The new research reveals that from the period between 1100-1600 small agricultural settlements up and down the Delaware River Valley caused a 50-percent increase in sediment runoff into the Delaware River.

The post Study reveals environmental impact of American Indian farms centuries before Europeans arrived in North America appeared first on Smithsonian Insider.

One of the most challenging aspects of this research is simply studying these insects as they are falling, says Yanoviak, a tropical arthropod ecologist at the University of Arkansas, Little Rock. Small body size, rapid descent, and the long distances that they can fall, make accurate data taking a challenge.

The post Lofty experiments with gliding ants reveals secrets of their unusual flight appeared first on Smithsonian Insider.

Researchers from the Smithsonian Institution and the University of Florida have announced the discovery of a bone fragment, approximately 13,000 years old, in Florida with an incised image of a mammoth or mastodon.

The post Bone fragment is only Ice Age artwork from America to show a “proboscidean” appeared first on Smithsonian Insider.

A scientist from the Smithsonian Tropical Research Institute uses a pick to dislodge the fossil skull of an extinct toothed whale from sediments on the […]

The post Fossil skull of an extinct toothed whale excavated from Panamanian sediments appeared first on Smithsonian Insider.

Ecologists at the Smithsonian Environmental Research Center measure the growth rate of sedge grass in a brackish Chesapeake Bay marsh. Fed a diet rich in […]

The post SERC sedge grass experiment mimics predicted global-change scenario appeared first on Smithsonian Insider.

On Aug. 10, 1846, U.S. President James K. Polk signed the legislation that established the Smithsonian Institution as a trust administered by a Board of […]

The post Science at the Smithsonian: 165 years of scientific achievement appeared first on Smithsonian Insider.

As a coastal archaeologist and expert in prehistoric and historic settlement sites in the Chesapeake Bay region, Darrin Lowery of the Smithsonian’s National Museum of Natural History and University of Deleware, is carefully watching the effects of coastal erosion and rising sea levels on coastal archaeological sites.

The post Rising seas, development are altering prehistoric artifacts in the Chesapeake’s tidal zone appeared first on Smithsonian Insider.

When most people look at a forest, they see walking trails, deer yards, or firewood for next winter. But scientists at the Harvard Forest and […]

The post Development will reduce carbon stored in forests, Smithsonian & Harvard scientists predict appeared first on Smithsonian Insider.

Scientists from the Smithsonian and University of British Columbia have discovered a sensory organ in the chin of rorqual whales that communicates to the brain. It orchestrates the dramatic adjustments needed in jaw position and throat-pouch expansion to make lunge feeding successful

The post Scientists discover sensory organ in baleen whales that choreographs movement of their massive jaws and throat-pouch appeared first on Smithsonian Insider.

The Smithsonian Astrophysical Observatory has been awarded a NASA project to build the Tropospheric Emissions: Monitoring of Pollution (TEMPO) instrument. TEMPO will measure North American air pollution, from Mexico City to the Canadian tar/oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution.

The post NASA funds Smithsonian Astrophysical Observatory instrument to track North American air pollution appeared first on Smithsonian Insider.

Using echolocation alone the bats found, identified and captured insects perched motionless and silent on the leaves of plants.

The post Common tropical bat uses echolocation with precision previously considered impossible, new experiments reveal appeared first on Smithsonian Insider.

Marmosets on track for obesity appeared to be more efficient in their feeding behavior. “Although all animals consumed the same amount of liquid, the ones […]

The post Obese marmosets are more developmentally advanced as infants, study shows appeared first on Smithsonian Insider.

Recent spectroscopic analysis of macaroni penguin (Eudyptes chrysolophus) crest feathers and king penguin (Aptenodytes patagonicus) neck feathers have shown they contain a yellow pigment that […]

The post Yellow pigment in penguin feathers is chemically distinct, spectroscopic studies reveal appeared first on Smithsonian Insider.

Rope, golf balls, sweat pants, bottles and aluminum cans are a few of the discarded items biologist Matt Klope says he has found inside the […]

The post Gray whale specimen an important addition to Natural History Museum collections appeared first on Smithsonian Insider.

Sometime during the Middle Eocene a prehistoric mosquito slurped down a final blood meal then died and sank to the bottom of a pond in […]

The post Blood molecules preserved for millions of years in abdomen of fossil mosquito appeared first on Smithsonian Insider.

A research team from the Smithsonian and Arizona State University have developed a new, non-destructive method using spectroscopic analysis to help unravel the complex chemistry […]

The post Feathers yield mysteries of pigment chemistry to spectroscopic analysis appeared first on Smithsonian Insider.

“Early Women in Science” is an online exhibition of 16 women scientists who began their work before 1922. A Biodiversity Heritage Library exhibition, it profiles forward-thinking […]

The post “Early Women in Science” Profiles Trailblazing Women appeared first on Smithsonian Insider.

Caitlin Burrell, research scientist at the Smithsonian Conservation Biology Institute, returned from China last night April 20, with frozen giant panda semen that had been […]

The post Panda Semen from China arrives at Zoo appeared first on Smithsonian Insider.

The world’s coasts are home to more than 70 percent of the human population and experience intense development as a result. The rate of environmental […]

The post Smithsonian Environmental Research Center Marks 50 Years of Making a Difference appeared first on Smithsonian Insider.

New data just published in the journal Marine Mammal Science may help save the whales, or at least a good many of them. Using vertebrae […]

The post New study may help free whales from fishing rope entanglement appeared first on Smithsonian Insider.

The Inka Empire is one of the greatest civilizations in the Western Hemisphere, spanning from the 13th century until the Spanish invasion in 1532. To […]

The post 5 Reasons the Inka Road is one of the Greatest Achievements in Engineering appeared first on Smithsonian Insider.

Smithsonian scientists and colleagues have discovered a new genus and species of river dolphin that has long been extinct. They made the discovery after carefully […]

The post Fossil Specimen Reveals a New Species of Ancient River Dolphin appeared first on Smithsonian Insider.

Here’s some good news that should hit you in the gut. A team of scientists searching thousands of environments for bacteria that produce the deadly […]

The post Survey pinpoints where toxic mercury accumulates in world environments appeared first on Smithsonian Insider.

The pink-headed duck was no lucky duck. In 1948 a single specimen of this waterfowl, Rhodonessa caryophyllacea, was donated to the Division of Birds of […]

The post Carotenoid pigments make extinct duck a rare bird indeed appeared first on Smithsonian Insider.

(Study is one of dozens to be presented by bird scientists this week at the 2016 North American Ornithological Conference in Washington, D.C.) To catch tuna […]

The post Fishing gear entanglements of marine birds is focus of Smithsonian ecologist’s study appeared first on Smithsonian Insider.

Like many predators, the fringe-lipped bat primarily uses its hearing to find its prey, but with human-generated noise on the rise, scientists are examining how […]

The post Bats Use Second Sense to Hunt Prey in Noisy Environments appeared first on Smithsonian Insider.

Thanksgiving Menu, 1905 Smithsonian Snapshot celebrates the Thanksgiving season with this 1905 Thanksgiving menu by George Elbert Burr from the Smithsonian American Art Museum. In […]

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“Think of a lion shrunk to the size of a mouse that needs to eat every 20 minutes or so.” That is a shrew, says […]

The post New Costa Rican shrew species named from a single specimen found 44 years ago appeared first on Smithsonian Insider.

Finding clean ways to store water is a challenge that humans have faced for millennia. In a new paper in Environmental Health, anthropologist Sabrina Sholts […]

The post Study shows ancient California Indians risked toxins from bitumen-coated bottles appeared first on Smithsonian Insider.

Hundreds of experiments have shown biodiversity fosters healthier, more productive ecosystems. But many experts doubted whether these experiments would hold up in the real world. […]

The post In the wild, biodiversity’s power surpasses what experiments predict appeared first on Smithsonian Insider.

The center of our Galaxy has been intensely studied for many years, but it still harbors surprises for scientists. A snake-like structure lurking near our […]

The post Cosmic filament probes our galaxy’s giant black hole appeared first on Smithsonian Insider.

Every day, astronomers at the Harvard-Smithsonian Center for Astrophysics depend on computers to help them solve the mysteries of the universe, just as they did […]

The post Underpaid women “computers” mapped the universe in the 19th century appeared first on Smithsonian Insider.

Leucocyte common antigen-related protein (LAR) is a post-synaptic type I transmembrane receptor protein that is important for neuronal functionality and is genetically coupled to neuronal disorders such as attention deficit hyperactivity disorder (ADHD). To understand the molecular function of LAR, structural and biochemical studies of protein fragments derived from the ectodomain of human LAR have been performed. The crystal structure of a fragment encompassing the first four FNIII domains (LARFN1–4) showed a characteristic L shape. SAXS data suggested limited flexibility within LARFN1–4, while rigid-body refinement of the SAXS data using the X-ray-derived atomic model showed a smaller angle between the domains defining the L shape compared with the crystal structure. The capabilities of the individual LAR fragments to interact with heparin was examined using microscale thermophoresis and heparin-affinity chromatography. The results showed that the three N-terminal immunoglobulin domains (LARIg1–3) and the four C-terminal FNIII domains (LARFN5–8) both bound heparin, while LARFN1–4 did not. The low-molecular-weight heparin drug Innohep induced a shift in hydrodynamic volume as assessed by size-exclusion chromatography of LARIg1–3 and LARFN5–8, while the chemically defined pentameric heparin drug Arixtra did not. Together, the presented results suggest the presence of an additional heparin-binding site in human LAR.

Archan Chakraborty, Wei-Cheng Lin, Yu-Tsun Lin, Kuang-Jing Huang, Pei-Yu Wang, Yi-Feng Chang, Hsiang-Iu Wang, Kung-Ting Ma, Chun-Yen Wang, Xuan-Rong Huang, Yen-Hsien Lee, Bi-Chang Chen, Ya-Ju Hsieh, Kun-Yi Chien, Tzu-Yang Lin, Ji-Long Liu, Li-Ying Sung, Jau-Song Yu, Yu-Sun Chang, and Li-Mei Pai

Under metabolic stress, cellular components can assemble into distinct membraneless organelles for adaptation. One such example is cytidine 5'-triphosphate synthase (CTPS), which forms filamentous structures under glutamine deprivation. We have previously demonstrated that histidine (His)-mediated methylation regulates the formation of CTPS filaments to suppress enzymatic activity and preserve the CTPS protein under Gln deprivation, which promotes cancer cell growth after stress alleviation. However, it remains unclear where and how these enigmatic structures are assembled. Using CTPS-APEX2-mediated in vivo proximity labeling, we found that SNAP29 regulates the spatiotemporal filament assembly of CTPS along the cytokeratin network in a keratin 8 (KRT8)-dependent manner. Knockdown of synaptosome-associated protein 29 (SNAP29) interfered with assembly and relaxed the filament-induced suppression of CTPS enzymatic activity. Furthermore, APEX2 proximity labeling of keratin 18 (KRT18) revealed a spatiotemporal association of SNAP29 with cytokeratin in response to stress. Super-resolution imaging suggests that during CTPS filament formation, SNAP29 interacts with CTPS along the cytokeratin network. This study links the cytokeratin network to the regulation of metabolism by compartmentalization of metabolic enzymes during nutrient deprivation.

Olga Kopach, Noemi Esteras, Selina Wray, Dmitri A. Rusakov, and Andrey Y. Abramov

Frontotemporal dementia and parkinsonism (FTDP-17) caused by the 10+16 splice-site mutation in the MAPT provides an established platform to model tau-related dementia in vitro. Human iPSC-derived neurons have been shown to recapitulate the neurodevelopmental profile of tau pathology during in vitro corticogenesis as in the adult human brain. However, the neurophysiological phenotype of these cells has remained unknown, leaving unanswered questions over the functional relevance and the gnostic power of this disease model. Here we used electrophysiology to explore the membrane properties and intrinsic excitability of the generated neurons to find that human cells mature by ~150 days of neurogenesis to become compatible with matured cortical neurons. In earlier FTDP-17, neurons, however, exhibited a depolarized resting membrane potential associated with increased resistance and reduced voltage-gated Na⁺- and K⁺-channel-mediated conductance. The Na_v1.6 protein was reduced in FTDP-17. These led to a reduced cell capability of induced firing and changed action potential waveform in FTDP-17. The revealed neuropathology may thus contribute to the clinicopathological profile of the disease. This sheds new light on the significance of human models of dementia in vitro.

Karolina Losenkova, Mariachiara Zuccarini, Marika Karikoski, Juha Laurila, Detlev Boison, Sirpa Jalkanen, and Gennady G. Yegutkin

Extracellular adenosine mediates diverse anti-inflammatory, angiogenic and vasoactive effects and becomes an important therapeutic target for cancer, which has been translated into clinical trials. This study was designed to comprehensively assess adenosine metabolism in prostate and breast cancer cells. We identified cellular adenosine turnover as a complex cascade, comprised of (a) the ectoenzymatic breakdown of ATP via sequential nucleotide pyrophosphatase/phosphodiesterase-1, ecto-5’-nucleotidase/CD73 and adenosine deaminase reactions, and ATP re-synthesis through counteracting adenylate kinase and nucleoside diphosphokinase; (b) the uptake of nucleotide-derived adenosine via equilibrative nucleoside transporters; and (c) the intracellular adenosine phosphorylation into ATP by adenosine kinase and other nucleotide kinases. The exposure of cancer cells to 1% O₂ for 24 hours triggered ~2-fold up-regulation of CD73, without affecting nucleoside transporters, adenosine kinase activity and cellular ATP content. The ability of adenosine to inhibit the tumor-initiating potential of breast cancer cells via receptor-independent mechanism was confirmed in vivo using a xenograft mouse model. The existence of redundant pathways controlling extracellular and intracellular adenosine provides a sufficient justification for reexamination of the current concepts of cellular purine homeostasis and signaling in cancer.

M. Pinar and M. A. Penalva

TRAnsport Protein Particle (TRAPP) complexes regulate membrane traffic. TRAPPII and TRAPPIII share a core hetero-heptamer, also denoted TRAPPI. In fungi TRAPPIII and TRAPPII mediate GDP exchange on RAB1 and RAB11, respectively, regulating traffic across the Golgi, with TRAPPIII also activating RAB1 in autophagosomes. Our finding that Aspergillus nidulans TRAPPII can be assembled by addition of a TRAPPII-specific subcomplex onto core TRAPP prompted us to investigate the possibility that TRAPPI/TRAPPIII already residing in the Golgi matures into TRAPPII to determine a RAB1-to-RAB11 conversion as Golgi cisternae progress from early Golgi to TGN identity. By time-resolved microscopy we determine that the TRAPPII reporter Trs120/TRAPPC9 is recruited to existing TGN cisternae slightly before RAB11 arrives, and resides for~45 sec on them before cisternae tear off into RAB11 secretory carriers. Notably, the core TRAPP reporter Bet3/TRAPPC3 was not detectable in early Golgi cisternae, being instead recruited to TGN cisternae simultaneously with Trs120/TRAPPC9, indicating en bloc recruitment of TRAPPII to the Golgi and arguing strongly against the TRAPP maturation model.

Westley Heydeck, Brian A. Bayless, Alexander J. Stemm-Wolf, Eileen T. O'Toole, Amy S. Fabritius, Courtney Ozzello, Marina Nguyen, and Mark Winey

Basal bodies (BBs) are microtubule-based organelles that template and stabilize cilia at the cell surface. Centrins ubiquitously associate with BBs and function in BB assembly, maturation, and stability. Human POC5 (hPOC5) is a highly conserved centrin-binding protein that binds centrins through Sfi1p-like repeats and is required for building full-length, mature centrioles. Here, we use the BB-rich cytoskeleton of Tetrahymena thermophila to characterize Poc5 BB functions. Tetrahymena Poc5 (TtPoc5) uniquely incorporates into assembling BBs and is then removed from mature BBs prior to ciliogenesis. Complete genomic knockout of TtPOC5 leads to a significantly increased production of BBs yet a markedly reduced ciliary density, both of which are rescued by reintroduction of TtPoc5. A second Tetrahymena POC5-like gene, SFR1, is similarly implicated in modulating BB production. When TtPOC5 and SFR1 are co-deleted, cell viability is compromised, and levels of BB overproduction are exacerbated. Overproduced BBs display defective transition zone formation and a diminished capacity for ciliogenesis. This study uncovers a requirement for Poc5 in building mature BBs, providing a possible functional link between hPOC5 mutations and impaired cilia.

Thomas O'Loughlin, Antonina J. Kruppa, Andre L. R. Ribeiro, James R. Edgar, Abdulaziz Ghannam, Andrew M. Smith, and Folma Buss

Optineurin (OPTN) is a multifunctional protein involved in autophagy, secretion as well as NF-B and IRF3 signalling and OPTN mutations are associated with several human diseases. Here we show that, in response to viral RNA, OPTN translocates to foci in the perinuclear region, where it negatively regulates NF-B and IRF3 signalling pathways and downstream pro-inflammatory cytokine secretion. These OPTN foci consist of a tight cluster of small membrane vesicles, which are positive for ATG9A. Disease mutations linked to POAG cause aberrant foci formation in the absence of stimuli, which correlates with the ability of OPTN to inhibit signalling. Using proximity labelling proteomics, we identify the LUBAC complex, CYLD and TBK1 as part of the OPTN interactome and show that these proteins are recruited to this OPTN-positive perinuclear compartment. Our work uncovers a crucial role for OPTN in dampening NF-B and IRF3 signalling through the sequestration of LUBAC and other positive regulators in this viral RNA-induced compartment leading to altered pro-inflammatory cytokine secretion.

At 7:05 pm (EDT), Thursday, Sept. 8, NASA plans to launch a spacecraft to a near-Earth asteroid named Bennu. Among that spacecraft’s five instruments is […]

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Odile Madden knows a lot about plastic. A materials scientist with the Smithsonian Museum Conservation Institute, she has spent the past eight years studying plastics […]

The post Microplastics in our environment: A conversation with Odile Madden, Smithsonian plastics scientist appeared first on Smithsonian Insider.

in Outlook Express and Thunderbird

The post Device at the Smithsonian Environmental Research Center examines how phytoplankton would react if the ozone layer vanished appeared first on Smithsonian Insider.

Meet Rachel Collin, a staff scientist and director of the Bocas Research Station at the Smithsonian Tropical Research Institute in Panama. Rachel studies the evolution of marine gastropods (snails) and oversees multiple disciplines of marine biology at the Collin Lab in Bocas del Toro.

The post Meet Our Scientist: Rachel Collin, an expert in the evolution and development of snails who is working in Panama appeared first on Smithsonian Insider.

Speeding Up Science from Facebook Stories on Vimeo. In January 2011, Oregon State University ichthyologist Brian Sidlauskas led a research expedition into the little-known Cuyuni […]

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The post How do paleontologists reconstruct environments from the ancient past? appeared first on Smithsonian Insider.

The post Samuel P. Langley, Secretary of the Smithsonian, and his development of the ill-fated Aerodrome A appeared first on Smithsonian Insider.

The Smithsonian’s National Museum of Natural History released a new mobile app “Skin and Bones” Jan. 13. The free app is available for download in […]

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