Notes, news, and information on human and general molecular biology. My particular interests lie in immunology, cancer biology, pathology, and human evolution. I have a weakness for cute animal pictures.
ANN:
Manga artist Hirohiko Araki has drawn the cover of volume 130’s issue 5 of the American biological journal Cell, at the request of two Japanese authors published in this issue. Dr. Mitsutoshi Setou and Dr. Hiroshi Ageta are part of a team that identified a protein named SCRAPPER that helps regulate synaptic activity in the nervous system. Among other potential benefits, the findings reported in the “Ubiquitin Ligase for Synaptic Tuning” article will aid research on Alzheimer’s disease and strokes.
According to the issue, Araki’s art depicts SCRAPPER as a purple humanoid “putting blue heart-shaped ubiquitins on the red RIM creatures.” Araki drew the illustration with the scientific direction of Drs. Setou and Ageta.
(via bekindplzrewind)
New form of cell division found
Researchers at the University of Wisconsin Carbone Cancer Center have discovered a new form of cell division in human cells.
They believe it serves as a natural back-up mechanism during faulty cell division, preventing some cells from going down a path that can lead to cancer.
“If we could promote this new form of cell division, which we call klerokinesis, we may be able to prevent some cancers from developing,” says lead researcher Dr. Mark Burkard, an assistant professor of hematology-oncology in the department of medicine at the UW School of Medicine and Public Health.
Burkard presented the finding on Monday, Dec. 17 at the annual meeting of the American Society for Cell Biology in San Francisco.
(View a short video of the process here)
There’s also a YouTube video for the same video here
(via infectiousdiseases)
Some cells found in the epidermis.
-bioljerk
Phase transition from liquid to rigid crystalline (gel) states of the cell membrane is affected primarily by a characteristic freezing point of the lipid molecules within the membrane. Other factors include:
- Shorter hydrocarbon tails: this reduces the possibility of interaction between other tails on the same or opposite monolayer.
- Unsaturated fat composition: unsaturated fats have cis double-bonds in the hydrocarbon tails, giving them a characteristic kink, which make individual molecules harder to pack close together so the monolayer is thinner and more flexible.
Homeoviscous adaption: some organisms are capable of adapting their membrane composition based on their environment in order to avoid the loss of membrane fluidity this may bring. The synthesis of saturated (at higher temperatures) and unsaturated lipids (at lower temperatures) is the most common, but other adaptions also occur. For example, protozoa found in the Antarctic also have very short hydrocarbon tails, making them harder to freeze.
There are 10^9 lipid molecules in the phospholipid bilayer of a single small animal cell.
Death Most Beautiful
by Thomas Deerinck and Mark Ellisman, NCMIR, UCSD
Programmed cell death ensures that our bodies contain just the right number of cells. This tightly regulated process removes damaged cells, shapes our organs and digits, and refines our immune systems. Here, multiphoton fluorescence imaging reveals an apoptotic HeLa cell (middle) amongst non-dying neighbors.
Researchers Develop Nanoparticle “Synthetic Virus” to Improve Drug Delivery to Targeted Cells
National Cancer Institute scientists have built fully synthetic self-assembling virus-like nanoparticles that fuse with cells like real viruses, Nature News Blog reports.
Viruses are extremely effective at targeting cells and delivering proteins into them. To mimic a virus, the team used amino acids to build a molecule that resembles a known protein that spans cell membranes.
The team previously described how these proteins self-assemble into spherical nanoparticles in solution. Now the team has gone further, showing that these nanoparticles can fuse with cells via receptors. By incorporating compounds into their nanoparticles that normally bind prostate tumor cells, their virus-mimic selectively targets these cells.
They can be used to encapsulate drugs, meaning that a synthetic virus-like particle could be created to target cancer cells and then deliver a chemotherapy payload precisely to the tumor.
(via ‘Virus-like’ nanoparticle built to target tumors | KurzweilAI)
Alcohol Byproduct Kills Blood’s Stem Cells
Scientists at the Medical Research Council (MRC) Laboratory of Molecular Biology have found that stem cells in the body’s “blood cell factory” – the bone marrow – are extremely sensitive to the main breakdown product of alcohol, which causes irreversible damage to their DNA.
New research in mice, published in Nature, shows that this damage is normally kept in check by two vital control mechanisms: an enzyme that mops up the toxic breakdown product (acetaldehyde) and a group of proteins that recognize and repair damaged DNA. Mice lacking both these protective mechanisms develop bone marrow failure, due to obliteration of their blood stem cells.
Read more: http://www.laboratoryequipment.com/news/2012/08/alcohol-byproduct-kills-blood%E2%80%99s-stem-cells
This primer on stem cells is intended for anyone who wishes to learn more about the biological properties of stem cells, the important questions about stem cells that are the focus of scientific research, and the potential use of stem cells in research and in treating disease. The primer includes information about stem cells derived from embryonic and non-embryonic tissues. Much of the information included here is about stem cells derived from human tissues, but some studies of animal-derived stem cells are also described.
The NIH developed this primer to help readers understand the answers to questions such as:
- What are stem cells?
- What are the different types of stem cells, and where do they come from?
- What is the potential for new medical treatments using stem cells?
- What research is needed to make such treatments a reality?
A nice introduction to stem cells.
pancreatic cancer cells
Bad Neighbourhood
A tumour isn’t simply a lump of cancer cells. Behaving like a rogue organ, it corrupts healthy cells nearby to create a dysfunctional neighbourhood that helps it thrive. Researchers are investigating how these ‘good cells gone bad’ help tumours to resist the toxic effects of chemotherapy. It might explain why some drugs that seem promising when used on isolated cancer cells, don’t work so well in animal tests or clinical trials. These pictures show cells from mouse breast tumours at different stages – pre-cancerous (top row), early cancer (middle) and advanced cancer (bottom) – treated with different amounts of a chemotherapy drug called doxorubicin. It kills all the different stage cancer cells (right column) in the lab but doesn’t work so well in advanced cancer in the whole animal. The ‘bad neighbourhood’ in the body must be helping the tumour to resist treatment.
Written by Kat Arney
—
- Mikala Egeblad
- Cold Spring Harbor Laboratory, USA
- Copyright Elsevier 2012
- Published in Cancer Cell, 21 (3), 488–503
When biology is taught, it can look very static.
It seems, on paper, that things in a cell follow a logical order; we can trace the path of carbohydrates, for example, through glycolysis and the citric acid cycle, the latter fueling the reduction of high-energy electron carriers to generate ATP through the churning of the electron transport chain’s proton pump. Proteins looked rigid, trapped in complex three-dimensional structures, and everything in the cell appears as neat little capsules within the cellular membrane: Organised. Logical. Functional.
Not so, say Alain Viel and Robert. A. Lue.
The Harvard University professors of Molecular and Cell Biology pioneered the BioVisions project - an aim to get Harvard undergraduates to understand the chaotic complexity of the cellular environment. To do this, they developed extraordinarily precise animations; a far cry from the typical narrative explanations in science documentaries, these are accurate down to the smallest protein subunit.
The ultimate goal of the BioVisions project can be summarised by ‘to see is to begin to understand.’ Biology is constantly innovating, and new and more powerful ways to communicate it are becoming increasingly necessary as the discipline becomes ever more microscopic. The very act of observing and recording data lies at the foundation of all the natural sciences - and molecular biology is no exception.
So sit back, relax, and take a tour of the mitochondria: The cell’s ATP pump. See what you can spot in the animation; ATP is the glowing orange molecule, for example, and ADP is the burnt orange one.
All video credit goes to Harvard University and the BioVisions project.
(via fyeahmedlab)
