Pensoft blog - Part 69

Drug resistance of cancer cells crucially affected by expression levels of ABC-transporters

How is drug resistance of cancer cells affected by ABC-transporters? A new research paper, published in the open access journal BioDiscovery, looks at the complex relationship between the second generation of tyrosine kinase inhibitor (TKI) – Dasatinib (DAS), and the expression of ATP-binding cassette (ABC) transporters, ABCB1 and ABCG2, to assess whether these drug transporters might compromise therapeutic effect.

Cancer enabled “targeted” treatment is an effective method with a minimal damage for healthy cells. Targeted therapy brought about a revolution in cancer treatment in the last decades by utilising rationally designed drugs that interfere with specific molecules (molecular targets) essential for proliferation and survival of malignant cells.

While DAS represents excellent choice for the treatment of chronic myeloid leukemia resistant to imatinib, recent laboratory studies suggested that antiproliferative effect of DAS might be significantly reduced when overexpression of the ATP-binding ABC transporters, ABCB1 and ABCG2 comes into the equation.

“Despite the importance of this relationship, it was still unclear whether these drug transporters might compromise therapeutic effect of DAS in clinic,” explains Dr. Petr Mlejnek, Palacky University Olomouc, Czech Republic. “Believing that the drug transporter expression level is a crucial factor that affects the results and thus may help to explain the existing controversy we decided to study relationship between expression levels of ABCB1 and ABCG2 and cell resistance to DAS in vitro.”

In their study Dr. Petr Mlejnek and his team from the Palacky University Olomouc, Czech Republic observed that the expression level of the studied ABC-transporter is an important factor that affects the cell resistance. While the antiproliferative and pro-apoptotic effects of DAS might be reduced by ABCB1 or ABCG2 overexpression at clinically relevant concentration, the actual effect of the studied ABC transporters on DAS efficiency depends on their expression levels. The lower expression levels of ABC transporters mediate lower resistance. Considering the fact that expression levels of ABCB1 and ABCG2 transporters are hardly high in clinical samples, their contribution to the overall resistance to DAS is probably low but significant.

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Additional Information:

This research is published in the open access journal BioDiscovery, as part of the special collection “From Drug Discovery to Clinical Trials” dedicated to outputs from the Second Clinical Sciences and Drug Discovery Conference, which took place in July, in Dundee, Scotland.

The aim of BioDiscovery is to provide a platform for scientists in all areas of biology and medicine to promote, share and discuss new ideas and developments. BioDiscovery considers for publication original, high quality research which contributes significantly for the development of the knowledge in biology and medicine. Articles submitted to BioDiscovery benefit from its broad scope and readership, and dedicated media promotion.

Follow BioDiscovery on Twitter @BioDiscoveryJrn

Original Source:

Mlejnek P, Dolezel P, Ruzickova E (2017) Drug resistance of cancer cells is crucially affected by expression levels of ABC-transporters. BioDiscovery 20: e11211. https://doi.org/10.3897/biodiscovery.20.e11211

New frog from the Peruvian Andes is the first amphibian named after Sir David Attenborough

While there are already a number of species named after famous British broadcaster and naturalist Sir David Attenborough, including mammals, reptiles, invertebrates and plants, both extinct and extant, not until now has the host of the BBC Natural History’s Life series been honoured with an amphibian.

A new fleshbelly frog, recently discovered in the Peruvian Andes, is formally described as Pristimantis attenboroughi, while commonly it is to be referred to as the Attenborough’s Rubber Frog. The new species is published in the open-access journal ZooKeys.

Scientists Dr. Edgar Lehr, Illinois Wesleyan University, and Dr. Rudolf von May, University of Michigan, spent two years (2012-2014) surveying montane forests in central Peru, in order to document the local amphibians and reptiles, and evaluate their conservation statuses. Their efforts have been rewarded with several new species of frogs and a new spectacled lizard.

Each of these discoveries, including the Attenborough’s Rubber Frog, prove how beneficial it is to take into account both morphological and the genetic data, while looking for species new to science. For example, the authors report that when they spotted the P. attenboroughi frog for the first time, both of them were sure that they had found a species of another genus.

The Attenborough’s rubber frog is known to inhabit several localities across the Pui Pui Protected Forest, a nature reserve located at elevations between 3400 and 3936 m a.s.l. in central Peru. The adult males reach size of 14.6-19.2 mm in length, while the females are larger measuring between 19.2 and 23.0 mm. Their ground colour ranges from pale to dark gray, or reddish brown to brownish olive with dark gray scattered flecks. Meanwhile, the juveniles are paler (yellowish to reddish brown) with contrasting dark brown flecks and distinct stripes.

Due to the amphibian being known from fewer than ten localities, spread across less than 20,000 km2, the species should be deemed either Vulnerable or Endangered, according to the IUCN Red List Categories and Criteria. However, the authors suggest that the Attenborough’s Rubber frog should be listed as Near Threatened instead, since the Piu Piu forest is formally protected and still largely unknown, so it is likely that there are more additional populations of the new species. On the other hand, factors such as fungal infections, climate change, pollution, and man-made fires continue to be threats for many Andean amphibians even inside protected areas.

“We dedicate this species to Sir David Frederick Attenborough in honor for his educational documentaries on wildlife, especially on amphibians (e.g., Life in Cold Blood, Fabulous Frogs), and for raising awareness about the importance of wildlife conservation,” explain the authors.

In the present study, the scientists note that there are more terrestrial-breeding frogs from the surveyed montane forests that will be described in the near future.

Among the numerous namesakes of Sir David Attenborough to date, there are a rare genus of beautiful flowering plants, a rare butterfly species, commonly known as the Attenborough’s black-eyed satyr, a flightless weevil species, as well as a number of extinct species.

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Original source:

Lehr E, von May R (2017) A new species of terrestrial-breeding frog (Amphibia, Craugastoridae, Pristimantis) from high elevations of the Pui Pui Protected Forest in central Peru. ZooKeys 660: 17-42. https://doi.org/10.3897/zookeys.660.11394

RAINBIO: a mega database improves knowledge on distribution of vascular plants in tropical Africa

Last November, PhytoKeys published an exciting paper on the launch of the first-of-its kind RAINBIO mega database of tropical African vascular plant distributions.

The publication is part of the RAINBIO project (African RAIN forest community dynamics: implications for tropical BIOdiversity conservation and climate change mitigation, http://rainbio.cesab.org) funded by CESAB (CEntre de Synthèse et d’Analyse sur la Biodiversité) of the FRB (Fondation pour la Recherche sur la Biodiversité, France). Making use of the innovative data paper format, offered by most Pensoft journals, the project announced is key product – a state-of-the-art high quality mega database of vascular plant species distribution across tropical Africa.

The RAINBIO mega database is a response to the limited knowledge of plant species distribution patterns when it comes to the tropical vegetation of Africa. Africa’s vegetation is characterised by high levels of species diversity. However, it is now undergoing important shifts in response to the challenges of ongoing climate change and increasing anthropogenic pressures. To better foster conservation and preservation of ecosystems, basic knowledge about plant species distribution is an important prerequisite.

To compile a comprehensive collection of data, RAINBIO merged large publicly available datasets, in combination with smaller private databases, resulting in a mega database containing 609,776 unique georeferenced records allowing the exploration and extraction of distributional data for 22,577 plant species across continental tropical Africa.

After announcing the database with us at the end of last year, the project published a companion research article providing a state-of-the-art synthesis about our understanding of vascular plant distribution across tropical Africa. The paper, published in BMC Biology concludes that botanical exploration of tropical Africa is far from complete, stressing the importance of continued field inventories and herbarium digitization of past collections.

Analysing this unique dataset provides some important insights into African biodiversity. For example, the observed number of tree species for African forests was smaller than those estimated from global tree data, suggesting that a significant number of species are yet to be discovered. The article also contains a comprehensive list of the total number of plant species for 31 countries across tropical Africa.

The data compiled in the RAINBIO database provides a solid basis for a more sustainable management and improved conservation of tropical Africa’s unique flora, and is important for achieving Objective 1 of the Global Strategy for Plant Conservation 2011–2020.

Original Sources:

Dauby G, et al. (2016) RAINBIO: a mega-database of tropical African vascular plants distributions. PhytoKeys 74: 1-18. https://doi.org/10.3897/phytokeys.74.9723

Sosef M S M, et al. (2016) Exploring the floristic diversity of tropical Africa. BMC Biology 15:15. https://doi.org/10.1186/s12915-017-0356-8

Portuguese moth’s mystery solved after 22 years

An unknown moth, collected from Portugal 22 years ago, has finally been named and placed in the tree of life thanks to the efforts of an international team of scientists. The moth was unambiguously placed in the family of geometer moths (Geometridae), commonly known as loopers or inchworms due to the characteristic looping gait of their larvae.

The new species description is published in the open access journal Nota Lepidopterologica, along with a taxonomic review of the genus Ekboarmia, thought to comprise four species in the western Mediterranean area.

The first specimen, a male, was found in 1995 in Lagoa de Santo André, south of Lisbon, near the Atlantic coast. Despite its unique appearance, the specialists did not find enough similarities with any other European species, making its classification impossible. When three females were finally found following an intensive search in 2009, the team of scientists hoped they would find enough evidence to solve the mystery.

“The discovered females had different wing patterns compared to the males, suggesting sexual dimorphism, adding another complexity in the identification. This new species could not have been classified on the basis of external characters alone,” explains Dieter Stüning from Zoologisches Forschungsmuseum Alexander Koenig, Bonn, Germany.

In 2015, two specimens, a male and a female, have been DNA barcoded and recently became targets of detailed morphological examinations. DNA data played an essential role in demonstrating that the male and the female belong to the same species, whereas morphological structures finally provided unambiguous evidence to place the mystery moth in the geometrid genus Ekboarmia. The species name miniaria seemed appropriate to denote its small size. The tiny moth is the smallest in its genus whose other species are externally dissimilar.

Peder Skou from Denmark played a central role in the discovery of the species, tirelessly searching for more material to solve the questions. “Discovery of an undescribed and distinct macromoth from Europe is a rare occasion, because the continent’s fauna is probably the most exhaustively studied in the world,” explains Skou.

Pasi Sihvonen from the Finnish Museum of Natural History concludes: “Virtually nothing is known about the species. Altogether, only 11 specimens have been found between 1995 and 2011. Larvae of related species feed on juniper needles, which might also be the foodplant of the new species. We hope that the richly illustrated publication of the new moth will lead to new discoveries of this mysterious species. More data are needed, for instance, its conservation status cannot be evaluated due to insufficient life history and distribution data.”

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Original source:

Skou P, Stüning D, Sihvonen P (2017) Revision of the West-Mediterranean geometrid genus Ekboarmia, with description of a new species from Portugal (Lepidoptera, Geometridae, Ennominae). Nota Lepidopterologica 40(1): 39-63. https://doi.org/10.3897/nl.40.10440

Shadow-loving insect named after Tuomas Holopainen of Nightwish

Tuomas Holopainen, the multi-talented musician and founder of the symphonic metal band Nightwish, is also a full-blooded nature person. This gave conservation biologist Jukka Salmela of Metsähallitus Parks & Wildlife Finland an idea for the name of a new species he found in Finland. Discovered in eastern Lapland during an insect survey, the fungus gnat was given the scientific name Sciophila holopaineni after Tuomas. The new species is described in the open access Biodiversity Data Journal.

“I am very, very touched. This is the highest honour a nature nerd like me can receive,” Tuomas Holopainen replied after Jukka, who collected and described the fungus gnat, asked him for permission to name the species after him.

The idea for the name came up to Salmela while he was thinking about the habitat and appearance of the species. Then, he recalled Tuomas Holopainen’s interest in the natural sciences.

So far, the new species of fungus gnat has been only known from two locations: the Törmäoja Natura Area in Savukoski, eastern Lapland, and a meadow close to the White Sea, Russian Karelia.

The dark and beautiful gnat thrives in shadowy environments. In Törmäoja, it was caught in a river gulch next to the river source, while hiding under the shelter of the forest. Salmela proposes ‘tuomaanvarjokainen’ as the common Finnish name, inspired by the latest Nightwish album. After all, the themes of the album, Endless Forms Most Beautiful, are evolution and the diversity of nature.

Fungus gnats are flies, which feed on dead wood or fungi. Some of the larvae are predaceous. At current count, there are almost 800 species in Finland and about 1,000 in the Nordic countries. In fact, the Fennoscandia region is one of Europe’s biodiversity hotspots for this group of insects.

The Tuomas Holopainen’s species is only one of the eight new flies described in the study. Among them are the Boletina norokorpii fungus gnat, named after Docent Yrjö Norokorpi and known only from Ylitornio; Phronia reducta, which inhabits Salla and Siberia; and Orfelia boreoalpina found in Törmäoja and the German Alps.

The Parks & Wildlife Finland of Metsähallitus is responsible for the management and species surveys of the State’s nature reserves. The collected data is needed in activities such as assessing the status of biodiversity, the protection of species, and planning the management and use of the reserves. Insects are as good an indicator of the state of the natural environment as better-known vertebrates or plants. The diversity of insect species forms part of natural biodiversity and is necessary to human well-being.

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Original source:

Salmela J, Kolcsár L (2017) New and poorly known Palaearctic fungus gnats (Diptera, Sciaroidea). Biodiversity Data Journal 5: e11760. https://doi.org/10.3897/BDJ.5.e11760

Gehry’s Biodiversity Museum – favorite attraction for the butterflies and moths in Panama

Ahead of Gehry’s Biodiversity Museum‘s opening in October 2014, PhD candidate Patricia Esther Corro Chang, Universidad de Panama, studied the butterflies and moths which had been attracted by the bright colours of the walls and which were visiting the grounds of the tourist site.

The resulting checklist, published in the open access journal Biodiversity Data Journal, aims to both evaluate the biodiversity and encourage the preservation and development of the Amador Causeway (Calzada de Amador) and the four Causeway Islands. The name of the islands derives from their being linked to each other and the mainland via a causeway made of rocks excavated during the construction of the Panama Canal.

The researcher reports a total of six butterfly and eight moth families, identified from the 326 specimens collected over the course of 10 months from the botanical garden of the museum and adjacent areas. They represent a total of 52 genera and 60 species.

Interestingly, the eye-catching bright colours of the walls of the museum seem to play an important role for the insect fauna of the area. Not only are numerous butterflies and moths being attracted to the site, but they also express curious behaviour. On various occasions, for example, a species of skipper butterfly was seen to show a clear preference for yellowish surfaces. In their turn, a number of butterfly predators, such as jumping spiders, are also frequenting the walls.

The article in the journal provides knowledge of the butterfly and moth fauna at the mainly vegetated study area, located on a narrow strip of water distant from the city of Panama.

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Original source:

Corro-Chang P (2017) Behavioural notes and attraction on Lepidoptera around the Gehry’s Biodiversity Museum (Causeway, Calzada de Amador, Panamá, República de Panamá). Biodiversity Data Journal 5: e11410. https://doi.org/10.3897/BDJ.5.e11410

Bird spiders detectives: The solution to a 200-year-old hairy mystery

Three species and three genera of birdeater spiders are described as new to science in a paper recently published in the open access journal ZooKeys. In their study, the Brazilian spider experts, Drs. Caroline Fukushima and Rogério Bertani, Laboratory of Ecology and Evolution, Instituto Butantan, report the diversity of the oldest tarantula genus (Avicularia), whose name derives from a famous 18th-century illustration depicting a bird caught by a spider.

Even though these harmless tarantulas have long been a favourite exotic pet around the world, their identity has remained problematic ever since the first species was described back in 1758 by the “father of modern taxonomy”, Carl Linnaeus.

“He described the species based on a hodgepodge of spiders,” explain the authors. “Over the next centuries, other species with completely different characteristics were called Avicularia creating a huge mess.” As a result, basic questions, such as the characteristic traits of the genus, the number of its species and their localities, have been left unanswered.

To address the confusion, the team studied both newly collected specimens and also specimens from around the world which had previously been deposited in museum collections. Thus, they concluded that, instead of the 49 species previously assigned to the problematic genus, there are in fact only 12, including three new to science.

One of the new species, Avicularia merianae, is named after Maria Sybilla Merian (1647-1717), a pioneering scientist and a remarkable artist who made the famous illustration of a spider eating a bird. In fact, it was her work that gave birth to the popular name used for a whole group of spiders, also known as birdeaters or bird spiders.

Meanwhile, the name of the new genus Ybyrapora, which occurs in the Brazilian Atlantic rainforest, translates to “those that live in trees” from the indigenous local language Tupi. It refers to the arboreal habitat of these species. The other two tarantula genera live exclusively on the Caribbean Islands.

“People think all biologists are like Indiana Jones, with their daily lives full of adventures in the wild. But most of the time, they are much more like Sherlock Holmes – sitting on a chair, collecting and analysing clues (specimens and scientific papers) and then using logical reasoning to solve Nature’s mysteries,” comments Dr. Caroline Fukushima.

“We, taxonomists, are ‘wildlife detectives’ who play an essential role not only in biology and conservation. Our work can also become the grounds for new technologies, medicines and ideas that could solve a variety of problems,” she adds.

“We are delighted to have finally closed one of the oldest unsolved cases,” the authors conclude.

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Original source:

Fukushima CS, Bertani R (2017) Taxonomic revision and cladistic analysis of Avicularia Lamarck, 1818 (Araneae, Theraphosidae, Aviculariinae) with description of three new aviculariine genera. ZooKeys 659: 1-185. https://doi.org/10.3897/zookeys.659.10717

Saving the Underworld: Clarifying the subterranean fauna classification for improved conservation

Inevitably, many habitats, including the particularly vulnerable subterranean ones, will continue being erased from our planet as a result of human activities and interests. The challenge is to protect the ones that are the sole habitats to certain organisms, so that their species are safe from extinction. Hence, it is essential that the distribution of every each one of them is clearly defined.

Brazilian scientists Prof. Eleonora Trajano, Universidade Federal de São Carlos, and Prof. Dr. Marcelo Rodrigues de Carvalho, Universidade de São Paulo, discuss the current classification system, its application and complexities in a paper published in the open access Subterranean Biology.

Nowadays, there are three categories of subterranean fauna accepted. Troglobites live exclusively underground and are usually characterised with reduced or lacking eyes and pale or transparent colors; troglophiles may live both in caves and on the surface, with individuals commuting between these habitats and promoting genetic interchange between subterranean and surface populations; trogloxenes use caves regularly, but must leave them periodically in order to complete their life cycle.

Throughout the years, many alterations and subdivisions have been applied to the classification used when determining whether a cave organism belongs exclusively to the subterranean habitat, or not, before concluding these three groups, also known as the Schiner-Racovitza system. It is important to separate them properly, since the destruction of a habitat to an endemic troglobite, for instance, would immediately wipe out its whole species, as it would be impossible for the animals to move away.

However, many historic publications do not feature enough details about the described species’ distribution, nor identification of the used classification, so that the information is unreliable. Furthermore, there have been times, when people have been even afraid to survey the underground habitats, led by beliefs and associations linking caves to the “World of the Dead”.

In their paper, the authors conclude that the only way to define the species status of subterranean organisms with certainty is to study each species’ dynamics over a period of at least three years, since animals may migrate on a seasonal and/or non-seasonal basis. Also, scientists need to study thoroughly the area outside the surveyed cave, while testing for sampling sufficiency at all times.

“When employing classifications of subterranean organisms, especially for conservation purposes, these conditions should be checked for reliability of the status attributed to them,” say the authors. “Misplacing these organisms within the Schiner-Racovitza categories impairs the efficiency of such policies.”

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Original source:

Trajano E, Carvalho MR (2017) Towards a biologically meaningful classification of subterranean organisms: a critical analysis of the Schiner-Racovitza system from a historical perspective, difficulties of its application and implications for conservation. Subterranean Biology 22: 1-26. https://doi.org/10.3897/subtbiol.22.9759

Bee species with little known nesting-behavior observed to use plastic instead of leaves

Little is known about the nesting activities of some lineages of megachiline bees. Dr. Sarah Gess, affiliated with both Albany Museum and Rhodes University, South Africa, and Peter Roosenschoon, Conservation Officer at the Dubai Desert Conservation Reserve, United Arab Emirates, made use of their earlier observations gathered during a survey on flower visitation in the spring of 2015, to fill some gaps in the knowledge of of three species from such lineages.

Among their findings, published in the open access Journal of Hymenoptera Research, is a curious instance of a bee attempting to build brood cells using green pieces of plastic. Having examined two nests of the leafcutter bee species Megachile (Eurymella) patellimana, they report that one of the females nested in burrows in compacted sandy ground beneath a plant, and the other – in the banks of an irrigation furrow.

However, while the former was seen carrying a freshly cut leaf, the latter seemed to have discovered a curious substitute in the form of green plastic. Later on, upon checking the nest, the researchers found that the phenomenon they had observed was no isolated incident – at least six identical pieces of narrow, tough, green plastic were grouped together in an apparent attempt to construct a cell. It turns out that the bee had been deliberately cutting off approximately 10-milimetre-long pieces with its large and strong toothed mandibles, before bringing them back to the nest.

“Although perhaps incidentally collected, the novel use of plastics in the nests of bees could reflect ecologically adaptive traits necessary for survival in an increasingly human-dominated environment,” the authors quote an earlier study.

The two studied mason bee species (Megachile (Maximegachile) maxillosa and Pseudoheriades grandiceps) were seen to construct their nests using a mixture of resin and sand in pre-existing cavities, such as trap-nests, above the ground. The researchers note that resin is a common nest-building material among numerous species of mason bees, also known as resin bees. Previously, it has been suggested that apart from making the nest waterproof, the plant secretions may contain substances that fend off parasites.

The authors’ earlier paper exploring the flower visitation by bees and wasps in the Dubai Desert Conservation Reserve is also published in the open-access Journal of Hymenoptera Research.

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Original source:

Gess SK, Roosenschoon PA (2017) Notes on the nesting of three species of Megachilinae in the Dubai Desert Conservation Reserve, UAE. Journal of Hymenoptera Research 54: 43-56. https://doi.org/10.3897/jhr.54.11290

New species of parasitic wasp discovered in the eggs of leaf-rolling weevils in Africa

A new species of parasitic wasp has been obtained from the eggs of weevils, associated with bushwillows, collected and identified by Dr. Silvano Biondi. Given the tiny insect from northeastern Gabon is the first record of its genus for West-Central Africa, the researchers Dr. Stefania Laudonia and Dr. Gennaro Viggiani, both affiliated with Italy’s University of Naples Federico II, decided to celebrate it by assigning the species a name that refers to the continent. Their team has published the findings in the open access journal ZooKeys.

Named Poropoea africana, the new species belongs to a large worldwide group of wasps well-known as egg parasitoids of leaf-rolling weevils. Using characteristically long ovipositors, they lay their own eggs in the eggs of the hosts, found in cigar-like rolls.

The new wasp measures less than 2 mm. It can be distinguished from related species by a number of characters, including the structure of the antennae, and the front and hind legs, which are more robust than the middle ones. The latter, which is a unique trait for the genus, seems to be an adaptation to host parasitisation, where the modified legs likely support the body and improve the propulsive efficiency of the ovipositor.

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Original source:

Laudonia S, Viggiani G, Biondi S (2017) A new species of Poropoea Foerster from Africa (Hymenoptera, Chalcidoidea, Trichogrammatidae). ZooKeys 658: 81-87. https://doi.org/10.3897/zookeys.658.11501