Body movement, from the muscles in your arms to the neurons transporting those signals to your brain, relies on a massive collection of proteins called molecular motors.

Fundamentally, molecular motors are proteins that convert chemical energy into mechanical movement, and have different functions depending on their task. However, because they are so small, the exact mechanisms by which these molecules coordinate with each other is poorly understood.

Publishing in Science Advances, Kyoto University’s School of Engineering has found that two types of kinesin molecular motors have different properties of coordination. Collaborating with the National Institute of Information and Communications Technology, or NICT, the findings were made possible thanks to a new tool the team developed that parks individual motors on platforms thousands of times smaller than a single cell.

“Kinesin is a motor protein that is involved in actions such as cell division, muscle contractions, and flagella movement. They move along these long protein filaments called microtubules,” explains first author Taikopaul Kaneko. “In the body, kinesins work as a team to transport large molecules inside a cell, or allow the cell itself to move.”

To observe the coordination closely, the team constructed a device consisting of an array of gold nano-pillars 50 nanometers in diameter and spaced 200 to 1000 nanometers apart. For reference, a skin cell is about 30 micrometers, or 30,000 nanometers, in diameter.

“We then combined this array with self-assembled monolayers, or SAM, that immobilized a single kinesin molecule on each nano-pillar,” continues Kaneko. “This ‘nano-patterning’ method of motor proteins gives us control of the number and spacing of kinesins, allowing us to accurately calculate how they transport microtubules.”

The team evaluated two kinesins: kinesin-1 and kinesin-14, which are involved in intercellular transport and cell division, respectively. Their results showed that in the case of kinesin-1, neither the number nor spacing of the molecules change the transport velocity of microtubules.

In contrast, kinesin-14 decreased transport velocity as the number of motors on a filament increased, but increased as the spacing of the motors increased. The results indicate that while kinesin-1 molecules work independently, kinesin-14 interacts with each other to tune the speed of transport.

Ryuji Yokokawa who led the team was surprised by the results, “Before we started this study, we thought that more motors led to faster transport and more force. But like most things in biology, it’s rarely that simple.”

The team will be using their new nano-patterning method to study the mechanics of other kinesins and different molecular motors.

“Humans have over 40 kinesins along with two other types of molecular motors called myosin and dynein. We can even modify our array to study how these motors act in a density gradient. Our results and this new tool are sure to expand our understanding of the various basic cellular processes fundamental to all life,” concludes Yokokawa.

Source: A new ‘molecular nano-patterning’ technique reveals that some molecular motors coordinate differently

Rather than directions going one-way from DNA to RNA to proteins, the latest study shows that RNA itself modulates how DNA is transcribed—using a chemical process that is increasingly apparent to be vital to biology. The discovery has significant implications for our understanding of human disease and drug design.

[…]

The picture many of us remember learning in school is an orderly progression: DNA is transcribed into RNA, which then makes proteins that carry out the actual work of living cells. But it turns out there are a lot of wrinkles.

He’s team found that the molecules called messenger RNA, previously known as simple couriers that carry instructions from DNA to proteins, were actually making their own impacts on protein production. This is done by a reversible chemical reaction called methylation; He’s key breakthrough was showing that this methylation was reversible. It wasn’t a one-time, one-way transaction; it could be erased and reversed.

“That discovery launched us into a modern era of RNA modification research, which has really exploded in the last few years,” said He. “This is how so much of gene expression is critically affected. It impacts a wide range of biological processes—learning and memory, circadian rhythms, even something so fundamental as how a cell differentiates itself into, say, a blood cell versus a neuron.”

[…]

they began to see that messenger RNA methylation could not fully explain everything they observed.

This was mirrored in other experiments. “The data coming out of the community was saying there’s something else out there, something extremely important that we’re missing—that critically impacts many early development events, as well as human diseases such as cancer,” he said.

He’s team discovered that a group of RNAs called chromosome-associated regulatory RNAs, or carRNAs, was using the same methylation process, but these RNAs do not code proteins and are not directly involved in protein translation. Instead, they controlled how DNA itself was stored and transcribed.

“This has major implications in basic biology,” He said. “It directly affects gene transcriptions, and not just a few of them. It could induce global chromatin change and affects transcription of 6,000 genes in the cell line we studied.”

He sees major implications in biology, especially in human health—everything from identifying the genetic basis of disease to better treating patients.

“There are several biotech companies actively developing small molecule inhibitors of RNA methylation, but right now, even if we successfully develop therapies, we don’t have a full mechanical picture for what’s going on,” he said. “This provides an enormous opportunity to help guide disease indication for testing inhibitors and suggest new opportunities for pharmaceuticals.”

Source: Surprise discovery shakes up our understanding of gene expression

A new type of immune cell which kills most cancers has been discovered by accident by British scientists, in a finding which could herald a major breakthrough in treatment.

Researchers at Cardiff University were analysing blood from a bank in Wales, looking for immune cells that could fight bacteria, when they found an entirely new type of T-cell.

That new immune cell carries a never-before-seen receptor which acts like a grappling hook, latching on to most human cancers, while ignoring healthy cells.

In laboratory studies, immune cells equipped with the new receptor were shown to kill lung, skin, blood, colon, breast, bone, prostate, ovarian, kidney and cervical cancer.

Professor Andrew Sewell, lead author on the study and an expert in T-cells from Cardiff University’s School of Medicine, said it was “highly unusual” to find a cell that had broad cancer-fighting therapies, and raised the prospect of a universal therapy.

“This was a serendipitous finding, nobody knew this cell existed,” Prof Sewell told The Telegraph.

“Our finding raises the prospect of a ‘one-size-fits-all’ cancer treatment, a single type of T-cell that could be capable of destroying many different types of cancers across the population. Previously nobody believed this could be possible.”

[…]

the new cell attaches to a molecule on cancer cells called MR1, which does not vary in humans.

It means that not only would the treatment work for most cancers, but it could be shared between people, raising the possibility that banks of the special immune cells could be created for instant ‘off-the-shelf’ treatment in future.

When researchers injected the new immune cells into mice bearing human cancer and with a human immune system, they found ‘encouraging’ cancer-clearing results.

And they showed that T-cells of skin cancer patients, which were modified to express the new receptor, could destroy not only the patient’s own cancer cells, but also other patients’ cancer cells in the laboratory.

[…]

Professor Awen Gallimore, of the University’s division of infection and immunity and cancer immunology lead for the Wales Cancer Research Centre, added: “If this transformative new finding holds up, it will lay the foundation for a ‘universal’ T-cell medicine, mitigating against the tremendous costs associated with the identification, generation and manufacture of personalised T-cells.

“This is truly exciting and potentially a great step forward for the accessibility of cancer immunotherapy.”

Commenting on the study, Daniel Davis, Professor of Immunology at the University of Manchester, said it was an exciting discovery which opened the door to cellular therapies being used for more people.

“We are in the midst of a medical revolution harnessing the power of the immune system to tackle cancer.  But not everyone responds to the current therapies and there can be harmful side-effects.

“The team have convincingly shown that, in a lab dish, this type of immune cell reacts against a range of different cancer cells.

“We still need to understand exactly how it recognises and kills cancer cells, while not responding to normal healthy cells.”

The research was published in the journal Nature Immunology.

Source: Immune cell which kills most cancers discovered by accident by British scientists in major breakthrough 

River flow is reduced in areas where forests have been planted and does not recover over time, a new study has shown. Rivers in some regions can completely disappear within a decade. This highlights the need to consider the impact on regional water availability, as well as the wider climate benefit, of tree-planting plans.

“Reforestation is an important part of tackling climate change, but we need to carefully consider the best places for it. In some places, changes to water availability will completely change the local cost-benefits of tree-planting programmes,” said Laura Bentley, a plant scientist in the University of Cambridge Conservation Research Institute, and first author of the report.

Planting large areas of trees has been suggested as one of the best ways of reducing atmospheric carbon dioxide levels, since trees absorb and store this greenhouse gas as they grow. While it has long been known that planting trees reduces the amount of water flowing into nearby rivers, there has previously been no understanding of how this effect changes as forests age.

The study looked at 43 sites across the world where forests have been established, and used river flow as a measure of water availability in the region. It found that within five years of planting trees, river flow had reduced by an average of 25%. By 25 years, rivers had gone down by an average of 40% and in a few cases had dried up entirely. The biggest percentage reductions in water availability were in regions in Australia and South Africa.

“River flow does not recover after planting trees, even after many years, once disturbances in the catchment and the effects of climate are accounted for,” said Professor David Coomes, Director of the University of Cambridge Conservation Research Institute, who led the study.

Published in the journal Global Change Biology, the research showed that the type of land where trees are planted determines the degree of impact they have on local water availability. Trees planted on natural grassland where the soil is healthy decrease river flow significantly. On land previously degraded by agriculture, establishing forest helps to repair the soil so it can hold more water and decreases nearby river flow by a lesser amount.

Counterintuitively, the effect of trees on river flow is smaller in drier years than wetter ones. When trees are drought-stressed they close the pores on their leaves to conserve water, and as a result draw up less water from the soil. In wet weather the trees use more water from the soil, and also catch the rainwater in their leaves.

“Climate change will affect water availability around the world,” said Bentley. “By studying how forestation affects water availability, we can work to minimise any local consequences for people and the environment.”

Source: Local water availability is permanently reduced after planting forests

A little over a year ago, Caltech’s Lihong Wang developed the world’s fastest camera, a device capable of taking 10 trillion pictures per second. It is so fast that it can even capture light traveling in slow motion.

But sometimes just being quick is not enough. Indeed, not even the fastest camera can take pictures of things it cannot see. To that end, Wang, Bren Professor of Medical Engineering and Electrical Engineering, has developed a new camera that can take up to 1 trillion pictures per second of transparent objects. A paper about the camera appears in the January 17 issue of the journal Science Advances.

The camera technology, which Wang calls phase-sensitive compressed ultrafast photography (pCUP), can take video not just of transparent objects but also of more ephemeral things like shockwaves and possibly even of the signals that travel through neurons.

Wang explains that his new imaging system combines the high-speed photography system he previously developed with an old technology, phase-contrast microscopy, that was designed to allow better imaging of objects that are mostly transparent such as cells, which are mostly water.

[…]

Wang says the technology, though still early in its development, may ultimately have uses in many fields, including physics, biology, or chemistry.

“As signals travel through neurons, there is a minute dilation of nerve fibers that we hope to see. If we have a network of neurons, maybe we can see their communication in real time,” Wang says. In addition, he says, because temperature is known to change phase contrast, the system “may be able to image how a flame front spreads in a combustion chamber.”

The paper describing pCUP is titled “Picosecond-resolution phase-sensitive imaging of transparent objects in a single shot.”

Source: Ultrafast camera takes 1 trillion frames per second of transparent objects and phenomena

A huge trash-collecting system designed to clean up plastic floating in the Pacific Ocean is finally picking up plastic, its inventor announced Wednesday.

The Netherlands-based nonprofit the Ocean Cleanup says its latest prototype was able to capture and hold debris ranging in size from huge, abandoned fishing gear, known as “ghost nets,” to tiny microplastics as small as 1 millimeter.

“Today, I am very proud to share with you that we are now catching plastics,” Ocean Cleanup founder and CEO Boyan Slat said at a news conference in Rotterdam.

The Ocean Cleanup system is a U-shaped barrier with a net-like skirt that hangs below the surface of the water. It moves with the current and collects faster moving plastics as they float by. Fish and other animals will be able to swim beneath it.

The new prototype added a parachute anchor to slow the system and increased the size of a cork line on top of the skirt to keep the plastic from washing over it.

The Ocean Cleanup’s System 001/B collects and holds plastic until a ship can collect it.

It’s been deployed in “The Great Pacific Garbage Patch” — a concentration of trash located between Hawaii and California that’s about double the size of Texas, or three times the size of France.

Ocean Cleanup plans to build a fleet of these devices, and predicts it will be able to reduce the size of the patch by half every five years.

Source: A floating device created to clean up plastic from the ocean is finally doing its job, organizers say – CNN