Tag Archives: chromosome

Wie bleibt genetisches Material während der Fortpflanzung intakt?

By Guest PostJuly 16, 2016Sciencealexander vogler, chromosome, dna doppelstrangbrueche, genetische information, marlene jagut, max perutz, structured illumination microscopy

MolekularbiologInnen erforschen Prozesse beim Ausschneiden und Einfügen von DNA

Eltern vererben ihre genetische Information in Form von Chromosomen. Diese sind jedoch nicht einfache Kopien, sondern ein Mosaik aus den beiden Chromosomenkopien, die sie selbst erhalten haben. Die Herstellung dieser Mosaike erfolgt durch einen Prozess des Ausschneidens und Einfügens von Chromosomenstücken. Wie solche Schnitte – auch Brüche genannt – in unserem genetischen Material repariert werden, untersuchen Verena Jantsch und ihr Team an den Max F. Perutz Laboratories der Universität Wien und der Medizinischen Universität Wien. Ihre Ergebnisse geben wichtige Einblicke in die Prozesse, die sicherstellen, dass unser genetisches Material intakt bleibt und so genetische Krankheiten und Krebsentstehung verhindern.

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Racism May Accelerate Aging in African American Men

By Guest PostJanuary 14, 2014Healthafrican american men, african americans, aging, anti black attitudes, biological age, biological level, biomarker, cellular level, chromosome, chronological age, david h chae, disease risk, gene h brody, indicator, leukocyte telomere length, physiological stress, racial discrimination, racism, sequences of dna, systemic aging, tear, telomere, university of maryland, wear

UMD-led study is first to link racism-related factors and cellular age

COLLEGE PARK, Md. – A new University of Maryland-led study reveals that racism may impact aging at the cellular level. Researchers found signs of accelerated aging in African American men who reported high levels of racial discrimination and who had internalized anti-Black attitudes. Findings from the study, which is the first to link racism-related factors and biological aging, are published in the American Journal of Preventive Medicine.

Racial disparities in health are well-documented, with African Americans having shorter life expectancy, and a greater likelihood of suffering from aging-related illnesses at younger ages compared to whites. Accelerated aging at the biological level may be one mechanism linking racism and disease risk. (more…)

UMass Amherst Cell Biologists Show Molecular Forces Are Key to Proper Cell Division

By Guest PostJanuary 24, 2013Scienceanna ye, cell biologist, cell death, cell division, chromosome, chromosome microtubule interactions, culture cell, daughter cell, detection pathway, error rate, flawless cell, fluorescently tag chromosomes, fruit fly tissue, function, human disease, interaction error, kinetochore microtubule interaction, kinetochore regulator, kinetochores, massachusetts amherst, microtubule filament, mitotic spindle, modulate, molecular engine, molecular glue, molecular surveillance system, pef, polar ejection force, spindle, stuart cane, syntelic attachments, thomas maresca, university

AMHERST, Mass. – Studies led by cell biologist Thomas Maresca at the University of Massachusetts Amherst are revealing new details about a molecular surveillance system that helps detect and correct errors in cell division that can lead to cell death or human diseases. Findings are reported in the current issue of the Journal of Cell Biology.

The purpose of cell division is to evenly distribute the genome between two daughter cells. To achieve this, every chromosome must properly interact with a football-shaped structure called the spindle. However, interaction errors between the chromosomes and spindle during division are amazingly common, occurring in 86 to 90 percent of chromosomes, says Maresca, an expert in mitosis. (more…)

UCLA Bioengineers Discover Single Cancer Cell Can Produce Up To Five Daughter Cells

By Guest PostJuly 16, 2012Science3d mechanical environment, aneuploidy, biological process, cancer cell, cancer mitosis, chromosome, daughter cell, dino di carlo, Environment, invasive cancer, mammalian cell division, microfluidic device, microfluidic platform, mitosis, tumor environment, ucla, westbrook mcconnell weaver

Findings could aid researchers in understanding progression of disease

It’s well known in conventional biology that during the process of mammalian cell division, or mitosis, a mother cell divides equally into two daughter cells. But when it comes to cancer, say UCLA researchers, mother cells may be far more prolific.

Bioengineers at the UCLA Henry Samueli School of Engineering and Applied Science developed a platform to mechanically confine cells, simulating the in vivo three-dimensional environments in which they divide, and found that, upon confinement, cancer cells often split into three or more daughter cells.

“We hope that this platform will allow us to better understand how the 3-D mechanical environment may play a role in the progression of a benign tumor into a malignant tumor that kills,” said Dino Di Carlo, an associate professor of bioengineering at UCLA and principal investigator on the research. (more…)

Human Brain Evolution Tied to Partial Gene Copy That Blocks Original

By Guest PostMay 7, 2012Scienceafrican, brain development gene, chromosome, cortex, denisovans, embryology, evan eichler, evolutionary history, franck polleux, gene duplication, genus homo, homo sapiens, humans, hydatidiform mole, mammalian species, megan dennis, neanderthals, parent gene, peter sudmant, prehistoric human genome, primate, srgap2 gene family, university of washington, xander nuttle

A brain-development gene found exclusively in humans has an unusual evolutionary history and could contribute to what makes us distinctly human. Equally surprising, this is a partial gene created from an incomplete duplication of its “parent” gene in the prehistoric human genome.

Gene duplication is an important driving force in creating physical changes in living things during evolution, explained the researchers studying the SRGAP2 gene family. Drs. Megan Dennis and Xander Nuttle, in the Howard Hughes Medicine Institute research lab of Dr. Evan Eichler, University of Washington professor of genome sciences, co-authored the report on the findings. (more…)

Low Quality Genes May Cause Mutational Meltdown

By Guest PostApril 19, 2012Scienceaneil agrawal, chromosome, DNA, dna damage, drosophila melanogaster, eeb, environmental stress, evolutionary biologist, extinction, fruit fly, genetic deficiencies, high quality gene, low quality gene, mammal, mutation, nathaniel sharp, poor genetic quality, repairing dna, species, university of toronto

Deficiencies compound over time, researchers say

Evolutionary biologists at the University of Toronto have found that individuals with low-quality genes may produce offspring with even more inferior chromosomes, possibly leading to the extinction of certain species over generations.

Their study, published in Proceedings of the National Academy of Sciences, predicts that organisms with such genetic deficiencies could experience an increased number of mutations in their DNA, relative to individuals with high-quality genes. The research was done on fruit flies whose simple system replicates aspects of biology in more complex systems, so the findings could have implications for humans. (more…)

New Molecule Has Potential to Help Treat Genetic Diseases and HIV

By Guest PostFebruary 13, 2012Scienceamy rhoden smith, austin, base molecule, brent iverson, cells, chromosome, DNA, dna sequence, double helix, garen holman, georgetown, hiv, kenneth johnson, legos, maha zewail foote, molecule, naphthalenetetracarboxylic diimide, ndi, protease inhibitors, sequence of genes, southwestern university, spiral staircase, university of texas, viral dna

AUSTIN, Texas — Chemists at The University of Texas at Austin have created a molecule that’s so good at tangling itself inside the double helix of a DNA sequence that it can stay there for up to 16 days before the DNA liberates itself, much longer than any other molecule reported.

It’s an important step along the path to someday creating drugs that can go after rogue DNA directly. Such drugs would be revolutionary in the treatment of genetic diseases, cancer or retroviruses such as HIV, which incorporate viral DNA directly into the body’s DNA. (more…)

Ancient Humans Were Mixing it Up

By Guest PostSeptember 7, 2011Scienceafrica, archaic hominin forms, august woerner, central africa, chromosome, contemporary african populations, DNA, eurasia, fernando mendez, fossil, fossil specimens, genome, homo, homo sapiens, hybridization, jeffrey wall, joseph watkins, michael hammer, modern humans, molecular biology, morphologically diverged neighbors, neanderthal bones, neanderthals, sub saharan africans

*Anatomically modern humans interbred with more archaic hominin forms even before they migrated out of Africa, a UA-led team of researchers has found.*

It is now widely accepted that anatomically modern humans of the species Homo sapiens originated in Africa and eventually spread throughout the world. Ancient DNA recovered from fossil Neanderthal bones suggests they interbred with more archaic hominin forms once they had left their evolutionary cradle for the cooler climates of Eurasia, but whether they exchanged genetic material with other, now extinct archaic hominin varieties in Africa remained unclear.

In a paper published in the Proceedings of the National Academy of Sciences, or PNAS, a team led by Michael Hammer, an associate professor and research scientist with the UA’s Arizona Research Labs, provides evidence that anatomically modern humans were not so unique that they remained separate. (more…)