Wednesday, July 25, 2012

XENON100 announced the new results from 225 days data

The XENON100 collaboration submitted a paper with the new results of a 225 days to PRL, excluding previously unexplored parameter space and questioning the light WIMP interpretation of the DAMA and CoGeNT results.

The preprint can be found here:

Friday, July 20, 2012

Emerging roles of non-coding RNAs in brain evolution, development, plasticity and disease

Novel classes of small and long non-coding RNAs (ncRNAs) are being characterized at a rapid pace, driven by recent paradigm shifts in our understanding of genomic architecture, regulation and transcriptional output, as well as by innovations in sequencing technologies and computational and systems biology. These ncRNAs can interact with DNA, RNA and protein molecules; engage in diverse structural, functional and regulatory activities; and have roles in nuclear organization and transcriptional, post-transcriptional and epigenetic processes. This expanding inventory of ncRNAs is implicated in mediating a broad spectrum of processes including brain evolution, development, synaptic plasticity and disease pathogenesis.

Thursday, July 12, 2012

The Attention System of the Human Brain: 20 Years After

Here, the author update their 1990 Annual Review of Neuroscience article, “The Attention System of the Human Brain.” The framework presented in the original article has helped to integrate behavioral, systems, cellular, and molecular approaches to common problems in attention research. Research on orienting and executive functions has supported the addition of new networks of brain regions. Developmental studies have shown important changes in control systems between infancy and childhood. In some cases, evidence has supported the role of specific genetic variations, often in conjunction with experience, that account for some of the individual differences in the efficiency of attentional networks. The findings have led to increased understanding of aspects of pathology and to some new interventions.

Steven E. Petersen and Michael I. Posner
The Attention System of the Human Brain: 20 Years AfterAnnual Review of Neuroscience
Vol. 35: 73-89 (Volume publication date July 2012)
First published online as a Review in Advance on April 12, 2012
DOI: 10.1146/annurev-neuro-062111-150525

Friday, July 6, 2012

piRNAs Can Trigger a Multigenerational Epigenetic Memory in the Germline of C. elegans

Transgenerational effects have wide-ranging implications for human health, biological adaptation, and evolution; however, their mechanisms and biology remain poorly understood. Here, we demonstrate that a germline nuclear small RNA/chromatin pathway can maintain stable inheritance for many generations when triggered by a piRNA-dependent foreign RNA response in C. elegans. Using forward genetic screens and candidate approaches, we find that a core set of nuclear RNAi and chromatin factors is required for multigenerational inheritance of environmental RNAi and piRNA silencing. These include a germline-specific nuclear Argonaute HRDE1/WAGO-9, a HP1 ortholog HPL-2, and two putative histone methyltransferases, SET-25 and SET-32. piRNAs can trigger highly stable long-term silencing lasting at least 20 generations. Once established, this long-term memory becomes independent of the piRNA trigger but remains dependent on the nuclear RNAi/chromatin pathway. Our data present a multigenerational epigenetic inheritance mechanism induced by piRNAs.

Alyson Ashe et al.
Cell. 2012 July 6; 150(1): 88–99.
doi: 10.1016/j.cell.2012.06.018

Thursday, July 5, 2012

Higgs Particle has been discovered by LHC!

Finally the Higgs Particle has been discovered by LHC!
Here is the Higgs -> two gamma decay, observed by CMS.
The paper is available

Sunday, July 1, 2012

Early Events in Axon/Dendrite Polarization

Differentiation of axons and dendrites is a critical step in neuronal development. Here we review the evidence that axon/dendrite formation during neuronal polarization depends on the intrinsic cytoplasmic asymmetry inherited by the postmitotic neuron, the exposure of the neuron to extracellular chemical factors, and the action of anisotropic mechanical forces imposed by the environment. To better delineate the functions of early signals among a myriad of cellular components that were shown to influence axon/dendrite formation, the authors discuss their functions by distinguishing their roles as determinants, mediators, or modulators and consider selective degradation of these components as a potential mechanism for axon/dendrite polarization. Finally, we examine whether these early events of axon/dendrite formation involve local autocatalytic activation and long-range inhibition, as postulated by Alan Turing for the morphogenesis of patterned biological structure.

Pei-lin Cheng and Mu-ming Poo
Annual Review of Neuroscience
Vol. 35: 181-201 (Volume publication date July 2012)
DOI: 10.1146/annurev-neuro-061010-113618

Evolution of Synapse Complexity and Diversity

Proteomic studies of the composition of mammalian synapses have revealed a high degree of complexity. The postsynaptic and presynaptic terminals are molecular systems with highly organized protein networks producing emergent physiological and behavioral properties. The major classes of synapse proteins and their respective functions in intercellular communication and adaptive responses evolved in prokaryotes and eukaryotes prior to the origins of neurons in metazoa. In eukaryotes, the organization of individual proteins into multiprotein complexes comprising scaffold proteins, receptors, and signaling enzymes formed the precursor to the core adaptive machinery of the metazoan postsynaptic terminal. Multiplicative increases in the complexity of this protosynapse machinery secondary to genome duplications drove synaptic, neuronal, and behavioral novelty in vertebrates. Natural selection has constrained diversification in mammalian postsynaptic mechanisms and the repertoire of adaptive and innate behaviors. The evolution and organization of synapse proteomes underlie the origins and complexity of nervous systems and behavior.

Richard D. Emes1 and Seth G.N. Grant2
Annual Review of Neuroscience
Vol. 35: 111-131 (Volume publication date July 2012)
DOI: 10.1146/annurev-neuro-062111-150433