Researchers could use this novel "on-off switch" to control cell growth or death, grow new tissue or deliver doses of medication directly to diseased cells, said Tucker, an assistant research professor in the biology department at Duke.
She and colleagues created the switch by genetically inserting two proteins from a mustard plant, Arabidopsis thaliana, into yeast cells, kidney cells and cultured rodent brain tissue. The two proteins interact under light to provide the control over cell functions.
The switch is similar to one described last year where researchers genetically inserted a different light-receptive plant protein and its interacting protein partner from Arabidopsis into mammalian cells. In response to red light, these proteins interacted to cause mammalian cells to change shape, moving in the direction of the light.
Tucker's switch uses Arabidopsis proteins that respond to blue light. Unlike the red-light activated proteins, which need an added cofactor, a chemical that is required for the light response, the blue-light switch doesn't need any additional chemicals to work because it uses a cofactor that naturally exists in non-plant organisms.
"It's hard to deliver a chemical to a fly or to individual cells. This new approach, with one of the molecules already in the mammalian or yeast cells, makes building a light-controlled switch a lot easier," Tucker said. Her team describes the switch in the Oct. 31 Nature Methods.
To test the switch, the team fused one of the light-sensitive Arabidopsis proteins to a red fluorescent protein and the other to a green fluorescent protein, which was in turn attached to the cell membrane. When the researchers flashed blue light on the cell, the plant proteins interacted, causing the red fluorescent protein to rapidly move to the cell membrane, which then glowed yellow due to the merging of the red and green fluorescing proteins. The team found that this interaction was reversible and could be triggered repeatedly with light exposure.
The switch is one among several that have been designed to give researchers better control of different functions of the cell. The next step in developing the switch will be to make the interacting proteins more effective, Tucker said. The approach is expected to be applicable not only for studies in cultured cells and yeast, but also worms, fruit flies, mice and other model organisms. Eventually this method could allow researchers to test how cells in a tissue affect neighboring cells in a tissue, to guide axon growth in neurons to repair brain tissue, or even to kill cancer cells.
Tucker's new approach will be a "major boon" to those who wish to apply light activation to their own experimental systems, said Klaus Hahn, a pharmacologist at the University of North Carolina at Chapel Hill, whose lab reported on another blue-light responsive protein to control movement of mammalian cells last year.
Hahn said the "elegant work will likely see broad use, in many fields and for applications that will surprise us," and it is already going to be applied to important areas of research, such as control of gene expression.
Ashley Yeager | EurekAlert!
Two Group A Streptococcus genes linked to 'flesh-eating' bacterial infections
25.09.2017 | University of Maryland
Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden
At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.
Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
25.09.2017 | Power and Electrical Engineering
25.09.2017 | Health and Medicine
25.09.2017 | Physics and Astronomy