Necroptosis, a Potential Therapeutic Target for Neurological Disorders

Necrosis is considered to be an unregulated and chaotic cell death. However, recent advances in cell death strategies support necroptosis as a form of regulated programmed necrotic cell death. In response to TNF-a or Fas ligands, necroptosis can be induced by cell death receptors in multiple cell lines in the presence of a caspase inhibitor z-VAD; necroptotic cell death has been found to play an important role in normal development, immunity, inflammation, cancer, and human diseases. In this chapter, the molecular mechanisms governing necroptosis, recent findings about the upstream and downstream schema of necroptosis, and potential therapeutic targets in neurological disorders are discussed. After being activated by TNF-a (or Fas ligands) and death receptors, receptor-interacting proteins 1 and 3 (RIP1 and RIP3) form a complex, which play a central role in the induction of necroptosis. RIP3 phosphorylates and activates mitochondrial proteins mixed lineage kinase domain-like protein (MLKL) and PGAM5, resulting in the execution of necroptosis by dynamin-related protein 1, the GTPase that controls mitochondrial fission. Some small molecules such as necrostain-1 and necrosulfonamide target different steps of necroptosis and impede the progress of necroptosis. FADD, caspase-8, CLIP, and CYLD positively or negatively regulate RIP1-/RIP3-dependent necroptosis by different mechanisms. Recent studies demonstrate the involvement of necroptosis in many neurological disorders including stroke, trauma, neonatal hypoxic-ischemic encephalopathy, and Huntington\u27s disease. As a potential therapeutic target, the understanding of necroptotic mechanisms will provide new insights to develop more potent neuroprotectants and specific therapeutic strategies for clinical treatments of neurological disorders

An integrated map of genetic variation from 1,092 human genomes

By characterizing the geographic and functional spectrum of human genetic variation, the 1000 Genomes Project aims to build a resource to help to understand the genetic contribution to disease. Here we describe the genomes of 1,092 individuals from 14 populations, constructed using a combination of low-coverage whole-genome and exome sequencing. By developing methods to integrate information across several algorithms and diverse data sources, we provide a validated haplotype map of 38 million single nucleotide polymorphisms, 1.4 million short insertions and deletions, and more than 14,000 larger deletions. We show that individuals from different populations carry different profiles of rare and common variants, and that low-frequency variants show substantial geographic differentiation, which is further increased by the action of purifying selection. We show that evolutionary conservation and coding consequence are key determinants of the strength of purifying selection, that rare-variant load varies substantially across biological pathways, and that each individual contains hundreds of rare non-coding variants at conserved sites, such as motif-disrupting changes in transcription-factor-binding sites. This resource, which captures up to 98% of accessible single nucleotide polymorphisms at a frequency of 1% in related populations, enables analysis of common and low-frequency variants in individuals from diverse, including admixed, populations

Guidelines for the use and interpretation of assays for monitoring autophagy.

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field