or sets of all genes of five 19th century strains of the Phytophthora infestans pathogen with modern strains of the pathogen
The researchers found that the genes in historical plant samples collected in Belgium in 1845 as well as other samples collected from varied European locales in the late 1870s
and 1880s were quite different from modern-day P. infestans genes including some genes in modern plants that make the pathogen more virulent than the historical strains.
In one example a certain gene variant or allele called AVR3A that was not virulent in the historical samples was shown to be virulent in the modern-day samples.
and genes related to infection were also quite different Ristaino says. In the areas of the genome that today control virulence we found little similarity with historical strains suggesting that the pathogen has evolved in response to human actions like breeding more disease-resistant potatoes.
There are relatively fewer actively expressed genes or RNA. It is now possible to sequence RNA across kingdoms so a full snapshot can be taken of the active bacteria fungi protozoa and other microbes in the soil.
and African domestication events or did domestication result from different mutations in the same genes or even from mutations in different genes?
In a series of articles in the Journal of Evolutionary Biology and other journals Olsen postdoctoral researcher Cindy Vigueira and their colleagues have shown that different mutations of the same genes underlie the loss of shattering and the straw
For example the weeds carry the crop form of the loss-of-shattering gene which means that they branched off from the crops sometime after people selected for loss of shattering.
This means the weedy forms can draw on both ancestral genes and crop genes as they respond to the selection pressures of modern agriculture.
Even though both weedy strains arose in Asia he says weedy rice became a problem in Southeast asia only in the last few decades.
It's basically a single amino-acid change in a particular gene although newer varieties are getting a bit fancier and multiple genes may be involved.
So it would be pretty easy for random mutations to confer resistance on the weeds.
The other possibility is that resistance genes will migrate from the crop to the weeds.
Because both cultivated rice and weedy rice tend to self-fertilize there hasn't been a lot of gene flow going on in rice in general Olsen says.
now that selective pressure is favoring gene flow. We're already seeing more and more hybridization occurring Olsen says.
Parasitization caused changes in the levels of active genes in the brains of infected bees.
Varroa altered the activity of 455 genes including genes involved in GABA and serotonin signaling while Nosema affected 57.
Twenty genes were common between the two infections and several of the up-regulated genes are involved in oxidative stress neural function and foraging behavior.
Parasitized bees also tended to have a higher viral infection as well adding to their disease burden
RNA interference is a natural process that affects the level of activity of genes in animals and plants.
however successfully artificial interfering RNAS that target genes in insect pests slowing their growth or killing them.
For example an interfering RNA might have unintended the effect of suppressing the action of a gene needed for reproduction in a beneficial species. Standard laboratory testing would detect no harm
A genome-wide analysis of an uropathogenic E coli revealed that expression of the gene that encodes for the bacteria's flagellar filament was decreased in the presence of cranberry PACS.
or 16s RIBOSOMAL RNA genes that are conserved across microbial lineages because of their essential role as housekeeping genes--critical for the organism's survival.
This course correction provides insights into how organisms function in the context of a particular ecosystem as well as a much improved and more accurate understanding of the associations of newly discovered genes with resident life forms.
Sex still worthwhilebased on the gene analyses the scientists were also able to prove that mildew already lived parasitically on the ancestral form of wheat 10000 years ago before wheat were domesticated actually as crops.
#Understanding bulls gene-rich Y chromosomes may improve herd fertilitythe Y chromosomes of cattle have more genes
The researchers identified 1274 genes in the male specific region of the bovine Y chromosome compared to the 31 to 78 genes associated in the Y chromosomes of various primates.
They also said the genes in the bovine Y chromosome were much more transcriptionally active compared to other mammals.
In addition to the 1274 genes that take part in coding proteins they also identified 375 novel noncoding gene families on the bovine Y chromosome
which does not have a large number of genes and is considered mostly transcriptionally inactive Liu said.
Currently the gene content and transcription pattern of the bovine Y chromosome is the only non-primate Y chromosome that researchers have studied in depth according to Liu.
These findings directly contradict the traditional view that the Y is largely heterochromatic with a paucity of genes
which determines the gene content and transcriptional activity of the Y chromosome among cattle according to Liu.
With little knowledge of the roles that the Y chromosome genes play in fertility most animal breeders and farmers select bulls based on physical characteristics such as the size of the testis.
Because the Y chromosome is present in males only the Y-linked testis genes that govern male fertility are passed directly through the male line.
The researchers analyzed the expression of the entire Y-linked genes as the bull aged beginning soon after the bull's birth during puberty and then again after the bull matured.
He believes that how bacteria which might carry resistant genes are transmitted to humans must be considered
#Plant molecular biologist are getting to the root of the matterworking to identify key genes in the root development of poplar trees three Michigan Technological University scientists have come up with a new model for how genes interact
They also identified a network of genes that cause poplar roots to grow well in low-nitrogen soil making them ideal candidates for biofuel tree plantations on marginal lands.
There are tens of thousands of genes in the poplar genome. The challenge--and it was a big one--was how to determine which genes are doing
what how they affect each other and how they work together to regulate root growth under low nitrogen conditions.
He took on the task of untangling the interactions of more than 61000 genes by searching for a high hierarchical regulator the boss gene.
The scientists did a series of experiments over time under the same experimental conditions to identify the genes involved in the changes they observed.
They found 9. 198 genes that produced significantly different amounts or kinds of proteins at six different times.
By performing genetic network analyses they narrowed the field to a handful of key genes that appeared to control the majority of the 9198 others.
Further analysis closed in on a gene called Ptanac1. When we tweak this gene the entire network responds
and the roots grow 58 percent more than controls'says Busov. What Wei wound up with is a new model of how genes function together.
Imagine a manufacturer he says. At the bottom of the hierarchy you find the laborers They answer to a foreman who reports to a manager and so on until you get to the president.
It is also the first study to get an accurate picture of how specific genes are switched on in the human mammary gland during lactation.
They then created the first publicly accessible library of genes expressed in the mammary gland based on RNA-sequencing technology.
This approach revealed a highly sensitive portrait of the genes being expressed in human milk-making cells.
They discovered an orchestrated switching on and off of various genes as the mammary gland transitions from secreting small amounts of immunity-boosting colostrum in the first days after giving birth to the copious production of milk in mature lactation.
In particular the PTPRF gene which is known to suppress intracellular signals that are triggered usually by insulin binding to its receptor on the cell surface may serve as a biomarker linking insulin resistance with insufficient milk supply.
It is also the first study to get an accurate picture of how specific genes are switched on in the human mammary gland during lactation.
They then created the first publicly accessible library of genes expressed in the mammary gland based on RNA-sequencing technology.
This approach revealed a highly sensitive portrait of the genes being expressed in human milk-making cells.
They discovered an orchestrated switching on and off of various genes as the mammary gland transitions from secreting small amounts of immunity-boosting colostrum in the first days after giving birth to the copious production of milk in mature lactation.
In particular the PTPRF gene which is known to suppress intracellular signals that are triggered usually by insulin binding to its receptor on the cell surface may serve as a biomarker linking insulin resistance with insufficient milk supply.
#Insecticide causes changes in honeybee genes, research findsnew research by academics at The University of Nottingham has shown that exposure to a neonicotinoid insecticide causes changes to the genes of the honeybee.
The study published in the online journal PLOS ONE supports the recent decision taken by the European commission to temporarily ban three neonicotinoids amid concerns that they could be linked to bee deaths.
and insecticides but this is the first comprehensive study to look at changes in the activity of honeybee genes linked to one of the recently banned neonicotinoids imidacloprid.
and showed that a very low exposure of just two parts per billion has an impact on the activity of some of the honeybee genes.
and increase the activity of genes involved in breaking down toxins most likely to cope with the insecticide.
Genes involved in regulating energy to run cells were affected also. Such changes are known to reduce the lifespan of the most widely studied insect the common fruit fly
This is a very significant piece of research which clearly shows clear changes in honeybee gene activity as a result of exposure to a pesticide
Resistance gene found against Ug99 wheat stem rust pathogenthe world's food supply got a little more plentiful thanks to a scientific breakthrough.
Eduard Akhunov associate professor of plant pathology at Kansas State university and his colleague Jorge Dubcovsky from the University of California-Davis led a research project that identified a gene that gives wheat plants resistance to one of the most deadly races of the wheat
The team's study Identification of Wheat Gene Sr35 that Confers Resistance to Ug99 Stem Rust Race Group appears in the journal Science.
It identifies the stem rust resistance gene named Sr35 and appears alongside a study from an Australian group that identifies another effective resistance gene called Sr33.
This gene Sr35 functions as a key component of plants'immune system Akhunov said. It recognizes the invading pathogen
and triggers a response in the plant to fight the disease. Wheat stem rust is caused by a fungal pathogen.
or three genes that were so efficient against stem rust for decades that this disease wasn't the biggest concern Akhunov said.
As a first line of defense wheat breeders and researchers began looking for resistance genes among those that had already been discovered in the existing germplasm repositories he said.
The Sr35 gene was one of those genes that was discovered in einkorn wheat grown in Turkey Akhunov said.
Until now however we did not know what kind of gene confers resistance to Ug99 in this wheat accession.
To identify the resistance gene Sr35 the team turned to einkorn wheat that is known to be resistant to the Ug99 fungal strain.
Researchers spent nearly four years trying to identify the location of the Sr35 gene in the wheat genome which contains nearly two times more genetic information than the human genome Once the researchers narrowed the list of candidate genes they used two complementary approaches to find the Sr35 gene.
It was a matter of knocking out each candidate gene until we found the one that made a plant susceptible Akhunov said.
Next researchers isolated the candidate gene and used biotechnical approaches to develop transgenic plants that carried the Sr35 gene
and showed resistance to the Ug99 race of stem rust. Now that the resistance gene has been found Akhunov
and colleagues are looking at what proteins are transferred by the fungus into the wheat plants
and recognized by the protein encoded by the Sr35 gene. This will help researchers to better understand the molecular mechanisms behind infection
which genes are active or being transcribed between the domestic tomato and its wild cousins. The results give insight into the genetic changes involved in domestication
The new study shows that a large block of genes from one species of wild tomato is present in domestic tomato
Among other findings genes associated with fruit color showed rapid evolution among domesticated red-fruited tomatoes
And S. pennellii which lives in desert habitats had accelerated evolution in genes related to drought tolerance heat and salinity.
New technology is giving biologists the unprecedented ability to look at all the genes in an organism not just a select handful.
but also the MESSENGER RNA being transcribed from different genes. RNA transcription is the process that transforms information in genes into action.
If the DNA sequence is the list of parts for making a tomato plant the MESSENGER RNA transcripts are the step-by-step instructions.
Gene expression profiling combined with an understanding of the plants'biology allows researchers to understand how genes interact to create complex phenotypes said Neelima Sinha professor of plant biology at UC Davis
Genomics has tracked fast previous gene-by-gene analyses that took us years to complete she said.
but differences in the expression of the genes encoding these enzymes did not fully explain the rotation-resistant beetles'advantage.
which the genes for all three transcription factors were disabled. Then he took the pollen from each to pollinate normal flowers.
which pollen tube-expressed genes were being regulated by the MYB transcription factors. In pollen tubes that had grown through pistils they found 11 that were grossly underexpressed in the mutated pollen tubes compared to normal ones.
what those genes do. They encode a variety of tasks but one in particular got Leydon's attention
In other words expressing that gene could be pushing the pollen tube's self-destruct mechanism. This is not just a dialogue
Future work Johnson said will include tracking down the relevant genes more fully and determining whether thionin is indeed the pollen tube buster that the genes
and their MYB-related expression seem to indicate. The work may also have implications beyond basic science Johnson said.
Thousands of plant genes activated by ethylene gasit's common wisdom that one rotten apple in a barrel spoils all the other apples
--but now the genes underlying these phenomena of nature have been revealed. In the online journal elife a large international group of scientists led by investigators at the Salk Institute for Biological Studies have traced the thousands of genes in a plant that are activated once ethylene a gas that acts as a plant
growth hormone is released. This study the first such comprehensive genomic analysis of ethylene's biological trigger may lead to powerful practical applications the researchers say.
Teasing out the specific genes that perform each of these discrete functions from the many genes found to be activated by ethylene might allow scientists to produce plant strains that slow down growth
Now that we know the genes that ethylene ultimately activates we will be able to identify the key genes
Now we can see that by altering the expression of one protein ethylene produces cascading waves of gene activation that profoundly alters the biology of the plant.
What genes are turned on? And what are those genes doing? Using a technique known as Chip-Seq the researchers exposed Arabidopsis to ethylene and identified all the regions of the plant genome that bound to EIN3
which required using next-generation sequencing. They then used genome-wide mrna sequencing to identify those targeted genes
whose expression actually changes due to interaction with EIN3. Not all genes targeted by EIN3 have changes in their gene expression Ecker says.
They found that thousands of genes in the plant responded to EIN3. Then the investigators discovered two interesting things.
First when EIN3 is activated by ethylene it goes back to control the genes in the pathway that were used to activate the EIN3 transcription factor in the first place.
That tells us that a plant making a critical master regulator like EIN3 wants to keep that production pathway under very tight control Ecker says.
if resistance genes are initially rare in pest populations; inheritance of resistance is recessive--meaning insects survive on Bt plants
only if have two copies of a resistance gene one from each parent --and abundant refuges are present.
In isolated pockets of trees the gene pool is diminished also meaning the seeds produced may be less viable over time.
and comparisons with other varieties to highlight a gene involved in pod colour variation. Zooming further in on the gene sequence they then identified a single DNA letter change that affected levels of the gene's expression and so the colour of the pod.
Cacao plant breeders trying to produce a delicious high-yield strain through cross breeding have met with limited success. So the genetic marker could in theory be used to screen young seedlings
#Gene that helps honey bees find flowers (and get back home) discoveredhoney bees don't start out knowing how to find flowers
and orient themselves in relation to the sun. In a new study researchers report that a regulatory gene known to be involved in learning
Activity of this gene called Egr quickly increases in a region of the brain known as the mushroom bodies
This gene is the insect equivalent of a transcription factor found in mammals. Transcription factors regulate the activity of other genes.
The researchers found that the increased Egr activity did not occur as a result of exercise the physical demands of learning to fly
This discovery gives us an important lead in figuring out how honey bees are able to navigate so well with such a tiny brain said Gene Robinson a professor of entomology
and neuroscience and director of the Institute for Genomic Biology at the University of Illinois. And finding that it's Egr with all that this gene is known to do in vertebrates provides another demonstration that some of the molecular mechanisms underlying behavioral plasticity
Largest ever to be mappedswedish scientists have mapped the gene sequence of Norway spruce (the Christmas tree)--a species with huge economic and ecological importance
The scientists have identified about 29000 functional genes marginally more than humans have but the question arises:
An international research team headed up by evolutionary biologists at the University of Zurich has identified now two genes responsible for the flowering of a tropical deciduous tree species Shorea beccariana.
After drought periods the two genes Sbft and Sbsvp undergo dramatic transcriptional changes directly before flowering.
The researchers can also confirm the flowering functions of these two genes using transgenic Arabidopsis thaliana plants. 85-meter canopy crane necessary for sample collectionthe Phd student Masaki Kobayashi his supervisor Professor
In this way Kobayashi and Shimizu identified 98 genes that are associated with the flowering of the plant-including the genes Sbft and Sbsvp
The genes that have been identified now indicate when mass flowering is about to happen. Successively monitoring of gene activity can help predict
when mass flowering will take place explains Kobayashi. This will make it possible to coordinate the collection of seeds
We are currently investigating the use of these new materials for biomedical applications such as drug/gene delivery cross linkable hydrogel materials and skin adhesives.
and gene-family expansion in genes associated with energy metabolism and oxygen transmission indicating that gene categories involved in energy metabolism appear to have an important role for Tibetan antelope via efficiently providing energy in conditions of low partial pressure of oxygen (PO2).
Further research revealed that both the Tibetan antelope and the highland American pika have signals of positive selection for genes involved in DNA repair and the production of ATPASE.
Considering the exposure to high levels of ultraviolet radiation positive selective genes related to DNA repair may be vital to protect the Tibetan antelope from it.
Qingle Cai Project manager from BGI said The completed genome sequence of the Tibetan antelope provides a more complete blueprint for researchers to study the genetic mechanisms of highland adaptation.
and analyzed more than 1000 genes--approximately 20 percent of the entire yeast genome--from each of 23 yeast species. He quickly realized that the histories of the 1000-plus genes were all slightly different from each other as well as different from the genealogy constructed from a simultaneous analysis of all the
genes. I was surprised quite by this result Salichos pointed out. By adapting an algorithm from information theory the researchers found that they could use these distinct gene genealogies to quantify the conflict
and focus on those parts of the tree that are problematic. In broad terms Rokas and Salichos found that genetic data is less reliable during periods of rapid radiation
and analyzed more than 1000 genes--approximately 20 percent of the entire yeast genome--from each of 23 yeast species. He quickly realized that the histories of the 1000-plus genes were all slightly different from each other as well as different from the genealogy constructed from a simultaneous analysis of all the
genes. I was surprised quite by this result Salichos pointed out. By adapting an algorithm from information theory the researchers found that they could use these distinct gene genealogies to quantify the conflict
and focus on those parts of the tree that are problematic. In broad terms Rokas and Salichos found that genetic data is less reliable during periods of rapid radiation
The new technology platform can harness the plant's own genes to improve characteristics of sunflower develop genetic traits
Genetic analysis of these isolates revealed high homology across all eight gene segments. The analysis of these novel H7n9 influenza virus isolates showed that that the six internal genes were derived from avian H9n2 viruses
but the ancestor of their hemagglutinin (HA) and neuraminidase (NA) genes is unknown. HA receptor-binding specificity is a major molecular determinant for the host range of influenza viruses.
Within the HA protein of novel H7n9 viruses there was a leucine residue at position 226
which is characteristic of the HA gene in human influenza viruses. This finding implies that H7n9 viruses have acquired partially human receptor-binding specificity.
The researchers who sequenced it say that 97 percent of the genome consists of genes--bits of DNA that code for proteins--and small pieces of DNA that control those genes.
which for genes feeds into the machinery that makes proteins. But Herrera-Estrella Albert and their colleagues argue that organisms may not bulk up on genetic junk for reasons of benefit.
U. gibba has about 28500 genes comparable to relatives like grape and tomato which have much larger genomes of about 490 and 780 million base pairs respectively.
but at the same time maintaining a functional set of genes similar to those of other plant species says Herrera-Estrella.
Some of the duplicated genes retain their original structure and function and so produce more of a given gene product--a protein for example he said.
Some gradually adapt new forms to take on new functions. If those changes are beneficial the genes persist;
if they're harmful they disappear from the genome. Many agricultural crops benefit from genome duplications including banana papaya strawberry sugarcane watermelon
A large proportion of the duplicated genes (about 40 percent) have been retained they report. A neat thing about the duplication is that we can look at the genes that were retained
and see if they are in specific pathways Vanburen said. The researchers found evidence that duplicated genes related to wax formation
which allows the plant to repel water and remain clean) and survival in a mineral-starved watery habitat were retained for example.
By looking at changes in the duplicated genes the researchers found that lotus has a slow mutation rate relative to other plants Ming said.
and birds focusing on the gene that codes for the viral hemagglutinin (HA) protein. After comparing HA genetic sequences in five key locations that control the viruses'interactions with infected hosts the researchers calculated an antigenic index for each strain.
One of the amazing things about the influenza virus is its ability to grab genes from different pools he says.
There could be viral genes that mix among pigs or between birds and pigs. Sasisekharan and colleagues are now doing a similar genetic study of H5 influenza strains.
and his team identified several immune gene signatures that reflect the abundance and anti-tumor properties of different types of tumor-infiltrating immune cells.
In these cases high expression levels of the immune genes predicted for recurrence-free survival
To do this they turned to two different mouse models each specially engineered to produce distinct but related proteins that turn muscle-specific genes on and off.
The first model dubbed the marathon mouse has a muscle-gene regulator called PPARÎ/Î'.These mice can run much further than normal mice.
The second model known as the couch potato mouse produces a different muscle-gene regulator called PPARÎ.
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