lineage

Critical role in programmed cell death identified

...em, Conradt explained, with a well documented cell lineage that facilitates genetic manipulation. Their cell death machinery is simple, with one component for each of the different factors involved in the central cell killing apparatus. Mammals on the other hand have multiple components or families of protei...

UCSD team discovers specialized, rare heart stem cells in newborns

...d into the patient. Furthermore, the developmental lineage marker which identifies undifferentiated cardiogenic precursors suggests the feasibility of isolating isl1+ cardiac progenitors from mouse and human embryonic stem cell systems during cardiogenesis." "We think that these cells normally play an impor...

Fox Chase study shows that weakened T-cell receptor signals change T-cell lineage

...gesting a flexible new model for commitment to one lineage or another. The first, most basic career choice m...cells utilize distinct types of TCR complexes. One lineage employs pairs of TCR proteins termed alpha-beta while the other uses the TCR gamma-delta pair of pro...

Ancient DNA helps clarify the origins of two extinct New World horse species

...erican horses were thought to stem from a very old lineage of fossil forms in North America," Cooper says. "And instead, our data show that they probably diverged and moved into South America around three million years ago, during the great biotic interchange that occurred when the Panama Isthmus was establi...

Fungus-farming termites descend from an African rain forest Eve

...e occurred in which termites domesticated a single lineage of fungi, represented today by the genus Termitomyces, a white rot fungus. These fungi are some of the few organisms that can digest the plant component lignin. Within the termite colonies, which can grow very large, the fungus grows on a special str...

International Team Determines Geographic Origin of Leprosy

...-letter code. Scientists can use SNPs to trace the lineage of an organism, in this case M. leprae, and to develop a picture of how leprosy spread from its point of origin. The team looked for SNPs in 171 clinical specimens of M. leprae taken from people infected with the bacterium. The specimens came from 21...

'Punctuated' evolution in the human genome

...tion. During the divergence of the human/great-ape lineage from the Old World monkey lineage, the genome may have been particularly permissive to segmental duplication events. The scientists speculate that the molecular driving forces behind this "punctuated" duplicative activity may have been changes in tra...

Neanderthal teeth grew no faster than comparable modern humans'

...from about 150,000 to 30,000 years ago until their lineage failed for as-yet unknown reasons. Most researchers have argued that their life in extremely harsh, Ice Age-like environments, coupled with their limited technological skills, ultimately led to their demise. In a study published last year in the jo...

The roots of civilization trace back to ... roots

About five to seven million years ago, when the lineage of humans and chimpanzees split, edible root plants similar to rutabagas and turnips may have been one of the reasons. According to research by anthropologists Greg Laden of the University of Minnesota and Richard Wrangham of Harvard University, the ...

“Hitchhiking?Viruses as Cancer Drug Delivery System

About five to seven million years ago, when the lineage of humans and chimpanzees split, edible root plants similar to rutabagas and turnips may have been one of the reasons. According to research by anthropologists Greg Laden of the University of Minnesota and Richard Wrangham of Harvard University, the ...

Skull study sheds light on dinosaur diversity

...ra. New discoveries, however, are showing that one lineage of sauropods diversified at the end of the dinosau...of the dinosaur era, were really the only sauropod lineage that flourished. All the others went extinct," said Wilson, an assistant professor of geological sci...

New technology shows our ancestors ate…everything!

...been a dream of many researchers interested in our lineage to obtain this kind of information," continued Teaford. "And the computer software is phenomenal, the heart and soul of this project. We now have a reliable technology to quickly and accurately measure such surfaces." Teaford said future applications...

Human brain is still evolving

... of accelerated evolution along the entire primate lineage leading to humans, for the entire thirty to thirty...rred in Microcephalin and ASPM in the evolutionary lineage leading to humans, Lahn and his colleagues took the following approach: They determined the DNA sequ...

Picky female frogs drive evolution of new species in less than 8,000 years

... contact region where a population of the southern lineage had become isolated from the rest of its lineage and had developed a preference for certain male calls. The male frog call in this population has div...

Extinct giant deer's descendant found in UK

...erably since its prehistoric origins. Although its lineage can be seen in the antlers - the fallow deer has the same flattened antlers that the giant deer was renowned for - in size, the modern day deer is comparatively small. The giant deer (or Megaloceros giganteus - meaning gigantic antlers) lived from ...

Study Holds Promise For New Way To Fight HIV

...erably since its prehistoric origins. Although its lineage can be seen in the antlers - the fallow deer has the same flattened antlers that the giant deer was renowned for - in size, the modern day deer is comparatively small. The giant deer (or Megaloceros giganteus - meaning gigantic antlers) lived from ...

Ancient anthropoid origins discovered in Africa

...nstitute evidence of an ancestral crown anthropoid lineage there." According to Seiffert, the latest findings help fill in the gap between later anthropoids and the oldest undisputed anthropoid, called Algeripithecus, found in Algeria, which lived around 45 million years ago. That species had been character...

Did feathered dinosaurs exist?

...may be a separate clade, distinctive from the main lineage of Theropoda, a remnant of early avian radiation, exhibiting all stages of flight and flightlessness." ...

Ancient trans-Atlantic swarm brought locusts to the New World

...rca locusts. The team found that the desert locust lineage gave rise to the more than 50 Schistocerca species found in the western hemisphere. ...

Missing fossil link 'Dallasaurus' found

... forms. Dallasaurus represents a clear link to one lineage of the later forms and the first time researchers can clearly show mosasaurs evolved fins from limbs within the different lineages of mosasaurs. With the aid of computer science and SMU's visualization laboratory, Polcyn has been able to simulate wh...

Wild Gorillas Handy with a Stick

...e required for tool use evolved before the gorilla lineage split off from humans and the other great apes—providing further evidence that intelligence is not unique to humans. ...

Scientists narrow the time limits for the human and chimpanzee split

...d infer a divergence of Old World monkeys from our lineage that is too old (50-to-60-million years ago) to reconcile with the current fossil record of primates," says Walker. What then is the next step? Although some additional improvement is possible by including more genes and more species, "the greatest...

Study finds evolution doesn't always favor bigger animals

...er species," said Roy. "The same species, the same lineage got bigger over time." In addition, the biologists discovered that the body size increases in nine species of ostracodes that evolved over that 40 million year span were commensurate with the change expected given how much the ocean temperatures de...

FSU biologist says new dinosaur is oldest cousin of Tyrannosaurus rex

...system, Erickson helped confirm the tyrannosauroid lineage of the two specimens by noting, among other features, the characteristic long hip, the U-shaped teeth and the fused nasal bridge. While they weren't exactly T. rex look-alikes, they were definitely family. But there were marked differences. Among th...

Sociality of sweat bees evolved simultaneously during climate change

...eturn' in social evolution in which members of the lineage are now unable to revert back to a solitary condition. These insects, however, seem to be able to revert fairly easily," he concluded. Halictid bees, which are important native pollinators in the Northern Hemisphere, where there are about 1,000 spec...

Most human-chimp differences due to gene regulation ?not genes

...at changed most dramatically, usually in the human lineage -- an indication of powerful incentives to adapt to a changing environment. Of the 1,056 genes from all four species, 60 percent had fairly consistent expression levels across all four species. "The expression levels of these genes seem to have rema...

Where 'jumping genes' fear to tread

...es, despite the fact that transposons entered each lineage independently, after each species diverged from a common ancestor. It appears that many TFRs are evolutionarily conserved features that existed prior to ?and have been largely maintained since ?the divergence of eutherian mammals and marsupials appr...

Progress being made in exploring potential use of stem cells to treat heart disease

...ly to guide and expand stem cells into the cardiac lineage but also to repress alternative cell fates Developing methods for safe delivery and proper integration of stem cells within patients' heart tissue to avoid such complications as arrhythmias (irregular heart beat) Solving immunological issues surr...

Researchers map out networks that determine cell fate

...atments for leukemias, in which a persistent mixed lineage seems to drive cancerous proliferation. Although ...titute of Technology. "Irreversible resolution of lineage priming appears to be a common feature of blood cell differentiation and may in fact be a general fe...

Researchers identify human DNA on the fast track

...chicken and the chimp. Incredibly, since the human lineage separated from that of the chimp, 18 of the 118 nucleotides have changed. This region "stood out," said Pollard. But what does it do? To find out, Pollard began working with the wet lab, led by Sofie Salama. Haussler established the wet lab followi...

HIV-1's high virulence might be an accident of evolution

...gene function was lost during viral evolution in a lineage that gave rise to HIV-1 and may have predisposed the simian precursor of HIV-1 for greater pathogenicity in humans." "Heightened immune activation is the only clear cut difference between pathogenic and non-pathogenic infections with the immunodefi...

Bone marrow may restore cells lost in vision diseases

...lved in the research. "To derive cells of neuronal lineage from cells of bone-marrow lineage is significant, if the finding stands up to the test of time. Compared to RPE transplantation, there...

Evolution reveals an independent route for diversity in animal form

...iverged very early on in animal evolution from the lineage leading to most other animal species. Cnidarians include reef-building polyps and pelagic jellyfish, while the group from which it split--the Bilateria--has given rise to the vast majority of the animals we are familiar with, including worms, fish, m...

Mobile DNA part of evolution's toolbox

... The LF-SINE was very active in the evolutionary lineage leading to the terrestrial vertebrates, but much l...lace before the origins of the mammals. But in the lineage leading to the coelacanth, the LF-SINE remained active, so that the coelacanth genome is now estimat...

Study suggests evolutionary link between diet, brain size in orangutans

...n evolution, where, relative to our ancestors, our lineage underwent a threefold expansion of brain size in a few million years." In their study, Taylor and van Schaik focused on several varieties of orangutans, an endangered primate closely related to humans. Members of the orang species inhabiting Suma...

New data from NIH lab confirms protocol to reverse type 1 diabetes in mice

...ed in the current work. NIH researchers used cell lineage tracking in the form of Y-chromosomal fluorescence in situ hybridization (FISH), in combination with insulin staining, to follow the fate of male spleen cells transplanted into female recipients. The female mice that received male donor cells consist...

Male chimpanzees prefer mating with old females

...olutionarily derived trait that arose in the human lineage sometime after the lineages giving rise to humans and chimpanzees diverged. ...

Muscle and bone from an ink-jet printer

...on of the MDSCs toward a myogenic or an osteogenic lineage in direct registration to patterns. The proof-of-concept experiment led to the formation of muscle- and bone-like tissues simultaneously in the same culture dish. The long-term promise of this new technology could be the tailoring of tissue-engine...

Lost in the labyrinth

...ed to more basic cell types higher up in the blood lineage hierarchy. Particular kinds of stem cells disappeared from the bone marrow of the mice. Others were too frequent. Bone marrow cells didn't develop into myeloid and red blood cells. B- and T-cells were also blocked at early stages, but in a different ...

Researchers seek to design first treatment for neuroAIDS

...glycogen synthase kinase 3 beta (GSK-3b) and mixed lineage kinase (MLK). "The number of HIV patients that su... a second molecular target, an enzyme called mixed lineage kinase 3 (MLK3) may be "of equal or greater importance" than GSK-3b. HIV exposure throws off the abi...

Neuron cell stickiness may hold key to evolution of the human brain

...asured the average rate of evolution in the human lineage in these sequences and then identified 992 elements with a significant excess of human-specific nucleotide substitutions relative to the baseline. This is about 79-percent more than we would expect to see by chance at our assigned probability thre...

Cloned mice created from fully differentiated cells, a milestone in cloning research

...nor cells for nuclear transfer among the different lineage cells, with 35 to 39 percent becoming a blastocyst, an early embryo consisting of about 100 to 150 cells, compared to 11 percent for the progenitor cells and only 4 percent for the stem cells. Only the granulocytes were able to produce two live clone...

Birth rate, competition are major players in hominid extinctions

...nce in San Francisco. Through time, the human lineage evolved to fill a wide variety of ecological niches, but those species that filled narrow environments, were less able to withstand the effects of climate change. Paranthropus boisei, a Pleistocene hominid, thrived around 2.5 million years ago, but ...

World's largest flower evolved from family of much tinier blooms

...rles C. Davis. "For nearly 200 years rafflesia's lineage has confounded plant scientists," says Davis, an a...ntly been abandoned, meaning that to determine its lineage we had to look at other parts of the plant's genome." Davis and his colleagues determined that ove...

New cell type identified in cancer development

...llmarks of normal bone marrow stem cells, nor the lineage markers most of the cancer cells had, but they did exhibit stem-like structure. The researchers suspected these unusual cells might be precancerous stems cells and designed several tests and experiments to find out more about them. They selected ...

In young mice, gregariousness seems to reside in the genes

Beyond the lineage of primates, according to scientific gospel, social behavior is dictated primarily by competition for resources such as food, territory and reproduction. That may well be true for many adult animals, but in a groundbreaking study researchers from th...

Man's best friend lends insight into human evolution

...g to Hare it seems to have evolved since the human lineage split from that of chimps a few million years ago. For Hare, who has worked with a number of different animal species, to understand the "unique" human ability to use social cues cooperatively we should look not just at our closest animal relative...

UI anthropologist, colleagues discover remains of earliest giant panda

...ed for more than three million years as a separate lineage apart from other bears and was adapted to eating bamboo very early in its development. “Pandas are very unique bears -– the only bear species that is known to exist wholly on a vegetarian diet,” says Ciochon. “The evolution of this unique dietary ...