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Berkeley, CA, United States

The Lawrence Berkeley National Laboratory , also known as the "Berkeley Lab", is a United States national laboratory located in the Berkeley Hills near Berkeley, California that conducts unclassified scientific research on behalf of the United States Department of Energy . It is managed and operated by the University of California, whose oldest campus, the University of California, Berkeley's main campus, it overlooks. Plans announced by the university in 2012 called for a second Berkeley Lab campus to be built on land it owns nearby at Richmond Field Station. Wikipedia.

Mills E.,Lawrence Berkeley National Laboratory
Science | Year: 2012

Insurance industry trends show how market-based mechanisms support climate change mitigation and adaptation. Source

Blow M.J.,Lawrence Berkeley National Laboratory
Nature genetics | Year: 2010

Accurate control of tissue-specific gene expression plays a pivotal role in heart development, but few cardiac transcriptional enhancers have thus far been identified. Extreme noncoding-sequence conservation has successfully predicted enhancers that are active in many tissues but has failed to identify substantial numbers of heart-specific enhancers. Here, we used ChIP-Seq with the enhancer-associated protein p300 from mouse embryonic day 11.5 heart tissue to identify over 3,000 candidate heart enhancers genome wide. Compared to enhancers active in other tissues we studied at this time point, most candidate heart enhancers were less deeply conserved in vertebrate evolution. Nevertheless, transgenic mouse assays of 130 candidate regions revealed that most function reproducibly as enhancers active in the heart, irrespective of their degree of evolutionary constraint. These results provide evidence for a large population of poorly conserved heart enhancers and suggest that the evolutionary conservation of embryonic enhancers can vary depending on tissue type. Source

Ritchie R.O.,Lawrence Berkeley National Laboratory
Nature Materials | Year: 2011

The attainment of both strength and toughness is a vital requirement for most structural materials; unfortunately these properties are generally mutually exclusive. Although the quest continues for stronger and harder materials, these have little to no use as bulk structural materials without appropriate fracture resistance. It is the lower-strength, and hence higher-toughness, materials that find use for most safety-critical applications where premature or, worse still, catastrophic fracture is unacceptable. For these reasons, the development of strong and tough (damage-tolerant) materials has traditionally been an exercise in compromise between hardness versus ductility. Drawing examples from metallic glasses, natural and biological materials, and structural and biomimetic ceramics, we examine some of the newer strategies in dealing with this conflict. Specifically, we focus on the interplay between the mechanisms that individually contribute to strength and toughness, noting that these phenomena can originate from very different lengthscales in a material's structural architecture. We show how these new and natural materials can defeat the conflict of strength versus toughness and achieve unprecedented levels of damage tolerance within their respective material classes. © 2011 Macmillan Publishers Limited. All rights reserved. Source

Phillips C.M.,Lawrence Berkeley National Laboratory
ACS chemical biology | Year: 2011

The high cost of enzymes for saccharification of lignocellulosic biomass is a major barrier to the production of second generation biofuels. Using a combination of genetic and biochemical techniques, we report that filamentous fungi use oxidative enzymes to cleave glycosidic bonds in cellulose. Deletion of cdh-1, the gene encoding the major cellobiose dehydrogenase of Neurospora crassa, reduced cellulase activity substantially, and addition of purified cellobiose dehydrogenases from M. thermophila to the Δcdh-1 strain resulted in a 1.6- to 2.0-fold stimulation in cellulase activity. Addition of cellobiose dehydrogenase to a mixture of purified cellulases showed no stimulatory effect. We show that cellobiose dehydrogenase enhances cellulose degradation by coupling the oxidation of cellobiose to the reductive activation of copper-dependent polysaccharide monooxygenases (PMOs) that catalyze the insertion of oxygen into C-H bonds adjacent to the glycosidic linkage. Three of these PMOs were characterized and shown to have different regiospecifities resulting in oxidized products modified at either the reducing or nonreducing end of a glucan chain. In contrast to previous models where oxidative enzymes were thought to produce reactive oxygen species that randomly attacked the substrate, the data here support a direct, enzyme-catalyzed oxidation of cellulose. Cellobiose dehydrogenases and proteins related to the polysaccharide monooxygenases described here are found throughout both ascomycete and basidiomycete fungi, suggesting that this model for oxidative cellulose degradation may be widespread throughout the fungal kingdom. When added to mixtures of cellulases, these proteins enhance cellulose saccharification, suggesting that they could be used to reduce the cost of biofuel production. Source

Biggin M.,Lawrence Berkeley National Laboratory
Developmental Cell | Year: 2011

To understand how transcription factors function, it is essential to determine the range of genes that they each bind and regulate in vivo. Here I review evidence that most animal transcription factors each bind to a majority of genes over a quantitative series of DNA occupancy levels. These continua span functional, quasifunctional, and nonfunctional DNA binding events. Factor regulatory specificities are distinguished by quantitative differences in DNA occupancy patterns. I contrast these results with models for transcription networks that define discrete sets of direct target and nontarget genes and consequently do not fully capture the complexity observed in vivo. © 2011 Elsevier Inc. Source

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