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Seufferheld M.J.,University of Illinois at Urbana - Champaign | Kim K.M.,University of Illinois at Urbana - Champaign | Kim K.M.,Korea Research Institute of Bioscience and Biotechnology | Whitfield J.,University of Illinois at Urbana - Champaign | And 2 more authors.
Biology Direct | Year: 2011

Background: Volutin granules appear to be universally distributed and are morphologically and chemically identical to acidocalcisomes, which are electron-dense granular organelles rich in calcium and phosphate, whose functions include storage of phosphorus and various metal ions, metabolism of polyphosphate, maintenance of intracellular pH, osmoregulation and calcium homeostasis. Prokaryotes are thought to differ from eukaryotes in that they lack membrane-bounded organelles. However, it has been demonstrated that as in acidocalcisomes, the calcium and polyphosphate-rich intracellular "volutin granules (polyphosphate bodies)" in two bacterial species, Agrobacterium tumefaciens, and Rhodospirillum rubrum, are membrane bound and that the vacuolar proton-translocating pyrophosphatases (V-H+PPases) are present in their surrounding membranes. Volutin granules and acidocalcisomes have been found in organisms as diverse as bacteria and humans.Results: Here, we show volutin granules also occur in Archaea and are, therefore, present in the three superkingdoms of life (Archaea, Bacteria and Eukarya). Molecular analyses of V-H+PPase pumps, which acidify the acidocalcisome lumen and are diagnostic proteins of the organelle, also reveal the presence of this enzyme in all three superkingdoms suggesting it is ancient and universal. Since V-H+PPase sequences contained limited phylogenetic signal to fully resolve the ancestral nodes of the tree, we investigated the divergence of protein domains in the V-H+PPase molecules. Using Protein family (Pfam) database, we found a domain in the protein, PF03030. The domain is shared by 31 species in Eukarya, 231 in Bacteria, and 17 in Archaea. The universal distribution of the V-H+PPase PF03030 domain, which is associated with the V-H+PPase function, suggests the domain and the enzyme were already present in the Last Universal Common Ancestor (LUCA).Conclusion: The importance of the V-H+PPase function and the evolutionary dynamics of these domains support the early origin of the acidocalcisome organelle. In particular, the universality of volutin granules and presence of a functional V-H+PPase domain in the three superkingdoms of life reveals that the acidocalcisomes may have appeared earlier than the divergence of the superkingdoms. This result is remarkable and highlights the possibility that a high degree of cellular compartmentalization could already have been present in the LUCA.Reviewers: This article was reviewed by Anthony Poole, Lakshminarayan Iyer and Daniel Kahn. © 2011 Seufferheld et al; licensee BioMed Central Ltd.


News Article | December 21, 2016
Site: phys.org

And when those adventurers leave home, they travel an average of six miles - and as far as almost nine miles - to new breeding sites, a new study has found. That's a long haul on four squatty legs. The scientists who unlocked this evolutionarily important information got there by cross-referencing genetic details from salamanders in various Ohio wetlands with the distance the animals would walk on a treadmill before tiring out. The research, published online this month in the journal Functional Ecology, is the work of scientists at The Ohio State University who want to better understand how and where salamanders procreate and how that fits into work to preserve the animals, including land conservation efforts. It is a mystery what prompts a salamander to cross rocks, fields, streams and roads to mate and, in the process, mix up the genetics of another salamander outpost far from home, said lead author Robert Denton. "It has to be incredibly intimidating for these tiny salamanders. They could get eaten by a crow or a raccoon. They could dry out," said Denton, a presidential research fellow in Ohio State's Department of Evolution, Ecology and Organismal Biology. "This is the first study to connect physiological factors - particularly how fast they get tired of walking - with genetics showing animal movement in the field." Understanding these connections is critical to predicting how environmental and other changes can harm species, Denton said. Dispersal - leaving the birthplace for a new habitat - is a key element of keeping a species genetically healthy, he said. Animal travel for breeding is a complex area of research, he said. There are a lot of factors to consider, including how they decide to move, why only certain animals hit the road and how they actually complete the journey - in a series of shorter trips or all at once, for instance. And when it comes to salamanders, things get particularly tricky. "They live these really mysterious lives - we only see them out for a couple days in the spring. They spend most of their time just hiding," Denton said. Furthermore, they have fragile skin that prevents insertion of any kind of tracking device. To shed light on the mystery, the researchers looked at genetic diversity and endurance in two types of mole salamanders (part of the Ambystoma genus.) One type is all-female and reproduces by cloning and sometimes borrowing sperm that males leave behind on twigs and leaves. The other type mates in a more traditional manner. The "sexual" salamanders walked on the treadmill an average of four times longer before reaching fatigue than their all-female counterparts. Denton and his colleagues measured fatigue as the point where the salamander didn't "right" itself within a few seconds when removed from the treadmill and placed on its back. Prompting a salamander to walk on a miniature treadmill isn't much of a challenge, Denton said. A small pinch of the tail or poke in the behind, and they're off at a slow, steady pace. The treadmill - borrowed from another research team - is outfitted with plastic walls that ensure the animals don't take a spill off the side, as they tend to not walk a straight line. "They're like endurance athletes. Some of them could walk for two-plus hours straight without tiring themselves," Denton said. "That's like a person lightly jogging for 75 miles before wearing out." Genetic information collected in the wetlands lined up with the treadmill tests. Sexual salamanders were found approximately twice as far from their birthplace as the all-female cloning animals. The DNA analysis included testing of tissue samples from all known breeding wetlands in a salamander-rich area of rural Ohio. The researchers collected samples from the tail tips of 445 salamanders. Differences between the all-female and sexual salamanders could have multiple explanations, Denton said. "Maybe the best explanation for why sexual salamanders travel so far is because they have to: On a large landscape with few places to breed, the animals that can cross that distance are the ones that survive and reproduce," he said. "Perhaps the more interesting question is why the all-female salamanders don't go very far, and we think that has to do with the physiological costs of not having sex. Essentially, not mixing up your genomic material often enough likely causes some problems for genes that you need to make energy." In a given wetland mating area, most of the DNA samples looked alike. But there were outliers. "We looked for the ones that stood out like sore thumbs," Denton said. About 4 percent of salamanders were out of sync genetically, and could be linked to other wetlands where they were born, Denton said. That information allowed him and his colleagues to map the distances some of the animals traveled to mate. "It was surprising to us that they go really long distances - four, five, six miles - from home," Denton said.


News Article | December 21, 2016
Site: www.eurekalert.org

COLUMBUS, Ohio - Most salamanders are homebodies when it comes to mating. But some of the beasts hit the road, traversing miles of rugged terrain unfit for an amphibian in pursuit of a partner from a far-away wetland. And when those adventurers leave home, they travel an average of six miles - and as far as almost nine miles - to new breeding sites, a new study has found. That's a long haul on four squatty legs. The scientists who unlocked this evolutionarily important information got there by cross-referencing genetic details from salamanders in various Ohio wetlands with the distance the animals would walk on a treadmill before tiring out. The research, published online this month in the journal Functional Ecology, is the work of scientists at The Ohio State University who want to better understand how and where salamanders procreate and how that fits into work to preserve the animals, including land conservation efforts. It is a mystery what prompts a salamander to cross rocks, fields, streams and roads to mate and, in the process, mix up the genetics of another salamander outpost far from home, said lead author Robert Denton. "It has to be incredibly intimidating for these tiny salamanders. They could get eaten by a crow or a raccoon. They could dry out," said Denton, a presidential research fellow in Ohio State's Department of Evolution, Ecology and Organismal Biology. "This is the first study to connect physiological factors - particularly how fast they get tired of walking - with genetics showing animal movement in the field." Understanding these connections is critical to predicting how environmental and other changes can harm species, Denton said. Dispersal - leaving the birthplace for a new habitat - is a key element of keeping a species genetically healthy, he said. Animal travel for breeding is a complex area of research, he said. There are a lot of factors to consider, including how they decide to move, why only certain animals hit the road and how they actually complete the journey - in a series of shorter trips or all at once, for instance. And when it comes to salamanders, things get particularly tricky. "They live these really mysterious lives - we only see them out for a couple days in the spring. They spend most of their time just hiding," Denton said. Furthermore, they have fragile skin that prevents insertion of any kind of tracking device. To shed light on the mystery, the researchers looked at genetic diversity and endurance in two types of mole salamanders (part of the Ambystoma genus.) One type is all-female and reproduces by cloning and sometimes borrowing sperm that males leave behind on twigs and leaves. The other type mates in a more traditional manner. The "sexual" salamanders walked on the treadmill an average of four times longer before reaching fatigue than their all-female counterparts. Denton and his colleagues measured fatigue as the point where the salamander didn't "right" itself within a few seconds when removed from the treadmill and placed on its back. Prompting a salamander to walk on a miniature treadmill isn't much of a challenge, Denton said. A small pinch of the tail or poke in the behind, and they're off at a slow, steady pace. The treadmill - borrowed from another research team - is outfitted with plastic walls that ensure the animals don't take a spill off the side, as they tend to not walk a straight line. "They're like endurance athletes. Some of them could walk for two-plus hours straight without tiring themselves," Denton said. "That's like a person lightly jogging for 75 miles before wearing out." Genetic information collected in the wetlands lined up with the treadmill tests. Sexual salamanders were found approximately twice as far from their birthplace as the all-female cloning animals. The DNA analysis included testing of tissue samples from all known breeding wetlands in a salamander-rich area of rural Ohio. The researchers collected samples from the tail tips of 445 salamanders. Differences between the all-female and sexual salamanders could have multiple explanations, Denton said. "Maybe the best explanation for why sexual salamanders travel so far is because they have to: On a large landscape with few places to breed, the animals that can cross that distance are the ones that survive and reproduce," he said. "Perhaps the more interesting question is why the all-female salamanders don't go very far, and we think that has to do with the physiological costs of not having sex. Essentially, not mixing up your genomic material often enough likely causes some problems for genes that you need to make energy." In a given wetland mating area, most of the DNA samples looked alike. But there were outliers. "We looked for the ones that stood out like sore thumbs," Denton said. About 4 percent of salamanders were out of sync genetically, and could be linked to other wetlands where they were born, Denton said. That information allowed him and his colleagues to map the distances some of the animals traveled to mate. "It was surprising to us that they go really long distances - four, five, six miles - from home," Denton said. The study was supported by the Ohio Biodiversity Conservation Partnership, the American Society of Ichthyologists and Herpetologists and a SciFund crowdfunding effort by Denton. Other researchers who worked on the study were Ohio State's H. Lisle Gibbs and Katherine Greenwald of Eastern Michigan University.


Harder J.D.,Ecology and Organismal Biology | Kotheimer J.K.,Ecology and Organismal Biology | Hamilton I.M.,Ecology and Organismal Biology | Hamilton I.M.,Ohio State University
Northeastern Naturalist | Year: 2014

The goal of this study was to obtain information on diversity, abundance, and distribution of non-volant small mammals in 4 major habitat types in each of 5 regions of Ohio. We trapped in 31 study areas, representing 39 counties, for 3 consecutive nights for a total of 38,400 trap nights. We established eight 100-m transects (each with 10 live traps, 20 snap traps, and 20 pitfall traps) per study area in woodland, oldfield, grassland-pasture, or restored prairie-wetland habitats. We captured fourteen species of small mammals (shrews and rodents <100 g in body mass), but 97% of the 2150 captured consisted of just 4 species: Microtus pennsylvanicus (Meadow Vole; 31%), Peromyscus leucopus (White-footed Mouse; 29%), Blarina brevicauda (Short-tailed Shrew; 21%), and Sorex cinereus (Masked Shrew; 16%). Regional differences in abundance of small mammals (captures/100 trap nights) and species diversity (H') were not significant (P > 0.05). Seven species of interest were captured in low numbers (<10) and 2 others, Reithrodontomys humulis (Eastern Harvest Mouse) and Myodes gapperi (Red-backed Vole), were not captured in the course of the 2-year study. © AlphaMed Press 2014.


A new species of crayfish, Cambarus (Tubericambarus) stockeri, is described from northern Georgia and southern Tennessee within the Ridge and Valley Physiographic Province of North America. Of the recognized members of the subgenus, it is the most physically divergent form discovered to date. It is easily distinguished from other recognized members of the subgenus, and all other members of the genus Cambarus Erichson 1846, by the extensive tuberculation of the chelae. Cambarus (T.) stockeri has tubercles over most of the dorsal and ventral chelae surface, a character state common in members of Procambarus Ortmann, 1905b. This new species was frequently found in association with Cambarus (T.) acanthura, Hobbs, 1981 and Cambarus (Depressicambarus) cymatilis, Hobbs, 1970 and shares a close zoogeographic association with the latter species. © Biological Society of Washington.

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