Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Solving a case of intercellular entrapment

09.01.2015

UCSB's Reich Group uses lasers to spatially and temporally control the release of a tagged protein inside a cell

Optogenetics, which uses light to control cellular events, is poised to become an important technology in molecular biology and beyond. The Reich Group in UC Santa Barbara's Department of Chemistry and Biochemistry has made a major contribution to this emergent field by developing a light-activated nanocarrier that transports proteins into cells and releases them on command. The findings appear in the journal Molecular Pharmaceutics.


A hollow gold nanoshell with a modular nickel linking layer (upper left) exposed to a laser (800 nm) shows the cellular uptake and protein release.

Credit: UCSB

Using inorganic gold nanoshells and a near-infrared laser, UCSB biochemistry professor Norbert Reich and graduate student Demosthenes Morales demonstrate for the first time a method that affords both spatial and temporal control over protein delivery in cells.

"You can point the laser at cells where and when you want a particular protein to be turned on," Reich said. "And that means you can ask biological questions that you could never ask before because you're able to say I want this one cell to do this."

The researchers exploited the receptors on prostate cancer cells, which rely on the recognition of a C-end rule internalizing peptide that has been fused to the end of a green fluorescent protein. This peptide is very specific for the receptor and once the two meet, it actually takes in the protein-loaded nanoparticles and shepherds them into the cell via endocytosis, a process that brings large molecules into cells.

The team used a modular nickel linking layer on the surface of the nanoparticles that is able to support different kinds of proteins fused with a polyhistidine tag commonly found on proteins expressed in labs. "We want this to be applicable to any type of protein that has a polyhistidine tail," lead author Morales said, "so if you synthesize or grow proteins in a lab, you can easily load the protein onto our nanoparticles."

While the Reich Group's hollow gold nanoshells are effective carriers, transporting large biomolecules such as proteins into cells is only half the battle. In order for the protein to be effective once inside the cell, it must be released from the vesicle (endosome) holding it. The UCSB design enables that to happen.

When we excite these hollow gold nanoshells with light, the surface of the nanoparticle becomes somewhat hot," Morales said. "The light not only releases the cargo that's on the surface but also causes the formation of vapor bubbles, which expand and eventually pop the vesicle, allowing for endosome escape."

The Reich Group's construct is designed around the advantage of protein delivery's specificity. "The best thing about our platform is that it has a wide range of applicability," Morales noted. "Not only do we have the ability to target with a laser where and when we want to release our therapeutic, but we also leverage the fact that the protein itself is very specific. We have specificity in terms of time and we have specificity toward the target. This is why proteins are very fascinating as a potent therapeutic."

According to Reich, this technology has important implications for basic research. "Biologists are going to make use of this kind of technology but they aren't going to develop it," Reich said. "There are a few people on campus who could use this technology so we have a unique opportunity at UCSB to be the lead in interfacing between the developers and the users."

Julie Cohen | EurekAlert!
Further information:
http://www.ucsb.edu

More articles from Life Sciences:

nachricht Water world
20.11.2017 | Washington University in St. Louis

nachricht Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Water world

20.11.2017 | Life Sciences

Less is more to produce top-notch 2D materials

20.11.2017 | Materials Sciences

Carefully crafted light pulses control neuron activity

20.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>