Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bright and stable: New acid-tolerant green fluorescent protein for bioimaging

05.01.2018

Osaka University researchers develop new green fluorescent protein that can withstand low pH environment for imaging of acidic organelles

Visualizing cellular components and processes at the molecular level is important for understanding the basis of any biological activity. Fluorescent proteins (FPs) are one of the most useful tools for investigating intracellular molecular dynamics.


A schematic of development of Gamillus. Gene of the fluorescent protein was cloned from tentacles of flower hat jellyfish, and was engineered to improve the monomeric property and the brightness. (The flower hat jellyfish was provided by Mr. Kamoizumi in Kamo Aquarium, Yamagata, Japan.)

Credit: Kamo Aquarium and Osaka University

However, FPs have usage limitations for imaging in low pH environments, such as in acidic organelles, including endosomes, lysosomes, and plant vacuoles. In environments of pH less than 6, most FPs lose their brightness and stability due to their neutral pKa. pKa is the measure of acid strength; the smaller the pKa is, the more acidic the substance is.

"Although there are reports of several acid-tolerant green FPs (GFPs), most have serious drawbacks. Furthermore, there is a lack of acid-tolerant GFPs that are practically applicable to bioimaging," says Hajime Shinoda, lead author of an Osaka University study that aimed to design acid-tolerant monomeric GFP that is practically applicable to live-cell imaging in acidic organelles. "In the current study, we developed an acid-tolerant GFP. We called it Gamillus."

Gamillus is a GFP cloned from Olindias formosa (flower hat jellyfish) and exhibits superior acid tolerance (pKa=3.4) and nearly twice as much brightness compared with the reported GFPs. The fluorescence spectrum is constant between pH4.5 and 9.0, which falls between the intracellular range in most cell types.

X-ray crystallography (a technique used for determining the atomic and molecular structure of a crystal, in this case, a Gamillus crystal) and point mutagenesis suggest the acid tolerance of Gamillus is attributed to stabilization of deprotonation in its chemical structure. The findings were published in Cell Chemical Biology.

"The applicability of Gamillus as a molecular tag was shown by the correct localization pattern of Gamillus fusions in a variety of cellular structures, including ones that are difficult to target," corresponding author Takeharu Nagai says. "We believe Gamillus can be a powerful molecular tool for investigating unknown biological phenomena involving acidic organelles, such as autophagy."

Saori Obayashi | EurekAlert!

More articles from Life Sciences:

nachricht NIH scientists illuminate causes of hepatitis b virus-associated acute liver failure
14.11.2018 | NIH/National Institute of Allergy and Infectious Diseases

nachricht Fish recognize their prey by electric colors
13.11.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

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 Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

NIH scientists illuminate causes of hepatitis b virus-associated acute liver failure

14.11.2018 | Life Sciences

The unintended consequences of dams and reservoirs

14.11.2018 | Earth Sciences

NIH scientists combine technologies to view the retina in unprecedented detail

14.11.2018 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>