Menu
Scientific revolution
Water Flowing On Mars, NASA Spacecraft Data Suggest

Light Shed On South Pole Dinosaurs

Why Plant 'Clones' Aren't Identical

Puffins 'Scout Out' Best Migration Route

New Conducting Properties Discovered in Bacteria-Produced Wires

Researchers Unravel the Magic of Flocks of Starlings

'Paranoia' About Rivals Alters Insect Mating Behavior

Billion-Year-Old Piece of North America Traced Back to Antarctica

You Can Count On This: Math Ability Is Inborn, New Research Suggests

Scientist Develops Virus That Targets HIV: Using a Virus to Kill a Virus

DNA Building Blocks Can Be Made in Space, NASA Evidence Suggests

Polar Dinosaur Tracks Open New Trail to Past

New Eruption Discovered at Undersea Volcano, After Successfully Forecasting the Event

Study Builds On Plausible Scenario for Origin of Life On Earth

Scientists Have New Help Finding Their Way Around Brain's Nooks and Crannies

Astronomy: A Spectacular Spiral in Leo

Hydrogen-Powered Symbiotic Bacteria Found in Deep-Sea Hydrothermal Vent Mussels

Deep Recycling in Earth Faster Than Thought

Engineers Reverse E. Coli Metabolism for Quick Production of Fuels, Chemicals

Genetically Modified 'Serial Killer' T-Cells Obliterate Tumors in Leukemia Patients

Biodiversity Key to Earth's Life-Support Functions in a Changing World

Darkest Known Exoplanet: Alien World Is Blacker Than Coal

Arctic Ice Melt Could Pause for Several Years, Then Resume Again

Like Humans, Chimps Are Born With Immature Forebrains

Decade-Long Study Reveals Recurring Patterns of Viruses in the Open Ocean

Key Mechanism That Regulates Shape and Growth of Plants Discovered
UBC researchers have discovered a key mechanism that -- much like a construction site foreperson -- controls the direction of plant growth as well as the physical properties of the biopolymers that plants produce. The finding is a major clue in a 50-year-long quest to explain how plants coordinate the behaviour of millions of cells as they grow upward to compete for light, penetrate soil to obtain nutrients and water, and even open petals to flower.

"We've known for decades that structures in plants called microtubules act as scaffolding to define the direction of cell expansion," says Professor Geoffrey Wasteneys, a UBC botanist and Canada Research Chair in Plant Cell Biology.

"These are tiny multipurpose cylinders that grow, shrink and self-organize to transport cargo, capture and position large structures such as chromosomes, and establish the shape of cells. But we haven't been able to determine how these tiny microtubules are organized into scaffolds in the first place."

An interdisciplinary team of plant cell biologists and mathematicians led by Wasteneys discovered that the inherent geometry of the cell itself plays an important role in the self-organization of microtubules into parallel arrays that guide cell growth and division. They also identified that a protein called CLASP plays a key role as a foreperson, modulating the geometric constraints of the cell.

Their findings will be published in the August 16 issue of the journal Nature Communications.

The research team used a specialized microscope that collects 3D images of plant components genetically engineered to fluoresce when irradiated with specially filtered light. They observed a striking difference in the way microtubules were arranged in normal plants compared to those of a dwarf mutant that fails to produce CLASP.

"Paradoxically, the microtubules appeared to be better organized in the severely stunted mutant plants than they were in the non-mutant plants," says Chris Ambrose, the post-doctoral fellow in Wasteneys' lab whose observations led to the discovery. "By examining how microtubules behave at the sharp edges between adjacent cell faces, we noticed that in the mutant, microtubules would grow into the edges and then undergo catastrophic disassembly. In the non-mutant plants containing the CLASP protein, microtubules would easily bend through 90 degrees and continue growing on the adjacent cell face upon encountering an edge."

Ambrose and Wasteneys then joined forces with UBC mathematicians Eric Cytrynbaum and Jun Allard to run three-dimensional computer simulations to test the ideas that emerged from imaging the living plant cells.

The researchers found that the simulations, which typically take about a day to run on a super computer, closely recapitulated the microtubule patterns observed in living cells.

"Simulation after simulation showed us that microtubules would form parallel arrays in the same patterns seen in living cells," says Allard, now a post-doctoral researcher at the University of California, Davis. "We confirmed that the self-organization depends on the extrinsic cues from the cellular geometry, and that the presence of the CLASP protein along select edges modified the pattern dramatically."

The finding may also be relevant to the burgeoning interest in stem cell biology in the biomedical research field. "Microtubules and the CLASP protein are common to all cell types in plants animals, fungi and many unicellular organisms," says Wasteneys. "So what we find out about their behaviour in plant cells is relevant to understanding their function in cells types as diverse as neurons and disease-causing protozoans."

The research was funded by the Natural Sciences and Engineering Research Council of Canada, the Canadian Institutes of Health Research, and the Canada Foundation for Innovation.

Для печати
click here

Polar Ice Caps Can Recover from Warmer Climate-Induced Melting, Study Shows

Sniffer Dogs Can Be Used to Detect Lung Cancer, Research Suggests

Further, Faster, Higher: Wildlife Responds Increasingly Rapidly to Climate Change

Simple Way to Grow Muscle Tissue With Real Muscle Structure

Parasite Uses the Power of Attraction to Trick Rats Into Becoming Cat Food

Growth of Cities Endangers Global Environment, According to New Analysis

Common Cause of All Forms of Amyotrophic Lateral Sclerosis (ALS) Discovered

Oldest Fossils On Earth Discovered

Plants and Fungi Play the 'Underground Market'

Galaxies Are Running out of Gas: Why the Lights Are Going out in the Universe

Antennas in Your Clothes? New Design Could Pave the Way

Astronomers Find Ice and Possibly Methane On Snow White, a Distant Dwarf Planet

Yeast's Epic Journey 500 Years Ago Gave Rise to Lager Beer


Menu
Smart Skin: Electronics That Stick and Stretch Like a Temporary Tattoo

Supernovae Parents Found: Clear Signatures of Gas Outflows from Stellar Ancestors

Hidden Soil Fungus, Now Revealed, Is in a Class All Its Own

Effortless Sailing With Fluid Flow Cloak

Research Reveals Genetic Link to Human Intelligence

Hidden Baja Undersea Park Is the World's Most Robust Marine Reserve

Searching for Spin Liquids: Much-Sought Exotic Quantum State of Matter Can Exist

How Butterflies Copy Their Neighbors to Fool Birds

Increased Tropical Forest Growth Could Release Carbon from the Soil

Fruit Bats Navigate With Internal Maps: Scientists Fit Bats With World's Smallest GPS Devices

Rapid Evolution Within Single Crop-Growing Season Increases Insect Pest Numbers

E. Coli, Salmonella May Lurk in Unwashable Places in Produce

Biologists Confirm Sunflower Domesticated in Eastern North America

Oldest Evidence of Nails in Modern Primates

Breathing New Life Into Earth: Evidence of Early Oxygen in the Oceans of Our Planet

Key Mechanism That Regulates Shape and Growth of Plants Discovered

Speaking and Understanding Speech Share the Same Parts of the Brain

Quantum Optical Link Sets New Time Records

It's a Small World, After All: Earth Is Not Expanding, NASA Research Confirms

Honeycomb Carbon Crystals Possibly Detected in Space

AIDS Researchers Isolate New Potent and Broadly Effective Antibodies Against HIV

Getting Inside the Mind (and Up the Nose) of Our Ancient Ancestors

Physicists Undo the 'Coffee Ring Effect'

Moon Younger Than Previously Thought, Analysis of Lunar Rock Reveals

Human Pathogen Killing Corals in the Florida Keys