Ellen V. Kearns wrote:
>> Hi everyone,
>> I am thinking about Rainer Hedrich's model for malate regulation of the GCAC1,
> guard cell anion channel 1, and I wonder where the external malate is coming
> from. I understand that it comes from mesophyll cells, but why? Do they convert
> it from OAA and then export it to the substomatal cavity?
Is there really a need for an external source of malate??
A long time ago [groan] I challenged Bowling's malate 'switch'
hypothesis about a malate ion-trap in the subsidiary cells on the
grounds that 'isolated' guard cells were able to produce malate ...
Travis, A.J. and Mansfield, T.A. (1977) Studies of malate formation in
'isolated' guard cells, New Phytologist, 78, 541-546.
Dr. A.J.Travis, | mailto:ajt at rri.sari.ac.uk
Rowett Research Institute, | http://www.rri.sari.ac.uk/~ajt
Greenburn Road, Bucksburn, | phone:+44 (0)1224 712751
Aberdeen AB2 9SB, Scotland, UK. | fax:+44 (0)1224 716687