Aquatic biodiversity assessment for the lazy

The world is covered in DNA. In any ecosystem, extracellular DNA fragments can be found that once formed the genomes of a variety of micro‐ and macroorganisms. A few years ago, it was proposed to use this environmental DNA (eDNA) as a source of information on local vertebrate biodiversity (Ficetola et al. 2008 ; Taberlet et al. 2012 ). This idea offered an elegant solution to take up the gauntlet of rapidly increasing monitoring needs. Coupled with barcoding efforts, it promised to be cost‐efficient in many respects, for example man‐hours and taxonomic expertise. Ecologists and conservation biologists with an interest in aquatic ecosystems have enthusiastically adopted and pioneered this new method, producing dozens of eDNA studies. Most of these studies have, however, focused on a single or a few aquatic species. In this issue of Molecular Ecology, Valentini et al. ( 2016 ) move the field a step further by demonstrating that metabarcoding approaches – which simultaneously target large groups of organisms such as amphibians or fish – can match and sometimes even outperform other inventory methods.     

PAT： waking up a lazy sleeping beauty

Once upon a time, there was an unusual corn; and unlike its normal siblings, its stalk grew towards the ground rather than in an upward direction. The sleeping stature of the corn was portrayed in early 1930s as ＂lazy＂ by Jenkins and Gerhardt. Later, lazy appeared to be a fashion in the plant kingdom, found in rice, barley, tomato and several other species . These seemingly magic spellchanted plants have drawn considerable interests of plant biologists and breeders for many decades. To breeders, the lazy phenotype, viewed as tillering or branching angles of stems （or termed as culms in crop plants）, represents a key characteristic important for controlling photosynthesis efficiency and planting density, and thus a crucial factor in determining crop production .     

Social evolution: lazy wasps look to the future

Female hairy-faced hover wasps forage for the young of a dominant breeder, but some forage more than others. New research shows that helpers decide how much to help by looking to the future.     

The "lazy" NK cells of Chediak-Higashi syndrome

Natural killer (NK) function, measured in a short-term (4-hr) 51Cr-release assay, is profoundly depressed in circulating PBL of donors with Chediak-Higashi syndrome (CHS). In this study, we demonstrate that CHS NK cells can express relatively normal lytic function after prolonged exposure in vitro to high levels of activating as well as cytotoxic stimuli. After activation with the human cloned interferon (B1) for 24 hr, CHS NK cells have lytic activity comparable to unactivated normals in a 4-hr 51Cr-release assay. In addition, after 5 days of activation with mitomycin C-treated B cell lines, CHS NK cells have levels of activity similar to those of activated normals but are defective in generating cytotoxic cells capable of lysing the stimulator B cell. Even though CHS NK cells are defective in a 4-hr 51Cr-release assay, after 16 hr they enhance their killing capability 200 to 400-fold. In fact, after 16 hr of interaction with K562 target cells, CHS NK cells are capable of releasing NK soluble cytotoxic factors. These results are consistent with the hypothesis that CHS NK cells have all the necessary cellular structures and molecules required for them to function as lytic effector cells, but their lack of cytotoxic function is due to a relative refractoriness in initiating the post-binding lytic mechanism.     

Mitosis: Don't get mad, get even

The ‘mitotic spindle checkpoint’ ensures that, before a cell exits from mitosis, all of its chromosomes are aligned on the spindle to form the metaphase plate. Mad2 is an essential component of this checkpoint system and it binds specifically to unattached kinetochores.     

Learning to get along despite struggling to get by

How cooperation can evolve by natural selection is important for understanding the evolutionary transition from unicellular to multicellular life. Here we review the evolutionary theories for cooperation, with emphasis on the mechanisms that can favor cooperation and reduce conflict in multicellular organisms.     

Cool hamsters get sleepy

The relationship between sleep and natural hypothermic states, like daily torpor and hibernation, has always been of interest for sleep researchers. The three states were long considered functionally homologous. However, while investigating the effects of daily torpor on sleep in the Djungarian hamster (Phodopus sungorus), the results suggested that the animals are sleep deprived during hypothermia, and can only recover this sleep debt after return to euthermia. The data indicate that an important function of sleep cannot be fulfilled during the torpid state, a finding which may give additional insights into the processes involved in sleep regulation.