Even well-studied proteins can reveal surprises. University of Iowa scientists have discovered a new enzyme activity for the cystic fibrosis transmembrane conductance regulator (CFTR). CFTR is the protein that is defective in cystic fibrosis, a common life-threatening genetic disease that affects primarily the lungs and pancreas of young people. The discovery, which appeared in the Dec. 26, 2003 issue of Cell, helps solve a long-standing puzzle about how this important protein works.
CFTR forms a channel, or pore, in the membrane of airway cells. When the channel is open, the salt chloride flows through it from one side of the membrane to the other. It has been known for many years that CFTR channel opening requires a molecule called ATP and that CFTR has an enzymatic activity called ATPase that uses ATP. ATP is the energy currency of the cell and the ATPase reaction spends the energy of ATP to power enzyme activity. Because chloride flows passively through the CFTR channel, it has long seemed puzzling that the opening of CFTR would require the substantial energy of ATP. Moreover, energy from ATP is not required to fuel any other ion channel.
The UI study now reveals that CFTR can function as an adenylate kinase enzyme. Like an ATPase, the adenylate kinase reaction uses ATP. But in contrast to an ATPase, an adenylate kinase enzyme also uses a related molecule called AMP. Importantly, the adenylate kinase neither consumes nor produces energy, but it controls channel opening. The study also suggests that in normal cells it is this enzyme activity rather than the ATPase that opens the CFTR channel.
Jennifer Brown | EurekAlert!
Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel
Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
24.05.2017 | Event News
24.05.2017 | Information Technology
24.05.2017 | Awards Funding