Direct and indirect effects of light pollution on the performance of an herbivorous insect

Light pollution is a global disturbance with resounding impacts on a wide variety of organisms, but our understanding of these impacts is restricted to relatively few higher vertebrate species. We tested the direct effects of light pollution on herbivore performance as well as indirect effects mediated by host plant quality. We found that artificial light from streetlights alters plant toughness. Additionally, we found evidence of both direct and indirect effects of light pollution on the performance of an herbivorous insect, which indicates that streetlights can have cascading impacts on multiple trophic levels. Our novel findings suggest that light pollution can alter plant-insect interactions and thus may have important community-wide consequences.     

Deer do not affect short‐term rates of vegetation recovery in overwash fans on Fire Island after Hurricane Sandy

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Hepatocyte-Macrophage Acetoacetate Shuttle Protects against Tissue Fibrosis

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Complex Formation of RNA Silencing Proteins in the Perinuclear Region of Neurospora crassa

In Neurospora, genes not paired during meiosis are targeted by meiotic silencing by unpaired DNA (MSUD). Here, our bimolecular fluorescence complementation (BiFC) study suggests that RNA-directed RNA polymerase, Dicer, Argonaute, and others form a silencing complex in the perinuclear region, with intimate interactions among the majority of them. We have also shown that SAD-2 is likely the anchor for this assembly.     

In Silico Modeling-based Identification of Glucose Transporter 4 (GLUT4)-selective Inhibitors for Cancer Therapy

Tumor cells rely on elevated glucose consumption and metabolism for survival and proliferation. Glucose transporters mediating glucose entry are key proximal rate-limiting checkpoints. Unlike GLUT1 that is highly expressed in cancer and more ubiquitously expressed in normal tissues, GLUT4 exhibits more limited normal expression profiles. We have previously determined that insulin-responsive GLUT4 is constitutively localized on the plasma membrane of myeloma cells. Consequently, suppression of GLUT4 or inhibition of glucose transport with the HIV protease inhibitor ritonavir elicited growth arrest and/or apoptosis in multiple myeloma. GLUT4 inhibition also caused sensitization to metformin in multiple myeloma and chronic lymphocytic leukemia and a number of solid tumors suggesting the broader therapeutic utility of targeting GLUT4. This study sought to identify selective inhibitors of GLUT4 to develop a more potent cancer chemotherapeutic with fewer potential off-target effects. Recently, the crystal structure of GLUT1 in an inward open conformation was reported. Although this is an important achievement, a full understanding of the structural biology of facilitative glucose transport remains elusive. To date, there is no three-dimensional structure for GLUT4. We have generated a homology model for GLUT4 that we utilized to screen for drug-like compounds from a library of 18 million compounds. Despite 68% homology between GLUT1 and GLUT4, our virtual screen identified two potent compounds that were shown to target GLUT4 preferentially over GLUT1 and block glucose transport. Our results strongly bolster the utility of developing GLUT4-selective inhibitors as anti-cancer therapeutics.     

Essential Role for Zinc Transporter 2 (ZnT2)-mediated Zinc Transport in Mammary Gland Development and Function during Lactation

The zinc transporter ZnT2 (SLC30A2) imports zinc into vesicles in secreting mammary epithelial cells (MECs) and is critical for zinc efflux into milk during lactation. Recent studies show that ZnT2 also imports zinc into mitochondria and is expressed in the non-lactating mammary gland and non-secreting MECs, highlighting the importance of ZnT2 in general mammary gland biology. In this study we used nulliparous and lactating ZnT2-null mice and characterized the consequences on mammary gland development, function during lactation, and milk composition. We found that ZnT2 was primarily expressed in MECs and to a limited extent in macrophages in the nulliparous mammary gland and loss of ZnT2 impaired mammary expansion during development. Secondly, we found that lactating ZnT2-null mice had substantial defects in mammary gland architecture and MEC function during secretion, including fewer, condensed and disorganized alveoli, impaired Stat5 activation, and unpolarized MECs. Loss of ZnT2 led to reduced milk volume and milk containing less protein, fat, and lactose compared with wild-type littermates, implicating ZnT2 in the regulation of mammary differentiation and optimal milk production during lactation. Together, these results demonstrate that ZnT2-mediated zinc transport is critical for mammary gland function, suggesting that defects in ZnT2 not only reduce milk zinc concentration but may compromise breast health and increase the risk for lactation insufficiency in lactating women.     

Elucidation of Echovirus 30's Origin and Transmission during the 2012 Aseptic Meningitis Outbreak in Guangdong,China, through Continuing Environmental Surveillance

An aseptic meningitis outbreak occurred in Luoding City of Guangdong, China, in 2012, and echovirus type 30 (ECHO30) was identified as the major causative pathogen. Environmental surveillance indicated that ECHO30 was detected in the sewage of a neighboring city, Guangzhou, from 2010 to 2012 and also in Luoding City sewage samples (6/43, 14%) collected after the outbreak. In order to track the potential origin of the outbreak viral strains, we sequenced the VP1 genes of 29 viral strains from clinical patients and environmental samples. Sequence alignments and phylogenetic analyses based on VP1 gene sequences revealed that virus strains isolated from the sewage of Guangzhou and Luoding cities matched well the clinical strains from the outbreak, with high nucleotide sequence similarity (98.5% to 100%) and similar cluster distribution. Five ECHO30 clinical strains were clustered with the Guangdong environmental strains but diverged from strains from other regions, suggesting that this subcluster of viruses most likely originated from the circulating virus in Guangdong rather than having been more recently imported from other regions. These findings underscore the importance of long-term, continuous environmental surveillance and genetic analysis to monitor circulating enteroviruses.     

Within-Farm Changes in Dairy Farm-Associated Salmonella Subtypes and Comparison to Human Clinical Isolates in Michigan, 2000-2001 and 2009

Temporal changes in the distribution of Salmonella subtypes in livestock populations may have important impacts on human health. The first objective of this research was to determine the within-farm changes in the population of subtypes of Salmonella on Michigan dairy farms that were sampled longitudinally in 2000-2001 and again in 2009. The second objective was to determine the yearly frequency (2001 through 2012) of reported human illnesses in Michigan associated with the same subtypes. Comparable sampling techniques were used to collect fecal and environmental samples from the same 18 Michigan dairy farms in 2000-2001 and 2009. Serotypes, multilocus sequence types (STs), and pulsed-field gel electrophoresis (PFGE) banding patterns were identified for isolates from 6 farms where >1 Salmonella isolate was recovered in both 2000-2001 and 2009. The distribution of STs was significantly different between time frames (P < 0.05); only two of 31 PFGE patterns were identified in both time frames, and each was recovered from the same farm in each time frame. Previously reported within-farm decreases in the frequency of multidrug-resistant (MDR) Salmonella were due to recovery of MDR subtypes of S. enterica serotypes Senftenberg and Typhimurium in 2000-2001 and genetically distinct, pansusceptible subtypes of the same serotypes in 2009. The annual frequency of human illnesses between 2001 and 2012 with a PFGE pattern matching a bovine strain decreased for patterns recovered from dairy farms in 2000-2001 and increased for patterns recovered in 2009. These data suggest important changes in the population of Salmonella on dairy farms and in the frequency of human illnesses associated with cattle-derived subtypes.