| Chromosome (232) |  |
| Chromosome (232) | |
study published by Walsh's lab in 2014 used single-neuron sequencing to detect copy number variants--another type of mutation affecting the number of copies of chromosomes or chromosome fragments.
The prostate cancer study identified 20"hotspots"of greatest chromosomal instability as additions or deletions in less than 0. 5 percent of the total DNA present in human chromosomes.
Non-genetic material is material that is not part of the chromosomes, the chains in the cell nucleus
'the part of the chromosome (a long structure of DNA found in the cell nucleus, containing all the characteristics of a living organism) that controls its behaviour.
Telomeres are caps on the ends of chromosomes. Every time a cell divides the telomeres get a little shorter.
which protects the ends of our chromosomes from damage, are extremely likely to develop melanoma, new research shows.
regions that protect chromosomes from damage. The team found that there were also cases of other cancer types in families with these hereditary mutations such as leukemia
or chromosomes that can be beneficial to the organism s survival. The results are published in the journal PLOS Biology. hese studies turn our view of the functions of sex by 180 degrees
or having more than the normal number of DNA-packaging chromosomes. Aneuploidy is well known to be deleterious in humans causing genetic disorders like Down s syndrome or trisomy 21.
But having an extra chromosome can actually be beneficial in microbes like Cryptococcus where it has been shown to confer drug resistance to the antifungal fluconazole.
For example offspring with an extra copy of chromosome 9 or 10 became drug resistant and were able to outcompete their parent
or adaptive the fungi can lose the chromosome just as easily as they gained it. In fact we showed that
and let them lose their extra chromosomes they also lose their new properties and go back to behaving just like their parent did. he key finding he says llustrates how unisexual reproduction introduces limited genetic diversity in clonal populations already well adapted to an environment
despite having A y chromosome rodents lacking the mjd1aenzyme developed as females. The findings are detailed in a study published in the journal Science.
and share the same number of chromosomes but fertilization often fails at the pollen tube burst
#Synthetic yeast chromosome paves the way for designer genomes A chunk of the genetic blueprint for yeast has been created
and joined them together to create a synthetic version of a chromosome the structure that contains DNA inside cells from brewer's yeast.
The ability to create such chromosomes is a major step for the field of synthetic biology which aims to engineer microbes to produce useful products.
For me one of most exciting aspects is the fact that we've so extensively edited the sequence of natural chromosome
How Synthetic Yeast Chromosome Was created Boeke was leader of the study detailed on March 27 in the journal Science.
To create the artificial chromosome Boeke and his team used computer software to design a modified version of yeast chromosome III which they called syniii
and incorporated it into brewer's yeast (Saccharomyces cerevisiae). They chose this chromosome because it is the smallest of yeast's 16 chromosomes controlling how the cells mate
and experience genetic changes. It took the researchers seven years to stitch together the synthetic chromosome from pieces of DNA.
The language of DNA consists of four letters A t G and C which form bonds called base pairs.
The syniii chromosome contains 272871 base pairs slightly fewer than the 316617 base pairs in chromosomes of native yeast or natural yeast on
which the simulated one is based. Undergraduate students at Johns hopkins university did much of the work fusing together short pieces of DNA into longer segments as part of a class project
which randomly move around in the chromosome. The researchers also added tags to the DNA to label it as native or synthetic.
The completed chromosome was remarkably normal Boeke said adding that the yeast with the synthetic DNA behave almost identically to wild yeast cells.
In recent years scientists have created synthetic chromosomes from bacteria and viruses but this is the first time anyone has built a chromosome from a eukaryote an organism
whose cells have nuclei. Craig Venter and his team at the J. Craig Venter Institute who created the first synthetic bacterium in 2010 praised the new achievement.
This work is another remarkable example of how synthetic biology can be used to rewrite chromosome sequences at a sizable scale Venter
Ultimately the researchers plan to synthesize a complete yeast genome with all 16 chromosomes. Boeke's team plans to synthesize larger chromosomes
and do it faster and more cheaply. Despite its utility the work poses questions about the ethics of creating man-made genomes especially in more complex organisms such as animals.
Right now the cost of synthesizing chromosomes is prohibitively high but that could change if the technology improves Boeke said.
He predicts that designer mini-chromosomes will be developed first building on gene therapy which seeks to treat diseases by replacing defective genes with functional ones.
Different genes, same consequences Another cause of autism and intellectual disability is the loss of a series of genes on human chromosome 16,
They#ve also known that chromosome 21 plays a role in the disease due to Alzheimer s-like symptoms in people with Down syndrome (with three copies of chromosome 21.
This chromosome contains the APP gene which can lead to production of the primary component of the damaging amyloid plaques.
but it also converts to a DNA form that allows it to weave its genes into a human chromosome.
They also successfully targeted another antibiotic resistance gene encoding SHV-18 a mutation in the bacterial chromosome providing resistance to quinolone antibiotics and a virulence factor in enterohemorrhagic E coli.
Different genes, same consequences Another cause of autism and intellectual disability is the loss of a series of genes on human chromosome 16,
The system can also distinguish between homozygous genotypes (where a person caries the same SNP on each member of a pair of chromosomes)
and heterozygous genotypes (where a person carries different SNPS on each chromosome). The patented warfarin test kit is available for commercialization
When a chromosome gets chopped into several pieces and reassembled as often happens in cancer even undamaged genes are expressed at different levels than in a normal chromosome.
Raj also discovered that in genetically identical worms varying levels of gene transcription could mean the difference between a long life and an early death.
That because HIV integrates its genetic material into the chromosomes of some white blood cells, helping it escape notice of the immune system.
Improper repair of DNA lesions can lead to mutations, abnormal chromosome structures, or loss of genetic information that in turn can cause premature aging, cancer, and genetic abnormalities.
However, the majority of tools for the analysis of DNA are designed for diploid organisms, such as humans, with one set of chromosomes,
. which has multiple sets of chromosomes. Scientists from The Genome Analysis Centre (TGAC) and John Innes Centre have developed a bioinformatics pipeline
or to study the 3-D structure of normal chromosomes by testing whether two genes located far from each other on a chromosome fold in such a way that they end up next to each other,
the researchers say
#Bioadhesive Nanoparticles Help Protect Your Skin From the Sun Dermatologists from Yale university have developed a new sunscreen made with bioadhesive nanoparticles that doesn penetrate the skin,
in which progerin is linked to telomeresepetitive DNA sequences that protect the ends of human chromosomes
#Structured Illumination Microscopy and SPA Help Study SPB Duplication in Living Yeast Cells Cellular mitosis depends in part on small organelles that extend spindles to pull apart chromosome pairs.
or to study the 3-D structure of normal chromosomes by testing whether two genes located far from each other on a chromosome fold in such a way that they end up next to each other,
the researchers say
#Liquid crystals Detect Protein Fibers Associated with Development of Neurodegenerative Diseases Liquid crystals are familiar to most of us as the somewhat humdrum stuff used to make computer displays and TVS.
and reform into spindles that are used by the dividing cell to move chromosomes. For chromosome migration to occur,
the microtubules attached to them must disassemble, carrying the chromosomes in the process. The dynamic instability that makes it possible for microtubules to transition from a rigid polymerized
or"assembled"nucleotide state to a flexible depolymerized or"disassembled"nucleotide state is driven by guanosine triphosphate (GTP) hydrolysis in the microtubule lattice."
or mechanical stress on the chromosomes into which our genetic material is packaged. To make sure cells stay alive
For instance, different regions of a chromosome can fuse together, causing genes to rearrange themselves --and such chromosome fusions can lead to diseases such as cancer.
To learn more about the process, Kapoor, Kleiner and their colleagues zeroed in on the sites in chromosomes where DNA repair happens.
Specifically they focused on a single histone, a type of protein that DNA wraps around to make up chromosomes.
This histone, H2ax, is known to be involved in DNA repair. Immediately after DNA damage occurs, H2ax gets a mark--it becomes tagged with a chemical moiety known as a phosphate.
Patients with Down syndrome have three copies of chromosome 21 in their cells. Theye also 20 times more likely to contract childhood B-cell acute lymphoblastic leukemia than the general population,
making that chromosome an important avenue for researching the genetic basis of the cancer. major goal of my laboratory is to identify the specific gene or genes on chromosome 21 responsible for the increased incidence of leukemia in this population,
In previous work, Crispino and colleagues found that a gene on chromosome 21 called DYRK1A contributes to the development of leukemia.
Because they have extra copies of chromosome 21, children with Down syndrome have more DYRK1A than usual. his finding is exciting to us
People with Down syndrome have an extra copy of the 21st chromosome where the production gene for the beta amyloid protein resides.
or to study the 3-D structure of normal chromosomes by testing whether two genes located far from each other on a chromosome fold in such a way that they end up next to each other,
the researchers say
#Researchers Discover Method to Measure Stiffness of Arteries in the Brain UCLA researchers have discovered a noninvasive method to measure vascular compliance,
If granted, it will be only the second occasion where the chromosome of human embryos have been modified.
of chromosomes passed on to future generations. But it continues to attract controversy as critics fear DNA alterations could create unforeseen health problems that would be passed down from generation to generation of the population.
#Gene on-off switch works like backpack strap A research team based in Houston's Texas Medical center has found that the proteins that turn genes on by forming loops in human chromosomes work like the sliding plastic adjusters on a grade-schooler
"Aiden said that one of the most astonishing implications of the new model is that loops on different chromosomes tend not to become entangled."
"But this process would lead to interweaving loops and highly entangled chromosomes. This is a big problem
if you need those chromosomes to separate again when the cell divides.""The tri-glide takes care of that,
and reform into spindles that are used by the dividing cell to move chromosomes. For chromosome migration to occur,
the microtubules attached to them must disassemble, carrying the chromosomes in the process. The dynamic instability that makes it possible for microtubules to transition from a rigid polymerized
or"assembled"nucleotide state to a flexible depolymerized or"disassembled"nucleotide state is driven by guanosine triphosphate (GTP) hydrolysis in the microtubule lattice."
or to study the 3-D structure of normal chromosomes by testing whether two genes located far from each other on a chromosome fold in such a way that they end up next to each other,
the researchers say
#New frontiers in 3d printing Three dimensional printing is revolutionizing the production of new devices and structures, including soft robots,
#Gene on-off switch works like backpack strap A research team based in Houston Texas Medical center has found that the proteins that turn genes on by forming loops in human chromosomes work like the sliding plastic adjusters on a grade-schooler backpack.
Aiden said that one of the most astonishing implications of the new model is that loops on different chromosomes tend not to become entangled. n the old model,
Aiden said. ut this process would lead to interweaving loops and highly entangled chromosomes. This is a big problem
if you need those chromosomes to separate again when the cell divides. he tri-glide takes care of that,
and proteins that produces chromosomes inside cell nuclei -which helps it to maintain gene expression patterns that are put in place during early development.
DNA sequence or chromosome--linked to increased AD risk. The researchers next conducted a meta-analysis of these 55 variants across four independent AD study cohorts,
encompassing almost 145,000 persons with AD and healthy controls, revealing two genome-wide significant variants on chromosomes 4 and 10.
sometimes involving multiple chromosomes that swap pieces when they break and reassemble. St jude has made CONSERTING available for free to researchers worldwide.
"Differentiated hepatocytes have amplified their chromosomes, "he explains. That is, the cells have more than the usual two copies of every chromosome."
"This enables the cells to make more proteins, but it really compromises their ability to divide."
the labeled cells had only two copies of each chromosome. By following the descendents of the stem cells for up to a year,
The cell nucleus is a ball of chromosomes wrapped in a protective fatty membrane. In this study, the researchers discovered that treating astrocytes with TGF-beta freed a small piece of the p75ntr protein to bind to nucleoporins,
and Chromosomes,"examining the impact of marijuana on embryonic cells--in The Lancet in 1969, as a master's student at the University of the West indies in her native Jamaica.
or to study the 3-D structure of normal chromosomes by testing whether two genes located far from each other on a chromosome fold in such a way that they end up next to each other,
the researchers say y
#Silicone vaginal rings deliver antiviral drugs, protect women against HIV Researchers at University Jean Monnet of Saint-Etienne,
where it exists as an"artificial chromosome"separate from the yeast cell's own genome.
or loosely chromosomes are wound and thus accessible for genes to be expressed. One of these targets is called ARID1A,
a bundle of protein threads that pull the chromosomes towards the opposite poles of the cell and distributes them equally between the new cells.
Artistic rendering shows pig chromosomes (background) which reside in the nucleus of pig cells and contain a single strand of RNA,
first mapped the gene causing North carolina macular dystrophy on chromosome 6 in 1992. The current findings ultimately required an international team of 20 investigators using data from the Human genome Project
In line with women's health, connected care plays a crucial role in keeping the world's XX-chromosomes healthy.
and repressing gene expression. or the first time we see that the structure of the chromosomes contributes to gene controlsays Whitehead Member Richard Young who is also a professor of biology at MIT. n the past there have been all kinds of ideas around how the structure might affect gene control
elements to highly condensed chromosomes. Working in mouse embryonic stem cells (ESCS) the Young lab examined the scaffolding landscape found within topologically associated domains.
Maggert explains that chromosomes are located in the nuclei of all human cells and the DNA material in these chromosomes is made up of coding and non-coding regions.
The coding regions known as genes contain the information necessary for a cell to make proteins
Images of the gigantic protein in unprecedented detail will transform scientists'understanding of exactly how cells copy their chromosomes
which a cell copies its chromosomes and pulls them apart into two separate cells. Mitosis is used in cell division by all animals and plants.
and mesh with other units at different points in the cell cycle allowing it to control a range of mitotic processes including the initiation of DNA replication the segregation of chromosomes along protein'rails'called spindles and the ultimate splitting of one
which a deletion on chromosome 22 causes problems such as learning and memory deficits, are building a database of information from genomic tests, clinical medical records, extensive family surveys and histories,
just two years after chromosome 22 was sequenced. t just sitting there waiting to be used. s
but it possible to engineer an organism chromosomes to alter those odds. Researchers have used already the idea to design mosquitoes that only make male offspring
#Yeast 2. 0 Designer changes in the first artificial yeast chromosome could help advance synthetic biology.
Scientists have synthesized an entire yeast chromosome, the first artificial chromosome for the kingdom of life that includes humans, plants, and fungi.
Yeast with the artificial chromosome appeared to be just as happy as their aturalcounterparts, reports the team.
The methods developed to create the designer genomic structure could help synthetic biologists better use the single-celled fungi as biological factories for chemicals like biofuels and drugs.
The report of the first artificial, designer yeast chromosome suggests ways for researchers to produce new chemicals in the microbes
Six years ago, the J. Craig Venter Institute built the first artificial chromosome, which encompassed the complete genome of a bacterium (see ynthesizing a Genome From scratch.
The first synthetic yeast chromosome, reported in Science on Thursday, represents just part of that organism complete genome
The Johns hopkins university-led team first designed the chromosome on a computer, streamlining the natural chromosome sequence
Then, other researchers continued to assemble those blocks into longer stretches of the chromosome, and eventually the largest chunks were delivered into yeast cells,
which took over the last assembly steps to create the whole, artificial chromosome. The artificial chromosome is a designer version of just one of the yeast 16 chromosomes,
and the smallest one at that. But the work is an important step forward for synthetic biology
In addition to deleting some unnecessary sequences from the code of their designer chromosome, the researchers also flanked many genes on the chromosome with tiny bits of DNA that act as landing sites for a protein that can be used to create on-demand mutations.
With these designer changes, the researchers say they will be able to test how many mutations a yeast genome can tolerate at once
Lead researcher Jef Boeke tells The Verge that the team plans to create these mutation-ready additions in all 16 chromosomes.
A cell needs to share chromosomes accurately when it divides otherwise the two new cells can end up with the wrong number of chromosomes.
This is called aneuploidy and this has been linked to a range of tumours in different body organs.
The mitotic spindle is responsible for sharing the chromosomes and the researchers at the University believe that the mesh is needed to give structural support.
and cells had trouble sharing chromosomes during division. Dr Emma Smith, senior science communications officer at Cancer Research UK, said:
roblems in cell division are common in cancer cells frequently end up with the wrong number of chromosomes.
This early research provides the first glimpse of a structure that helps share out a cell chromosomes correctly
#New cell division mechanism discovered Canadian and British researchers have discovered that chromosomes play an active role in animal cell division.
and it was unknown until now that chromosomes could play an active role at this step in cytokinesis.
the separation of chromosomes followed by splitting of the cell into two new daughter cells by cytokinesis."
called microtubules, were involved in pulling chromosomes to opposite poles of the cell during the division process."
"At this time, microtubules physically separate the chromosomes via their central kinetochores while other microtubules signal to the cortex of the cell where its equator is, i e.,
Furthermore until now, it was believed that the chromosomes only played a passive role: that they were pulled by the microtubules
Chromosomes'active role Initially working with the cells of fruit flies using powerful genetic tools and sophisticated microscopy,
the research team discovered that chromosomes emit signals that influence the cortex of the cell to reinforce microtubule action.
"When chromosomes are segregated, they approach the membrane at the poles of the cell, and thanks to this enzyme's actions, this contributes to the softening of the polar membrane,
Blood samples were analysed using a technique called'massively parallel sequencing'to look for an excess of genetic material from chromosome 21
A cell needs to share chromosomes accurately when it divides otherwise the two new cells can end up with the wrong number of chromosomes.
This is called aneuploidy and this has been linked to a range of tumours in different body organs.
The mitotic spindle is responsible for sharing the chromosomes and the researchers at the University believe that the mesh is needed to give structural support.
and cells had trouble sharing chromosomes during division. Dr Emma Smith, senior science communications officer at Cancer Research UK, said:
roblems in cell division are common in cancer cells frequently end up with the wrong number of chromosomes.
This early research provides the first glimpse of a structure that helps share out a cell chromosomes correctly
but no cancer, to a situation where large pieces of genetic information were being transferred not just between genes but between chromosomes.
a rare hereditary disease in which a mutation of the MEN1 gene on chromosome 11 makes patients susceptible to developing both benign
because cells in any one tumor have chromosomes with different telomere lengths and any one cell's telomeres must be shortened critically to induce death. 6-thiodg is used preferentially as a substrate by telomerase
They report previously unidentified chromosome duplications and confirmed data from earlier findings that associated these tumors with the KIT gene,
A cell needs to share chromosomes accurately when it divides otherwise the two new cells can end up with the wrong number of chromosomes (aneuploidy)
which has been linked to a range of tumors in different body organs. The mitotic spindle is responsible for sharing the chromosomes
and the researchers at the university believe that the mesh is needed to give structural support.
and cells had trouble sharing chromosomes during division. According to Emma Smith, Ph d.,from Cancer Research UK, his early research provides the first glimpse of a structure that helps share out a cell's chromosomes correctly
when it divides, and it might be a crucial insight into why this process becomes faulty in cancer
Techniques, such as electron microscopy, allowed scientists to identify nucleosomes, the first and most basic level of chromosome organisation.
#New cell division mechanism discovered (Nanowerk News) Canadian and British researchers have discovered that chromosomes play an active role in animal cell division.
Their findings were published today in Nature("Kinetochore-localized PP1SDS22 couples chromosome segregation to polar relaxation").
and it was unknown until now that chromosomes could play an active role at this step in cytokinesis.
the separation of chromosomes followed by splitting of the cell into two new daughter cells by cytokinesis."
called microtubules, were involved in pulling chromosomes to opposite poles of the cell during the division process.
At this time, microtubules physically separate the chromosomes via their central kinetochores while other microtubules signal to the cortex of the cell where its equator is, i e.,
it was believed that the chromosomes only played a passive role: that they were pulled by the microtubules
Chromosomes active role Initially working with the cells of fruit flies using powerful genetic tools and sophisticated microscopy,
the research team discovered that chromosomes emit signals that influence the cortex of the cell to reinforce microtubule action.
"When chromosomes are segregated, they approach the membrane at the poles of the cell, and thanks to this enzymes actions, this contributes to the softening of the polar membrane,
and protect genetic material in chromosomes, are highly stable proteins in non-dividing cells like nerve cells.
and it was unknown until now that chromosomes could play an active role in cell division. In animal cells, division involves mitosis,
the separation of chromosomes followed by splitting of the cell into two new daughter cells by cytokinesis. ivision is a complex and robust process that is generally performed flawlessly,
Working with fruit fly cells, Dr Hickson and co-authors discovered that chromosomes emit signals that influence the cortex of the cell to reinforce microtubule action.
Dr Hickson said. hen chromosomes are segregated, they approach the membrane at the poles of the cell,
TERT stabilizes chromosomes by elongating the protective element at the end of each chromosome in a cell. Scientists have discovered that cells harboring these mutations aberrantly increase TERT expression,
#New Cell division Mechanism Discovered Researchers have discovered that chromosomes play an active role in animal cell division.
and it was unknown until now that chromosomes could play an active role at this step in cytokinesis.
the separation of chromosomes followed by splitting of the cell into two new daughter cells by cytokinesis."
called microtubules, were involved in pulling chromosomes to opposite poles of the cell during the division process. t this time,
microtubules physically separate the chromosomes via their central kinetochores while other microtubules signal to the cortex of the cell where its equator is, i e.,
it was believed that the chromosomes only played a passive role: that they were pulled by the microtubules
the research team discovered that chromosomes emit signals that influence the cortex of the cell to reinforce microtubule action.
"When chromosomes are segregated, they approach the membrane at the poles of the cell, and thanks to this enzyme actions, this contributes to the softening of the polar membrane,
PP1DS22 couples chromosome segregation to polar relaxationin Nature on July 13, 2015. http://dx. doi. org/10.1038/nature14496
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