UC Davis study finds brain cell regulator is volume control, not on/...( amounts of a protein in different sampl...)

amounts of a protein in different samples can be difficult. SILAC allows scientists to add additional atomic weight to one sample so that two different samples can be analyzed in a given run, allowing for precise measurements of quantity. The 'mass tag' separates the two samples--the experimental and control--on the mass spectrometry read out.

Using this technique, postdoctoral fellow Kang-Sik Park revealed 16 sites where the protein is modified by the cell by via addition of a phosphate group. Further study--in which each of the sites is removed to reveal its role in modulation-- followed by careful biophysical analyses of channel function by postdoctoral fellow Durga Mohapatra, revealed that seven of these sites were involved in the regulation of neuronal activity. Since each site can be regulated independently on the four channel subunits, the neuron can generate a huge (>1018) number of possible forms of the channel.

Using this mechanism, Kv2.1 channels are quickly modified, even mimicking the activity of other potassium ion channels. "The beauty of doing it with a single protein is that it is already there and can change in a matter of minutes. It would take hours for the cell to produce an entirely different potassium channel," Trimmer explained.

Based on these results, Trimmer and his colleagues hypothesize that parts of the Kv2.1 channel protein interact in ways that make it either easier or harder for it to change from closed to open. The protein, they believe, can exist in either loose states that require low amounts of energy, or voltage, to change from one state to another or a locked-down state that requires lots of energy (high voltage) to open or close. The number and position of phosphate molecules are what determine the amount of voltage required to open the channel.

The next step will be to determine how brain neurons regulate the addition and removal of phosphates at individual sites on the Kv2.1 protei
'"/>

Contact: Carole Gan
carole.gan@ucdmc.ucdavis.edu
916-734-9047
University of California, Davis - Health System
17-Aug-2006

Page: 1 2 3 4
Related biology news :

1. UC Davis is partner in new $125 million federal bioenergy research center
2. UC Davis study finds high arsenic levels in herbal kelp supplements
3. UC Davis wins new national center for avian flu research
4. UC Davis researchers use heated nanoprobes to destroy breast cancer cells in mice
5. UC Davis researchers discover key to bodys ability to detect subtle temperature changes
6. APS names UC Davis professor Bodil Schmidt-Nielsen Distinguished Mentor and Scientist
7. UC Davis scientists groundbreaking research: Mate-attracting chemicals
8. UC Davis breast cancer researchers report new insights into ductal carcinoma in situ
9. British cattle give TB to badgers, finds UC Davis expert
10. UC Davis study finds distinct genetic profiles
11. UC Davis researchers move biotechnology closer to replacing electronic pacemakers