Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Proteins find their way with address label and guide

Most newly produced proteins in a cell need to be transported to the proper place before they can be put to work. For proteins to find their way, they have a built-in signal linked to them, a kind of address label. Moreover, they are helped by a particle that guides them to the cell membrane. In a new study published in the journal Nature Structural and Molecular Biology, researchers at Umeå University in Sweden show how this interaction works.

Calculations indicate that each human cell contains roughly a billion protein molecules. In other words, it's crowded inside the cell, and order must be maintained. What's more, newly generated proteins often need to be transported from the place they were produced to the place they are to perform their tasks.

These proteins have a kind of address label, a signal sequence, that specifies what place inside or outside the cell they need to be transported to. This transport must function flawlessly if order is to be maintained in the cell, but also for the cell to be able to communicate with its surroundings. If a protein winds up in the wrong place, it can lead to serious disorders like cystic fibrosis.

The capacity to transport proteins in most cases is directly linked to the function of the SRP, the signal-recognizing particle. The SRP binds to the signal sequence and guides it and the attached protein to the cell membrane. A key question for these researchers has been how the interaction between the signal sequence and SRP works in detail.

The Umeå scientists have managed to create a detailed picture of the first step in this protein transport by studying a complex of a signal sequence that is bound to the SRP. The technology they used is called x-ray crystallography. The group has shown the basic structure of the SRP in several previous studies SRP. Thanks to these studies, they were now able to directly compare the SRP structure with and without the guiding signal sequence.

”The structural changes were considerably greater than what was previously predicted. They provide us with detailed explanations of what role SRPs play in protein transport. These structural specifications can also serve as a model of how SRPs function at various levels during protein transport," explains Elisabeth Sauer-Eriksson, professor at the Department of Chemistry.

Now these researchers are moving on to try to investigate the next transport mechanism. For instance, they want to answer questions about what prompts the bound signal sequence to let go of the SRP and how the signal sequence, and the protein it is attached to, can make its way through the membrane.

The scientists who carried out the study are part of Umeå University's strong research environment "biological chemistry" and the Umeå Centre for Microbial Research, UCMR. Funding for the research project is provided by the Swedish Research Council, UCMR, and the Kempe Foundations.

About SRP
SRP is a ribonucleotide protein complex. SRP is highly conserved in nature and exists in all living organisms, which indicates that it plays a fundamental role in the structure and function of the cell.

Original title: Structural basis of signal-sequence recognition by the signal recognition particle

Authors: Tobias Hainzl, Shenghua Huang, Gitte Meriläinen, Kristoffer Brännström, and Elisabeth Sauer-Eriksson

For further information, please contact:
Tobias Hainzl Telephone: +46 (0)90-786 5924 E-mail:
Elisabeth Sauer-Eriksson Telephone: +46 (0)90-786 5923 Mobile phone: +46 (0)70-6335320 E-mail:

Karin Wikman | idw
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>