No, this isn't Jurassic Park

It is the youngest nodosaur ever discovered

No, this isn't Jurassic Park. Researchers at the Johns Hopkins University School of Medicine with help from an amateur fossil hunter in College Park, Md., have described the fossil of an armored dinosaur hatchling. It is the youngest nodosaur ever discovered, and a founder of a new genus and species that lived approximately 110 million years ago during the Early Cretaceous Era. Nodosaurs have been found in diverse locations worldwide, but they've rarely been found in the United States. The findings are published in the September 9 issue of the Journal of Paleontology. 

"Now we can learn about the development of limbs and the development of skulls early on in a dinosaur's life," says David Weishampel, Ph.D., a professor of anatomy at the Johns Hopkins University School of Medicine. "The very small size also reveals that there was a nearby nesting area or rookery, since it couldn't have wandered far from where it hatched. We have the opportunity to find out about dinosaur parenting and reproductive biology, as well as more about the lives of Maryland dinosaurs in general."

The fossil was discovered in 1997 by Ray Stanford, a dinosaur tracker who often spent time looking for fossils close to his home; this time he was searching a creek bed after an extensive flood.

Stanford identified it as a nodosaur and called Weishampel, a paleontologist and expert in dinosaur systematics. Weishampel and his colleagues established the fossil's identity as a nodosaur by identifying a distinctive pattern of bumps and grooves on the skull. They then did a computer analysis of the skull shape, comparing its proportions to those of ten skulls from different species of ankylosaurs, the group that contains nodosaurs. They found that this dinosaur was closely related to some of the nodosaur species, although it had a shorter snout overall than the others. Comparative measurements enabled them to designate a new species, Propanoplosaurus marylandicus. In addition to being the youngest nodosaur ever found, it is the first hatchling of any dinosaur species ever recovered in the eastern United States, says Weishampel.

The area had originally been a flood plain, where Weishampel says that the dinosaur originally drowned. Cleaning the fossil revealed a hatchling nodosaur on its back, much of its body imprinted along with the top of its skull. Weishampel determined the dinosaur's age at time of death by analyzing the degree of development and articulation capability of the ends of the bones, as well as deducing whether the bones themselves were porous, as young bones would not be fully solid. 

Size was also a clue: the body in the tiny fossil was only 13 cm long, just shorter than the length of a dollar bill. Adult nodosaurs are estimated to have been 20 to 30 feet long. Weishampel also used the position and quality of the fossil to deduce the dinosaur's method of death and preservation: drowning, and getting buried by sediment in the stream. Egg shells have never been found preserved in the vicinity, and by the layout of the bones and the size of some very small nodosaur footprints found nearby, led Weishampel to believe that the dinosaur was a hatchling, rather than an embryo, because it was able to walk independently.

"We didn't know much about hatchling nodosaurs at all prior to this discovery," says Weishampel. "And this is certainly enough to motivate more searches for dinosaurs in Maryland, along with more analysis of Maryland dinosaurs." Source: www.biologynews.net.

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Scientists at the Max Planck Institute of Developmental Biology in Germany

Epigenetic changes don't last

Jean-Baptiste Lamarck would have been delighted: geneticists no longer dismiss out of hand his belief that acquired traits can be passed on to offspring. When Darwin published his book on evolution, Lamarck's theory of transformation went onto the ash heap of history. But in the last decade, we have learned that the environment can after all leave traces in the genomes of animals and plants, in form of so-called epigenetic modifications. Scientists at the Max Planck Institute of Developmental Biology in Germany have now produced the first comprehensive inventory of spontaneous epigenetic changes. Using Arabidopsis, the workhorse of modern plant genetics, the researchers determined how often and where in the genome epigenetic modifications occur – and how often they disappear again. They found that epigenetic changes are many orders of magnitude more frequent than conventional DNA mutations, but also often short lived. They are therefore probably much less important for long-term evolution than previously thought.

The team around Detlef Weigel, director of the Department for Molecular Biology, focused on one of the most important epigenetic marks, methylation of DNA. Tiny chemical building blocks, methyl groups, are thereby attached to individual letters of the DNA, mostly to cytosines. The genetic information itself in form of the four different letters or nucleotides that make up the genetic code remains unchanged in this process. To determine the rate and distribution of methylation changes in the genome, the German biologists looked at ten Arabidopsis lines. These lines came from the same stock, but had been propagated independently for 30 generations by self-fertilization. In the genome of the last generation the scientists then searched for differences in the methylation pattern in comparison to the common ancestor. They produced for each individual a complete map of methylated cytosines in the genome, the so-called methylome.

"For each line, we were able to look at about 14 million cytosines," said Claude Becker, a member of the Tübingen team. On average, every plant had almost 3 million methylated cytosines. The vast majority of these were the same in all lines, but about 6 percent had changed since the lines had become separated. At these positions, at least one of the individuals was different, with either methylation gained or lost relative to the ancestor. Each of the lines had about 30,000 such epimutations, which was 1,000 times more than DNA mutations.

With 30,000 epimutations after 30 generations, the geneticists had expected that 1,000 epimutations occurred in each generation. When they directly compared parents and their immediate offspring, they were surprised to find that the epimutation rate was three to four times as high. The scientists concluded that many epimutations are apparently not stable and return to their original state after a few generations. Thus, averaging the mutation rate over many generations is misleading. Becker's colleague Jörg Hagmann therefore cautions not to overestimate the importance of DNA methylation during evolution: "Our experiments show that methylation changes are often reversible". In other words: New epimutations are often not maintained over the long term. "Only when selection wins out over reversion can these epimutations affect evolution," says Hagmann. A new epimutation thus must have a strong evolutionary advantage so that it can become established before being lost again. Because reverse mutations do not necessarily happen in the next generation, it is still possible that epigenetic differences contribute to inheritance of traits between parents and their children or grandparents and their grandchildren.
Another difference to ordinary mutations is that epimutations do not occur randomly, but often at the same places in the genome. While genes were disproportionately often affected, methylation of mobile DNA elements, transposons, was very stable. This appears to make sense, since it was already known that artificially induced loss of methylation has a much greater effect on the activity of transposons than of regular genes.  

More important than the state of individual cytosines is probably the methylation of larger segments of the genome. "In each plant we found only about 30 such regions in which they differed from the other lines," explains Becker. Hagmann adds: "Such whole-sale epigenetic changes appear to be as rare as true DNA sequence mutations". These differences can nevertheless appear very rapidly. The biologists discovered one region that first lost its methyl groups, only to become completely remethylated in the next generation.
What makes epigenetics interesting for human health is the fact that some epigenetic changes can be triggered by external factors. There is evidence that nutrition or the bond between children and their parents can leave traces in the genome that can be passed on to the next generation. The limited stability of DNA methylation implies, however, that such differences do not necessarily last forever, which is probably not a bad idea because a famine might not last forever. It also means that altered DNA methylation often cannot become subject to natural selection.
The results of the Max Planck scientists demonstrate that epigenetic differences can also arise spontaneously, without drastic changes in the environment. After all, the growth conditions in the green house, where each of the 10 lines was propagated, were constant. This opens the door to further speculation. "We suspect that the epimutation increase is higher and more variable when plants grow in nature, where they are stressed all the time", says Becker. If this were paralleled by an even higher reversion rate, then the importance of epigenetics for long-term evolution would be even lower.

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The newest way to know the number of gene and protein expression simultaneously

The newest way

Researchers have discovered a method for simultaneously visualizing gene number and protein expression in individual cells. The fluorescence microscopy technique could permit a detailed analysis of the relationship between gene status and expression of the corresponding protein in cells and tissues, and bring a clearer understanding of cancer and other complex diseases, according to researchers who led the study.

The new technique is called the fluorescent in situ gene protein assay. It combines traditional fluorescent in situ hybridization (FISH) with the in situ proximity ligation assay, which is capable of resolving individual protein molecules.

"To my knowledge, this is the first technique that allows us to concurrently address gene activity and corresponding protein expression in the same cells," says co-principal investigator Dr. Arnab Chakravarti, chair and professor of radiation oncology and co-director of the Brain Tumor Program at the Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC - James).

"The ability to resolve gene and protein-expression changes across a tumor could help us understand what drives tumor behavior overall," Chakravarti says

The new assay is described in the August issue of the journal Neuro-Oncology. For this study, principal investigator Dr. Markus Bredel, an associate professor at the University of Alabama Birmingham, and an adjunct associate professor radiation oncology at the OSUCCC – James, along with Chakravarti and their collaborators first assayed fixed human glioblastoma tumor cells, then paraffin-embedded human glioblastoma tissue. In both cases, the researchers assayed for overexpression of a mutant form of the epidermal growth factor receptor gene, EGFRvIII, and for levels of its truncated protein in glioblastoma.

"This method has potential to perform a detailed analysis of the relationship between cancer gene status and corresponding protein expression in cells and tissues," Bredel says. "We demonstrate that the fluorescent in situ gene protein assay methodology is capable of resolving cancer gene and protein patterns simultaneously on a cell-by-cell basis, which is particularly important in heterogeneous diseases such cancers."

The implications of the assay include the following:

• It is particular relevant to cancer research due to the role of epigenetic and posttranscriptional regulation.
• The ability to correlate gene and protein information in the same cells might increase the reliability of biomarker screens.
• It might aid in therapeutic decision making when screening for only the gene or the protein yields indeterminate results.
• It can be applied to gene-transfection studies that use 'knock-in' models to study the effects of gene number on protein expression.

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Three new species of bat found

Indonesia--Three new species of bat found in tropical forests south of Indochina. One bat species that are found named Satan, and has the scientific name Murina Beelzebub. This type of bat is only found in Vietnam.

"We chose the name of Beelzebub as cruel black owned by this new species, as well as behavioral protection that looks fierce when encountered in the field," said awkward Csorba, Hungarian National History researcher, as quoted by Wired, Friday (09/02/2011) .

The discovery of a new kind of bat was the result of collaboration between biologists and conservation experts from the Hungarian Natural History Museum and the Flora and Fauna International. The discovery, published in the August issue of the Journal of Mammalogy 2011.

Paul Racey, a bat expert and the Vice Chairman of Flora Fauna International said mammal with a bat represents the most variation in Southeast Asia. Number of bat species is estimated to double the number found at this time based on genetic research.

Devil bats and two other new types found included in the tube-nosed bat. The bat's life depends entirely on the existence of tropical forests. They are now threatened by forest destruction activities.

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