Two separate teams of scientists have identified major challenges for the development of life in what has recently become one of the most famous exoplanet […]

The post There’s more to extraterrestrial life than planets in “habitable zone” orbits appeared first on Smithsonian Insider.

Only the Wing is a new book by Russell Lee that recounts Horten's epic quest to stabalize and control the all-wing aircraft.

The post New Book: “Only the Wing: Reimar Horten’s Epic Quest to Stabilize and Control the All-Wing Aircraft” appeared first on Smithsonian Insider.

Eric Peterman, Mindaugas Valius, and Rytis Prekeris

During mitotic cell division, the actomyosin cytoskeleton undergoes several dynamic changes that play key roles in progression through mitosis. While the regulators of cytokinetic ring formation and contraction are well-established, proteins that regulate cortical stability during anaphase and telophase have been understudied. Here, we describe a role for CLIC4 in regulating actin and actin-regulators at the cortex and cytokinetic cleavage furrow during cytokinesis. We first describe CLIC4 as a new component of the cytokinetic cleavage furrow that is required for successful completion of mitotic cell division. We also demonstrate that CLIC4 regulates the remodeling of sub-plasma membrane actomyosin network within the furrow by recruiting MST4 kinase and regulating ezrin phosphorylation. This work identifies and characterizes new molecular players involved in regulating cortex stiffness and blebbing during late stages of cytokinetic furrowing.

Laura O'Regan, Giancarlo Barone, Rozita Adib, Chang Gok Woo, Hui Jeong Jeong, Emily L. Richardson, Mark W. Richards, Patricia A.J. Muller, Spencer J. Collis, Dean A. Fennell, Jene Choi, Richard Bayliss, and Andrew M. Fry

EML4-ALK is an oncogenic fusion present in ~5% non-small cell lung cancers. However, alternative breakpoints in the EML4 gene lead to distinct variants with different patient outcomes. Here, we show in cell models that EML4-ALK variant 3 (V3), which is linked to accelerated metastatic spread, causes microtubule stabilization, formation of extended cytoplasmic protrusions and increased cell migration. It also recruits the NEK9 and NEK7 kinase to microtubules via the N-terminal EML4 microtubule-binding region. Overexpression of wild-type EML4 as well as constitutive activation of NEK9 also perturb cell morphology and accelerate migration in a microtubule-dependent manner that requires the downstream kinase NEK7 but not ALK activity. Strikingly, elevated NEK9 expression is associated with reduced progression-free survival in EML4-ALK patients. Hence, we propose that EML4-ALK V3 promotes microtubule stabilization through NEK9 and NEK7 leading to increased cell migration. This represents a novel actionable pathway that could drive metastatic disease progression in EML4-ALK lung cancer.

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.

Laurence Haren, Dorian Farache, Laurent Emorine, and Andreas Merdes

-tubulin is a major protein involved in the nucleation of microtubules in all eukaryotes. It forms two different complexes with proteins of the GCP family (gamma-tubulin complex proteins): -tubulin small complexes (TuSCs), containing -tubulin and GCPs 2 and 3, and -tubulin ring complexes (TuRCs), containing multiple TuSCs, in addition to GCPs 4, 5, and 6. Whereas the structure and assembly properties of TuSCs have been intensively studied, little is known about the assembly of TuRCs, and about the specific roles of GCPs 4, 5, and 6. Here, we demonstrate that two copies of GCP4 and one copy each of GCP5 and GCP6 form a salt-resistant sub-complex within the TuRC that assembles independently of the presence of TuSCs. Incubation of this sub-complex with cytoplasmic extracts containing TuSCs leads to the reconstitution of TuRCs that are competent to nucleate microtubules. In addition, we investigate sequence extensions and insertions that are specifically found at the amino-terminus of GCP6, and between the GCP6 grip1 and grip2 motifs, and we demonstrate that these are involved in the assembly or stabilization of the TuRC.

Recent analysis using DNA sequencing of ancient Roman pills found aboard a ship that sank in Italy’s Gulf of Baratti between 140 -120 B.C, has revealed that the medicines consist of material from simple garden plants, namely carrot, radish, parsley, celery, wild onion and cabbage.

The post DNA sequencing reveals simple vegetables in ancient Roman medicines appeared first on Smithsonian Insider.

Now the Global Plants Initiativeis catapulting biodiversity research to a new level by sharing these historic plant collections in a massive online database of high-resolution scans.

The post Online initiative makes massive database of herbarium specimens accessible worldwide appeared first on Smithsonian Insider.

The Smithsonian Environmental Research Center has created NEMESIS--National Estuarine and Marine Exotic Species Information System--an online public database that provides key information about the non-native marine species throughout the United States.

The post New invasive species database allows public to ID marine invaders with a home computer appeared first on Smithsonian Insider.

An error in an equation in the paper by Song et al. [Acta Cryst. (2019), C75, 1353–1358] is corrected.

The positional change of nitro­gen-7 of the RNA constituent guanosine to the bridgehead position-5 leads to the base-modified nucleoside 5-aza-7-de­aza­guanosine. Contrary to guanosine, this mol­ecule cannot form Hoogsteen base pairs and the Watson–Crick proton donor site N3—H becomes a proton-acceptor site. This causes changes in nucleobase recognition in nucleic acids and has been used to construct stable `all-purine' DNA and DNA with silver-mediated base pairs. The present work reports the single-crystal X-ray structure of 7-iodo-5-aza-7-de­aza­guanosine, C10H12IN5O5 (1). The iodinated nucleoside shows an anti conformation at the glycosylic bond and an N conformation (O4'-endo) for the ribose moiety, with an anti­periplanar orientation of the 5'-hy­droxy group. Crystal packing is controlled by inter­actions between nucleobase and sugar moieties. The 7-iodo substituent forms a contact to oxygen-2' of the ribose moiety. Self-pairing of the nucleobases does not take place. A Hirshfeld surface analysis of 1 highlights the contacts of the nucleobase and sugar moiety (O—H⋯O and N—H⋯O). The concept of pK-value differences to evaluate base-pair stability was applied to purine–purine base pairing and stable base pairs were predicted for the construction of `all-purine' RNA. Furthermore, the 7-iodo substituent of 1 was functionalized with benzo­furan to detect motional constraints by fluorescence spectroscopy.

During evaporation of natural and synthetic K–Mg–Cl brines, the formation of almost square plate-like crystals of potassium carnallite (potassium chloride magnesium dichloride hexa­hydrate) was observed. A single-crystal structure analysis revealed a monoclinic cell [a = 9.251 (2), b = 9.516 (2), c = 13.217 (4) Å, β = 90.06 (2)° and space group C2/c]. The structure is isomorphous with other carnallite-type com­pounds, such as NH4Cl·MgCl2·6H2O. Until now, natural and synthetic carnallite, KCl·MgCl2·6H2O, was only known in its ortho­rhom­bic form [a = 16.0780 (3), b = 22.3850 (5), c = 9.5422 (2) Å and space group Pnna].

Announcement cards and envelopes by designer Marc Friedland which are used by presenters at the Oscars to announce winners are on display at the food and decor preview Feb. 4, 2015 of this years Governors Ball, the post-Oscar celebration which follows the 87th Oscars ceremony on Feb. 22 in Hollywood.; Credit: Robyn Beck/AFP/Getty Images

Ready for your 2015 Oscars party? We've got printable Oscars ballots and the bingo cards you need to prove your superiority over your movie-loving friends during your Academy Awards viewing party. Here are the party printables you'll need to play along with Sunday's show, with TV coverage kicking off at 4 p.m. Pacific. (Get caught up on KPCC's 2015 Oscars coverage right here to have more fun and help make your picks!)

Printable official Oscars ballot

• Download, print, and play at home. Listen to "The Frame's" preview of the Academy Awards, see what "FilmWeek's" critics have to say about who will win, then make your own decisions on Sunday. Our crystal ball Oscars predictor/awards tracker can also help the prognostication efforts with a rundown of nominee buzz, awards already won, official trailers, photos and more.
• You can also play along with friends online on the official Academy Awards site or with the New York Times. (If you want to see KPCC's Mike Roe's picks and play against him in either online game, go here for the official site and here for the New York Times.)

2015 Oscars ballot

Printable Oscars bingo cards

• Download, print and play at home. Use our custom generator to create as many cards as you need for your party.
• How to play: Mark off each block when you hear these words or see these things happen during the Oscars telecast on Sunday. When you get five blocks in a row (horizontally, vertically, or diagonally) stand up and shout "OSCAR!!" Alternate rules: Play as a drinking game and for every block, take a sip. Finished a row? Finish your scotch.

Interactive Oscars bingo cards 

• WNYC pays tribute to the annual exercise in entertainment award show parody with a portable, computerized bingo. Play on your phone, iPad, computer or print a card. Refresh for new combinations.

This content is from Southern California Public Radio. View the original story at SCPR.org.

Georgi Dimchev
Apr 9, 2020; 133:jcs239020-jcs239020
Articles

Darkly colored, carotene-rich fruits and vegetables -- such as carrots, sweet potatoes, and broccoli -- provide the body with half as much vitamin A as previously thought.

A National Research Council committee asked to examine the scientific approaches used and conclusions reached by the Federal Bureau of Investigation during its investigation of the 2001 Bacillus anthracis mailings has determined that it is not possible to reach a definitive conclusion about the origins of the anthrax in letters mailed to New York City and Washington, D.C., based solely on the available scientific evidence.

Despite the importance of eyesight, millions of people grapple with undiagnosed or untreated vision impairments — ranging from mild conditions to total blindness — and eye and vision health remain relatively absent from national health priority lists, says a new report from the National Academies of Sciences, Engineering, and Medicine.

Clinical trials for genome editing of the human germline – adding, removing, or replacing DNA base pairs in gametes or early embryos – could be permitted in the future, but only for serious conditions under stringent oversight, says a new report from the National Academy of Sciences and the National Academy of Medicine.

The U.S. Coast Guard has safety regulatory oversight pertaining to vessel stability with standards that should respond to and improve with technological advances.

A commentary published in Nature calls for a moratorium on clinical uses of heritable human genome editing and the establishment of an international governance framework.

On May 10, the National Academies of Sciences, Engineering, and Medicine hosted a roundtable with senior representatives of academia, industry, and the federal government to exchange ideas about how to maximize the benefits of international science and technology collaboration while strengthening U.S. economic and national security.

An international commission has been convened by the U.S. National Academy of Medicine, the U.S. National Academy of Sciences, and the Royal Society of the U.K., with the participation of science and medical academies around the world, to develop a framework for scientists, clinicians, and regulatory authorities to consider when assessing potential clinical applications of human germline genome editing.

International thought leaders will join the next generation of engineers in London from Sept. 16 to 18 for the Global Grand Challenges Summit 2019. The summit aims to help inspire and equip future engineering leaders to address the rapidly evolving challenges of an unpredictable world.

Last week, the International Commission on the Clinical Use of Human Germline Genome Editing held its first public meeting at the National Academy of Sciences building in Washington, D.C.

The International Commission on the Clinical Use of Human Germline Genome Editing is tasked with identifying the scientific, medical, and ethical requirements to consider when assessing potential clinical applications of human germline genome editing — if society concludes that heritable human genome editing applications are acceptable.

When Sara Altschule took a 23andMe ancestry test, the results confirmed what she already suspected - She is 77 percent Ashkenazi Jewish.

The National Academies of Sciences, Engineering, and Medicine have been awarded a grant for $100,000 from Arcadia — a charitable fund of Lisbet Rausing and Peter Baldwin — to support the work of the Academies’ Roundtable on Aligning Incentives for Open Science.

Using ???cool??? materials to construct roads and walkways is an effective way of lowering urban temperatures to make cities more comfortable in hot weather. According to a recent study, surface temperatures were reduced by 12??C and ambient temperatures were reduced by 1.9??C after cool pavements were installed in a city park in Greece.