long live reproducibility
A number of scientific fields from psychology to environmental science have suffered recently from charges of irreproducibility, questioning whether they may truly be deemed scientific at all. In an ever-changing landscape of inquiry, in which different disciplines integrate to tackle new problems, maintaining a strict definition of what is and what is not science based on this measure may not be straightforward. In an effort to explore these boundaries, a new scheme is suggested by a group of Swiss and German researchers, termed ‘relation of relevance’ that takes into account the specific attributes of the system under study and distinguishes between different features by order of relevance. The authors claim that this new approach is a sound and empirical alternative to the current gold standard.
Atmanspacher et al. Royal Society Interface

 

New light shed on UV sensitivity in mammals
Among vertebrates, visual sensitivity to ultraviolet wavelengths is relatively common among reptiles, amphibians and birds, but much less is known about how widespread it is in mammals. Humans, like other primates, are insensitive to UV light, since the eye’s lens absorbs wavelengths below the ultraviolet threshold, preventing it from reaching the retina. However, whether the same applies to other mammalian species is not clear, as there has been a tendency in ocular research to be overlook less ‘glamorous’ species. Now, an analysis of lenses from 38 mammal species across 25 families reveals that UV sensitivity is far more widespread than previously thought, occurring in dogs, cats, and a range of other species. Difference in the specialization of the retina among samples also suggests that, in species insensitive to UV light, this is likely to have been lost in an evolutionary trade off favouring enhanced visual acuity.
Douglas & Jeffery. Proceedings of the Royal Society B

 

Plant pathogen expands its horizons
A major pathogen of sugarcane is a bacteria called Xanthomonas albilineans, the causative agent of a disease known as sugarcane leaf scald, which can cause death of the host plant. Once infected, plant leaves take on a burnt-like appearance as the pathogen infects xylem tissues. This targeting of infection to a single tissue type is thought to be characteristic of bacterial pathogens with small genomes sizes, although a new analysis of infected plants has highlighted that this picture may not be as straightforward as it seems. Using confocal microscopy to investigate infected plants in more details, researchers have now show that infection by this bacterium can also occur in vascular bundles, storage cells, and even in the extracellular spaces between cells. This is the first time that a pathogen normally associated with infection of vascular tissues had been recorded infecting non-vascular tissues, and raises questions about how specialized other similar plant pathogens may be to specific tissues.
Mensl et al. Open Biology

 

Origami aids targeted drug delivery
A new anti-cancer delivery system has been developed in which custom-made stretches of DNA are folded around molecules of a drug, before being released from a 2D nano-scale film in which they are embedded. This method of drug-trapping utilizes a technique known as DNA origami, which creates a highly-controlled way of housing specific drugs within a biologically-relevant structure, which can be later released at specifically controlled times, and under specified conditions. In this instance, researchers we able to create three different types of DNA origami nanostructure, which could be released from a nano-film composed of two-dimensional layers of DNA, when immersed in a substance called Fetal Bovine Serum. This mimics normal physiological conditions, changing electrostatic interactions within the nano-film, and leading to release of the drug-containing 3D origami structures once immersed.
Cho et al. Scientific Reports

 

Mechanisms of ‘male-killing’
The animal kingdom is full of parasites. One particularly sneaky microbe is from the genus Spiroplasma, which infects fruits flies and other insects. This bacterium lacks a cell wall, spending most of its time feasting off their host. Although they generally live a non-lethal parasitic lifestyle, they also have a darker side, killing developing male host embryos and thereby skewing the sex-ratio of a population. The precise mechanism underlying this host-killing behavior is not well understood, but a new analysis from researchers in Japan has shown that the parasite is able to hijack the machinery of the host involved in the control of cell death, causing developing male embryos to effectively commit suicide. They also find that neuronal defects seen in infected embryos are a result of a totally separate mechanism to that of cell death, suggesting a complex, multifaceted mechanism of male-killing.
Harumoto et al. PLoS Pathogens

 

Written by Simon Harold, Senior Executive Editor for the BMC Series.