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.
#'Chromosome shattering'seen in plants, cancer Plants can undergo the same extreme'chromosome shattering'seen in some human cancers and developmental syndromes,
UC Davis researchers have found. Chromosome shattering, or'chromothripsis,'has until now only been seen in animal cells.
A paper on the work is published in the online journal elife. The process could be applied in plant breeding as a way to create haploid plants with genetic material from only one parent,
it might also allow cancer researchers to use the laboratory plant Arabidopsis as a model to study chromosome behavior in cancer.
Chromothripsis involves slicing chromosomes into apparently random pieces, and reassembling it like a broken vase,
which chromosomes are moved and allocated to daughter cells during cell division. They discovered that when a variant of the model plant Arabidopsis with weakened centromeres is crossed to a plant with normal centromeres,
the cut-and-reassembly process leading to'shattered chromosomes
#Single protein causes Parkinson's disease and multiple system atrophy Typical of neurodegenerative disorders is disrupted the communication between brain cells together with a loss of cells in specific brain regions.
Bacolla is a research associate in the Vasquez Lab.'What we found in our study was that the sites of chromosome breaks are not random along the DNA double helix;
built by the short inverted repeats, mark the spots for chromosome breaks, mutations, and potentially initiate cancer development.'
and chromosome translocations is a novel and significant aspect of NCI grant supported studies on mechanisms of genomic instability.
Does this really occur now in the context of chromosomes in living organisms? Is it tissue specific?
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:"
"Problems 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's 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,
the structures that protect the chromosomes, are at the origin of pulmonary fibrosis. This is the first time that telomere damage has been identified as a cause of the disease.
or when cells with unreplicated DNA rush into cell division prematurely to produce an abnormal number of chromosomes in a cell, a condition called aneuploidy.
#How to make chromosomes from DNA Researchers at the University of Tokyo have discovered a long-overlooked process important for converting a long, string-like DNA molecule into a chromosome.
This function proved to be a prerequisite for making chromosomes from DNA. DNA molecules are long,
in a cell, are packed tightly into structures called chromosomes. Formation of chromosomes in a dividing cell is required for faithful transmission of information in DNA to daughter cells.
The condensin complex is known to play an essential role in assembling chromosomes, but it remains unknown how condensin is involved in folding of DNA molecules.
Researchers at the University of Tokyo, including Assistant professor Takashi Sutani, Professor Katsuhiko Shirahige (Institute of Molecular and Cellular Biosciences) and Ph d student Toyonori Sakata (Graduate school of Agricultural and Life sciences), isolated from cells
They also discovered that chromosome segregation defects in mutant cells that showed lowered levels of condensin function were rescued largely by transcription inhibition.
that ssdna is detrimental to assembling chromosomes, and that condensin restores unwound ssdna segments to double-stranded DNA. t was believed widely that unwound DNA segments return spontaneously to canonical double-helical DNA,
It has demonstrated also for the first time that the presence of ssdna impedes chromosome organization, providing insight into the mechanism of chromosome formation,
says Assistant professor Sutani u
#Discovery: cells unwillingly help adenoviruses Various viruses claim many lives every day and cause other nonlethal infections that can lead to serious complications.
when our chromosomes break and are said misrepaired Durocher. his work teaches us that the location of the break within the cell nucleus has a big impact on the efficiency of repair. he implications of the research could extend to a large number of developmental
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