One of the primary features that distinguish hominids such as chimpanzees, gorillas and humans from the rest of the animal kingdom are uniquely dexterous hands. […]

The post Did ripening fruit help hominids develop complex hands? appeared first on Smithsonian Insider.

The planet’s last stronghold of wild cheetahs (Acinonyx jubatus) is losing genetic diversity at an alarming rate according to a new study from the Smithsonian […]

The post Smithsonian Study reveals Decline of Genetic Diversity in Wild Cheetahs appeared first on Smithsonian Insider.

Thanks to a recent reassessment of specimens preserved in jars of alcohol at the Smithsonian’s National Museum of Natural History, New Hampshire is now on […]

The post Discovery in Smithsonian collection broadens understanding of rare North American leech appeared first on Smithsonian Insider.

Meet Scorpaenodes barrybrowni is a scorpionfish species newly discovered by Smithsonian scientists using a manned submersible in the deep-reef waters of the Caribbean island of Curaçao. It […]

The post New bright orange-red scorpionfish discovered deep in Caribbean appeared first on Smithsonian Insider.

The Smithsonian Conservation Biology Institute (SCBI) hatched its first hooded crane chick June 14. The chick was born as the result of artificial insemination. The […]

The post First hooded crane hatches @ SCBI appeared first on Smithsonian Insider.

President Jimmy Carter, an avid birder, talks about the importance of bird conservation and why birds really matter. Step outside your house in the morning […]

The post Why Birds Really Matter: President Jimmy Carter appeared first on Smithsonian Insider.

In an age of one-hour delivery and overnight shipping, a corner of the country still gets its mail by mule. That’s right. For a small […]

The post In the Grand Canyon, the U.S. Postal Service still delivers mail by mule appeared first on Smithsonian Insider.

There’s something exciting and strange about having an idea. It can come suddenly. Unexpectedly. Randomly. Intensely. Ideas can uninvitingly appear full-forced and bright—like the cliché […]

The post Making the Smithsonian’s New “Sidedoor” podcast series a reality appeared first on Smithsonian Insider.

In 1969, 60 to 100 peacock bass imported from Buga, Colombia, were introduced into a pond in Panama for sport fishing. Several individuals escaped. By […]

The post Peacock bass invasion Had devastating, long-term impact on Panama’s Fish appeared first on Smithsonian Insider.

Food is scarce in the deep, dark regions of the ocean where barbeled dragonfishes and their relatives dwell. Known as the Stomiidae, some of these […]

The post Odd anatomy: flexible joint between skull and spine allow dragonfish to open wide appeared first on Smithsonian Insider.

New species don’t just spring out of thin air. Speciation, the evolutionary process by which new and distinct species arise, usually takes millions of years. […]

The post Simultaneous hermaphrodites: Understanding Speciation in fish called “hamlets” appeared first on Smithsonian Insider.

A bizarre change occurs in the mouth of a humpback whale during its development in the womb. Several dozen tooth buds sprout in a row […]

The post Paleo-detectives energize great whale mystery: how & when baleen evolved appeared first on Smithsonian Insider.

Whales from both poles migrate long distances to breed in tropical waters. Smithsonian scientist Hector M. Guzman and Fernando Félix at the Salinas Whale Museum […]

The post Whale tagging in Southeast Pacific provides data for species protection appeared first on Smithsonian Insider.

Four years after conservationists relocated 570 desert tortoises (Gopherus agassizii) in California from a threatened habitat to a new nearby location, the tortoises outwardly appeared […]

The post Smithsonian Study shows relocated desert tortoises reproduce at lower rate appeared first on Smithsonian Insider.

Sometimes there’s just no telling what will turn up at the local market. Fish biologist Jeff Williams of the Smithsonian’s National Museum of Natural History […]

The post Surprise: Distinctive new surgeonfish species makes an improbable debut appeared first on Smithsonian Insider.

The world’s most indestructible species, the tardigrade, an eight-legged micro-animal, also known as the water bear, will survive until the Sun dies, according to a […]

The post Study determines microscopic water bears will be Earth’s last survivors appeared first on Smithsonian Insider.

In a new study in which one of humankind’s most high-tech tools was used to analyze one of its most primitive, scientists have uncovered evidence […]

The post Laser beams unveil secrets locked inside primitive stone spear points appeared first on Smithsonian Insider.

Covered in sharp spines, when harassed the porcupine fish inflates like a balloon. Think of a small soccer ball bristling all over with nails. Most predators […]

The post Indestructible jaws from ancient, extinct porcupine fish reveal new species appeared first on Smithsonian Insider.

In conflicts between predators and prey, speed is a decided advantage, and evolution has given the trap-jaw ant a distinct advantage with spring-loaded jaws that […]

The post Locked and loaded: unique trigger design fires this ant’s snapping jaws appeared first on Smithsonian Insider.

Cats are notoriously fickle—purring in your lap one second, then swiping you with an indignant claw the next. One thing is certain however when it […]

The post Eons before viral kitten videos, ancient Egyptians adored cats appeared first on Smithsonian Insider.

Three former scientists from the Smithsonian’s National Zoological Park–Ellen Lamirande, Don Nichols, and Allan Pessier–were honored at the sixth annual Golden Goose Award ceremony at […]

The post Zoo scientists honored at Golden Goose appeared first on Smithsonian Insider.

A bat specimen collected in France at the end of World War I, since housed in the collections of the Smithsonian’s National Museum of Natural […]

The post DNA on 100-year-old bat from France may help fight deadly fungus in North America appeared first on Smithsonian Insider.

A new project using data from NASA’s Chandra X-ray Observatory and other telescopes allows people to navigate through real data of the remains of an […]

The post A new stellar X-ray “reality” show debuts appeared first on Smithsonian Insider.

A new study from the Smithsonian Conservation Biology Institute (SCBI) is helping make headway in an area of animal management that has historically proven challenging: […]

The post Early indicator of cheetah pregnancy identified appeared first on Smithsonian Insider.

According to a new survey of residents living near two major national parks in Panama, jaguars deserve increased protection. Nature and wildlife are considered national […]

The post Jaguar conservation depends on neighbor attitudes appeared first on Smithsonian Insider.

Astronomers had a mystery on their hands. No matter where they looked, from inside the Milky Way to distant galaxies, they observed a puzzling glow […]

The post GBT Detection Unlocks Exploration of ‘Aromatic’ Interstellar Chemistry appeared first on Smithsonian Insider.

In 1854, a curious-looking spider was found preserved in 50 million-year-old amber. With an elongated neck-like structure and long mouthparts that protruded from the “head” […]

The post These newly discovered pelican spiders will make you want to visit Madagascar appeared first on Smithsonian Insider.

There are currently more than 3,500 confirmed known exoplanets thanks to the remarkable sensitivity of the Kepler spacecraft and to technological advances in space and […]

The post Astronomers detect comets transiting distant stars appeared first on Smithsonian Insider.

Swimming in the frigid waters of the Arctic and surfacing in narrow gaps in the sea ice to breathe, the narwhal is one of the […]

The post Meet the world’s weirdest whale 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.

In the early 20th century, Canada geese were considered endangered in the U.S. So in the 1950s and 1960s, birds from the Midwest were released […]

The post Study of bacteria inside guts of wild Canada geese shows greater danger than earlier studies exposed appeared first on Smithsonian Insider.

When the heat and humidity of the Washington, D.C. summer sends its residents scrambling for air conditioning and iced coffee, the animal care specialists at […]

The post How do National Zoo animals beat the heat? Bloodsicles and other frozen delicacies appeared first on Smithsonian Insider.

When many people think of the Chesapeake Bay, one of the first creatures that comes to mind is the iconic blue crab. But parts of […]

The post Smithsonian scientists become shark detectives to track species in the Chesapeake Bay appeared first on Smithsonian Insider.

The outer membrane of Gram-negative bacteria is highly impermeable to hydrophilic molecules of larger than 600 Da, protecting these bacteria from toxins present in the environment. In order to transport nutrients across this impermeable membrane, Gram-negative bacteria utilize a diverse family of outer-membrane proteins called TonB-dependent transporters. The majority of the members of this family transport iron-containing substrates. However, it is becoming increasingly clear that TonB-dependent transporters target chemically diverse substrates. In this work, the structure and phylogenetic distribution of the TonB-dependent transporter YncD are investigated. It is shown that while YncD is present in some enteropathogens, including Escherichia coli and Salmonella spp., it is also widespread in Gammaproteobacteria and Betaproteobacteria of environmental origin. The structure of YncD was determined, showing that despite a distant evolutionary relationship, it shares structural features with the ferric citrate transporter FecA, including a compact positively charged substrate-binding site. Despite these shared features, it is shown that YncD does not contribute to the growth of E. coli in pure culture under iron-limiting conditions or with ferric citrate as an iron source. Previous studies of transcriptional regulation in E. coli show that YncD is not induced under iron-limiting conditions and is unresponsive to the ferric uptake regulator (Fur). These observations, combined with the data presented here, suggest that YncD is not responsible for the transport of an iron-containing substrate.

Death-associated protein kinase 1 (DAPK1) is a serine/threonine protein kinase that regulates apoptosis and autophagy. DAPK1 is considered to be a therapeutic target for amyloid-β deposition, endometrial adenocarcinomas and acute ischemic stroke. Here, the potent inhibitory activity of the natural anthraquinone purpurin against DAPK1 phosphorylation is shown. Thermodynamic analysis revealed that while the binding affinity of purpurin is similar to that of CPR005231, which is a DAPK1 inhibitor with an imidazopyridazine moiety, the binding of purpurin was more enthalpically favorable. In addition, the inhibition potencies were correlated with the enthalpic changes but not with the binding affinities. Crystallographic analysis of the DAPK1–purpurin complex revealed that the formation of a hydrogen-bond network is likely to contribute to the favorable enthalpic changes and that stabilization of the glycine-rich loop may cause less favorable entropic changes. The present findings indicate that purpurin may be a good lead compound for the discovery of inhibitors of DAPK1, and the observation of enthalpic changes could provide important clues for drug development.

This user-friendly, portable, and extensive identification guide features large color illustrations of more than 900 species; the first range maps published to show the distribution of Panama's birds and concise text that describes field marks for identification, as well as habitat, behavior, and vocalizations.

The post Smithsonian ornithologist publishes new guide to the birds of Panama appeared first on Smithsonian Insider.

As command module pilot for the Apollo 15 mission to the moon in 1971, Al Worden spent six days orbiting the moon, including three days completely alone, the most isolated human in existence. In Falling to Earth, Worden tells for the first time the full story around the dramatic events that shook NASA and ended his spaceflight career.

The post “Falling to Earth: An Apollo 15 Astronaut’s Journey to the Moon” by Al Worden with Francis French appeared first on Smithsonian Insider.

In this fun, accessible and informative book, ichthyologists Gene Helfman, professor emeritus at the University of Georgia, and Bruce Collette, of the Division of Fishes at the Smithsonian’s National Museum of Natural History, provide accurate, entertaining, and sometimes surprising answers to more than 100 common and not-so-common questions.

The post New Book: “Fishes: The Animal Answer Guide” appeared first on Smithsonian Insider.

When it comes to the birds of South Asia, Pamela Rasmussen wrote the book on it. Literally. Twice.

The post New Book: “Birds of South Asia: The Ripley Guide” appeared first on Smithsonian Insider.

Bipasha Dey and Richa Rikhy

Cell shape morphogenesis from spherical to polygonal occurs in epithelial cell formation in metazoan embryogenesis. In syncytial Drosophila embryos, the plasma membrane incompletely surrounds each nucleus and is organized as a polygonal epithelial-like array. Each cortical syncytial division cycle shows circular to polygonal plasma membrane transition along with furrow extension between adjacent nuclei from interphase to metaphase. In this study, we assess the relative contribution of DE-cadherin and Myosin II at the furrow for polygonal shape transition. We show that polygonality initiates during each cortical syncytial division cycle when the furrow extends from 4.75 to 5.75 µm. Polygon plasma membrane organization correlates with increased junctional tension, increased DE-cadherin and decreased Myosin II mobility. DE-cadherin regulates furrow length and polygonality. Decreased Myosin II activity allows for polygonality to occur at a lower length than controls. Increased Myosin II activity leads to loss of lateral furrow formation and complete disruption of polygonal shape transition. Our studies show that DE-cadherin-Myosin II balance regulates an optimal lateral membrane length during each syncytial cycle for polygonal shape transition.

Xian Hu, Salma Jalal, Michael Sheetz, Oddmund Bakke, and Felix Margadant

Despite progress made in confocal microscopy, even fast systems still have insufficient temporal resolution for detailed live cell volume imaging, such as tracking rapid movement of membrane vesicles in three-dimensional space. Depending on the shortfall, this may result in undersampling and/or motion artifacts that ultimately limit the quality of the imaging data. By sacrificing detailed information in the Z-direction, we propose a new imaging modality that involves capturing fast "projections" from the field of depth which shortens imaging time by approximately an order of magnitude as compared to standard volumetric confocal imaging. With faster imaging, radiation exposure to the sample is reduced, resulting in less fluorophore photobleaching and potential photodamage. The implementation minimally requires two synchronized control signals that drive a piezo stage and trigger the camera exposure. The device generating the signals has been tested on spinning disk confocals and instant structured-illumination-microscopy (iSIM) microscopes. Our calibration images show that the approach provides highly repeatable and stable imaging conditions that enable photometric measurements of the acquired data, in both standard live imaging and super-resolution modes.

Kristina Drizyte-Miller, Jing Chen, Hong Cao, Micah B. Schott, and Mark A. McNiven

Epithelial cells such as liver-resident hepatocytes rely heavily on the Rab family of small GTPases to perform membrane trafficking events that dictate cell physiology and metabolism. Not surprisingly, disruption of several Rabs can manifest in metabolic diseases or cancer. Rab32 is expressed in many secretory epithelial cells but its role in cellular metabolism is virtually unknown. In this study, we find that Rab32 associates with lysosomes and regulates proliferation and cell size of Hep3B hepatoma and HeLa cells. Specifically, we identify that Rab32 supports mTORC1 signaling under basal and amino acid stimulated conditions. Consistent with inhibited mTORC1, an increase in nuclear TFEB localization and lysosome biogenesis is also observed in Rab32-depleted cells. Finally, we find that Rab32 interacts with mTOR kinase and that loss of Rab32 reduces the association of mTOR and mTORC1 pathway proteins with lysosomes, suggesting that Rab32 regulates lysosomal mTOR trafficking. In summary, these findings suggest that Rab32 functions as a novel regulator of cellular metabolism through supporting mTORC1 signaling.

Hem Sapkota, Jonathan D. Wren, and Gary J. Gorbsky

Centrosomes focus microtubules to promote mitotic spindle bipolarity, a critical requirement for balanced chromosome segregation. Comprehensive understanding of centrosome function and regulation requires a complete inventory of components. While many centrosome components have been identified, others may yet remain undiscovered. We have used a bioinformatics approach, based on "guilt by association" expression to identify novel mitotic components among the large group of predicted human proteins that have yet to be functionally characterized. Here we identify Chondrosarcoma-Associated Gene 1 (CSAG1) in maintaining centrosome integrity during mitosis. Depletion of CSAG1 disrupts centrosomes and leads to multipolar spindles more effectively in cells with compromised p53 function. Thus, CSAG1 may reflect a class of "mitotic addiction" genes whose expression is more essential in transformed cells.

Victor J. F. Kitano, Yoko Ohyama, Chiyomi Hayashida, Junta Ito, Mari Okayasu, Takuya Sato, Toru Ogasawara, Maki Tsujita, Akemi Kakino, Jun Shimada, Tatsuya Sawamura, and Yoshiyuki Hakeda

Osteoporosis is associated with vessel diseases attributed to hyperlipidemia, and bone resorption by multinucleated osteoclasts is related to lipid metabolism. In this study, we generated low-density lipoprotein receptor (LDLR)/lectin-like oxidized LDL receptor-1 (LOX-1) double knockout (dKO) mice. We found that, like LDLR single KO (sKO), LDLR/LOX-1 dKO impaired cell-cell fusion of osteoclast-like cells (OCLs). LDLR/LOX-1 dKO and LDLR sKO preosteoclasts exhibited decreased uptake of LDL. The cell surface cholesterol levels of both LDLR/LOX-1 dKO and LDLR sKO osteoclasts were lower than the levels of wild-type OCLs. Additionally, the amount of phosphatidylethanolamine (PE) on the cell surface was attenuated in LDLR/LOX-1 dKO and LDLR sKO pre-OCLs, while the PE distribution in wild-type OCLs was concentrated on the filopodia in contact with neighboring cells. Abrogation of the ATP binding cassette G1 (ABCG1) transporter, which transfers PE to the cell surface, caused decreased PE translocation to the cell surface and subsequent cell-cell fusion. The findings of this study indicate the involvement of a novel cascade (LDLR~ABCG1~PE translocation to cell surface~cell-cell fusion) in multinucleation of OCLs.

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.