The rockefeller university

SPOAN syndrome is a neurodegenerative disorder mainly characterized by spastic paraplegia, optic atrophy and neuropathy (SPOAN). Affected patients are wheelchair bound after 15 years old, with progressive joint contractures and spine deformities. SPOAN patients also have sub normal vision secondary to apparently non-progressive congenital optic atrophy. A potential causative gene was mapped at 11q13 ten years ago. Here we performed next-generation sequencing in SPOAN-derived samples. While whole-exome sequencing failed to identify the causative mutation, whole-genome sequencing allowed to detect a homozygous 216-bp deletion (chr11. hg19:g. 66,024,557_66,024,773del) located at the non-coding upstream region of the KLC2 gene. Expression assays performed with patient's fibroblasts and motor neurons derived from SPOAN patients showed KLC2 overexpression. Luciferase assay in constructs with 216-bp deletion confirmed the overexpression of gene reporter, varying from 48 to 74%, as compared with wild-type. Knockdown and overexpression of klc2 in Danio rerio revealed mild to severe curly-tail phenotype, which is suggestive of a neuromuscular disorder. Overexpression of a gene caused by a small deletion in the non-coding region is a novel mechanism, which to the best of our knowledge, was never reported before in a recessive condition. Although the molecular mechanism of KLC2 up-regulation still remains to be uncovered, such example adds to the importance of non-coding regions in human pathology.

Ingestion of a high-fat diet composed mainly of the saturated fatty acid, palmitic (PA), and the unsaturated fatty acid, oleic (OA), stimulates transcription in the brain of the opioid neuropeptide, enkephalin (ENK), which promotes intake of substances of abuse. To understand possible underlying mechanisms, this study examined the nuclear receptors, peroxisome proliferator-activated receptors (PPARs), and tested in hypothalamic and forebrain neurons from rat embryos whether PPARs regulate endogenous ENK and the fatty acids themselves affect these PPARs and ENK. The first set of experiments demonstrated that knocking down PPAR delta, but not PPAR alpha or PPAR gamma, increased ENK transcription, activation of PPAR6 by an agonist decreased ENK levels, and PPAR delta neurons coexpressed ENK, suggesting that PPAR6 negatively regulates ENK. In the second set of experiments, PA treatment of hypothalamic and forebrain neurons had no effect on PPAR6 protein while stimulating ENK mRNA and protein, whereas OA increased both mRNA and protein levels of PPAR6 in forebrain neurons while having no effect on ENK mRNA and increasing ENK levels. These findings show that PA has a strong, stimulatory effect on ENK and weak effect on PPAR6 protein, whereas OA has a strong stimulatory effect on PPAR6 and weak effect on ENK, consistent with the inhibitory effect of PPAR6 on ENK. They suggest a function for PPAR delta, perhaps protective in nature, in embryonic neurons exposed to fatty acids from a fat-rich diet and provide evidence for a mechanism contributing to differential effects of saturated and monounsaturated fatty acids on neurochemical systems involved in consummatory behavior.

Environmental enrichment has multiple effects on behaviour, including modification of responses to psychostimulant drugs mediated by striatal neurons. However, the underlying molecular and cellular mechanisms are not known. Here we show that DARPP-32, a hub signalling protein in striatal neurons, interacts with adducins, which are cytoskeletal proteins that cap actin filaments' fast-growing ends and regulate synaptic stability. DARPP-32 binds to adducin MARCKS domain and this interaction is modulated by DARPP-32 Ser97 phosphorylation. Phospho-Thr75-DARPP-32 facilitates beta-adducin Ser713 phosphorylation through inhibition of a cAMP-dependent protein kinase/phosphatase-2A cascade. Caffeine or 24-h exposure to a novel enriched environment increases adducin phosphorylation in WT, but not T75A mutant mice. This cascade is implicated in the effects of brief exposure to novel enriched environment on dendritic spines in nucleus accumbens and cocaine locomotor response. Our results suggest a molecular pathway by which environmental changes may rapidly alter responsiveness of striatal neurons involved in the reward system.

The key problem in human infectious diseases was posed at the turn of the 20th century: their pathogenesis. For almost any given virus, bacterium, fungus, or parasite, life-threatening clinical disease develops in only a small minority of infected individuals. Solving this infection enigma is important clinically, for diagnosis, prognosis, prevention, and treatment. Some microbes will inevitably remain refractory to, or escape vaccination, or chemotherapy, or both. The solution also is important biologically, because the emergence and evolution of eukaryotes alongside more rapidly evolving prokaryotes, archaea, and viruses posed immunological challenges of an ecological and evolutionary nature. We need to study these challenges in natural, as opposed to experimental, conditions, and also at the molecular and cellular levels. According to the human genetic theory of infectious diseases, inborn variants underlie life-threatening infectious diseases. Here I review the history of the field of human genetics of infectious diseases from the turn of the 19th century to the second half of the 20th century. This paper thus sets the scene, providing the background information required to understand and appreciate the more recently described monogenic forms of resistance or predisposition to specific infections discussed in a second paper in this issue.

Clinical and animal studies indicate that maternal consumption of ethanol during pregnancy increases alcohol drinking in the offspring. Possible underlying mechanisms may involve orexigenic peptides, which are stimulated by prenatal ethanol exposure and themselves promote drinking. Building on evidence that ethanol stimulates neuroimmune factors such as the chemokine CCL2 that in adult rats is shown to colocalize with the orexigenic peptide, melanin-concentrating hormone (MCH) in the lateral hypothalamus (LH), the present study sought to investigate the possibility that CCL2 or its receptor CCR2 in LH is stimulated by prenatal ethanol exposure, perhaps specifically within MCH neurons. Our paradigm of intraoral administration of ethanol to pregnant rats, at low-to-moderate doses (1 or 3 g/kg/day) during peak hypothalamic neurogenesis, caused in adolescent male offspring twofold increase in drinking of and preference for ethanol and reinstatement of ethanol drinking in a two-bottle choice paradigm under an intermittent access schedule. This effect of prenatal ethanol exposure was associated with an increased expression of MCH and density of MCH+ neurons in LH of preadolescent offspring. Whereas CCL2(+) cells at this age were low in density and unaffected by ethanol, CCR2(+) cells were dense in LH and increased by prenatal ethanol, with a large percentage (83-87%) identified as neurons and found to colocalize MCH. Prenatal ethanol also stimulated the genesis of CCR2(+) and MCH+ neurons in the embryo, which co-labeled the proliferation marker, BrdU. Ethanol also increased the genesis and density of neurons that co-expressed CCR2 and MCH in LH, with triple-labeled CCR2(+)/MCH+/BrdU(+) neurons that were absent in control rats accounting for 35% of newly generated neurons in ethanol-exposed rats. With both the chemokine and MCH systems believed to promote ethanol consumption, this greater density of CCR2(+)/MCH+ neurons in the LH of preadolescent rats suggests that these systems function together in promoting alcohol drinking during adolescence. (C) 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Background There is a presumption that, for patients with uncontrolled blood pressure (BP), early follow-up, that is, within 4 weeks of an elevated reading, improves BP control. However, data are lacking regarding effective interventions for increasing clinician frequency of follow-up visits and whether such interventions improve BP control. Methods/design Blood Pressure Visit Intensification Study in Treatment involves a multimodal approach to improving intensity of follow-up in 12 community health centers using a stepped wedge study design. Discussion The study will inform effective interventions for increasing frequency of follow-up visits among patients with uncontrolled BP and determine whether increasing follow-up frequency is associated with better BP control.

Telomere crisis occurs during tumorigenesis when depletion of the telomere reserve leads to frequent telomere fusions. The resulting dicentric chromosomes have been proposed to drive genome instability. Here, we examine the fate of dicentric human chromosomes in telomere crisis. We observed that dicentric chromosomes invariably persisted through mitosis and developed into 50-200 mm chromatin bridges connecting the daughter cells. Before their resolution at 3-20 hr after anaphase, the chromatin bridges induced nuclear envelope rupture in interphase, accumulated the cytoplasmic 30 nuclease TREX1, and developed RPA-coated single stranded (ss) DNA. CRISPR knockouts showed that TREX1 contributed to the generation of the ssDNA and the resolution of the chromatin bridges. Post-crisis clones showed chromothripsis and kataegis, presumably resulting from DNA repair and APOBEC editing of the fragmented chromatin bridge DNA. We propose that chromothripsis in human cancer may arise through TREX1-mediated fragmentation of dicentric chromosomes formed in telomere crisis.

This year we celebrate Blood's 70th year of publication. Created from the partnership of the book publisher Henry M. Stratton and the prominent hematologist Dr William Dameshek of Tufts School of Medicine, Blood has published many papers describing major advances in the science and clinical practice of hematology. Blood's founding antedated that of the American Society of Hematology (ASH) by more than 11 years and Stratton and Dameshek helped galvanize support for the creation of ASH. In this review, I place the birth of Blood in the context of the history of hematology before 1946, emphasizing the American experience from which it emerged, and focusing on research conducted during World War II. I also provide a few milestones along Blood's 70 years of publication, including: the growth in Blood's publications, the evolution of its appearance, the countries of submission of Blood papers, current subscriptions to Blood, and the evolution of topics reported in Blood's papers. The latter provides a snapshot of the evolution of hematology as a scientific and clinical discipline and the introduction of new technology to study blood and bone marrow. Detailed descriptions of the landmark discoveries reported in Blood will appear in later papers celebrating Blood's birthday authored by past Editors-in-Chief.

At the eukaryotic DNA replication fork, it is widely believed that the Cdc45-Mcm2-7-GINS (CMG) helicase is positioned in front to unwind DNA and that DNA polymerases trail behind the helicase. Here we used single-particle EM to directly image a Saccharomyces cerevisiae replisome. Contrary to expectations, the leading strand Pol epsilon is positioned ahead of CMG helicase, whereas Ctf4 and the lagging-strand polymerase (Pol) alpha-primase are behind the helicase. This unexpected architecture indicates that the leading-strand DNA travels a long distance before reaching Pol epsilon, first threading through the Mcm2-7 ring and then making a U-turn at the bottom and reaching Pol a at the top of CMG. Our work reveals an unexpected configuration of the eukaryotic replisome, suggests possible reasons for this architecture and provides a basis for further structural and biochemical replisome studies.

Background: Oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) isolates have been increasingly reported worldwide, but data regarding the African continent have not been available. Methods: Between 2010 and 2014, 1462 inpatients and healthcare workers were screened for MRSA nasal carriage in Sao Tome and Principe (STP) and Angola, two Portuguese-speaking African countries (PALOP countries). We determined the presence of the mecA gene and the antimicrobial susceptibility profiles of the isolates. OS-MRSA clonal lineages were identified as well as the presence of virulence determinants, including Panton-Valentine leucocidin (PVL). Results: Out of 164 S. aureus hospital isolates tested, 29 (17.7%) were mecA positive, but susceptible to oxacillin, showing oxacillin MICs <= 3 mg/L. All OS-MRSA isolates were resistant to cefoxitin and most of them were also resistant to at least two antimicrobials other than beta-lactams. The 29 OS-MRSA were distributed into two major clonal lineages: (i) PFGE type B-ST88-SCCmec IVa, associated with spa types t186/t325/t786/t1814/t1951, detected in Angola (n = 5) and STP (n = 10); and (ii) PFGE type C-t451/t648-ST8-SCCmec V, exclusively found in STP (n = 9). OS-MRSA showed at least two virulence determinants. PVL was detected in an isolate recovered in STP. Conclusions: We describe a high prevalence of OS-MRSA among S. aureus strains recovered in two African countries. OS-MRSA in PALOP countries were mainly associated with ST88 and ST8, two prevalent MRSA clonal types in these countries. If direct testing for mecA is not available, cefoxitin susceptibility testing is highly recommended to avoid the misidentification of OS-MRSA.