Week in Review: January 20–24

Mistimed sleep disrupts human transcriptome; canine tumor genome; de novo Drosophila genes; UVA light lowers blood pressure; aquatic microfauna fight frog-killing fungus

The 28-hour sleep/wake transcriptome

FLICKR, JULIE VACCALLUZZOA mistimed sleep cycle drastically reduces the number of genes that are expressed in a 24-hour rhythm, scientists reported in PNAS this week (January 20). Most of those genes are involved in transcription and translation, the authors noted.

“The shifting the time of sleep has enormous consequences,” said neurobehavioral geneticist Valter Tucci at the Italian Institute of Technology in Genova, who was not involved in the study. “It’s not by chance that evolution has favored the development of sleep at a particular time,” he added.

Transmissible dog cancer genome

WIKIPEDIA, SCMWResearchers reported genome sequences for two canine transmissible venereal tumors in Science this week (January 23), noting that the cancer has picked up around 1.9 million mutations over the last 11,000 or so years. The University of Sydney’s Katherine Belov, who was not involved in the work, pointed out similarities between this transmissible dog cancer and devil facial tumor disease, which continues to ravage Tasmanian devil populations.

“I think it is really important that we continue to study these contagious cancers,” Belov told The Scientist. “They have evolved at least twice. What allows these cancers to emerge, and to become successful and immortal? If we can answer these questions, we will gain insights into human cancers too.”

De novo genes in Drosophila

WIKIMEDIA, MUHAMMAD MAHDI KARIMScanning the transcriptomes of several Drosophila strains, researchers uncovered dozens of possible de novo genes in each. Presented in Sciencethis week (January 23), the research supports the notion that de novo gene formation may even be a common phenomenon.

“Until recently, de novo origin of genes was considered to be so unlikely as to be impossible,” comparative genomicist Aoife McLysaght from Trinity College in Dublin, Ireland, who was not involved in the study, told The Scientist.

Light releases skin NO stores

FLICKR, ROSMARYUVA light exposure releases nitric oxide (NO) metabolites from storage in human skin, which through their vasodilative effects reduce blood pressure, scientists showed in the Journal of Investigative Dermatology this week (January 20). The team now aims to investigate the source of these subcutaneous NO stores as well as the dynamics of the photolytic release of metabolites nitrite and nitrate.

“From a mechanistic angle, it’s important to understand what contributes to determining the concentration of this storage material in the skin, and whether there is anything [else] that would facilitate translocation from the skin to the circulation,” said University of Southampton’s Martin Feelisch, who led the study. “It’s a complete black box at the moment.”

Fighting frog-killing fungus

ISABELLA OLESKYInvestigating why chytridiomycosis affected some amphibian populations more than others residing in nearby lakes, researchers found evidence that aquatic microscopic fauna—such as Daphnia, Paramecium, and rotifers—can consume free-floating zoospores from the fungal pathogen underlying the deadly disease, Batrachochytrium dendrobatidis (Bd), preventing it from infecting as many frogs. Two separate teams reported related findings inEcology and Evolution and Current Biology last year (September and December 2013).