If you want to use the MNE Matlab toolbox on a regular basis, you should add the line
run /imaging/local/linux/mne_2.6.0/mne/matlab/toolbox/mne_setup_toolbox.m
to your startup.m file.
If you run mne_setup_2.6.0 before starting Matlab, it will automatically add the paths to the MNE tools.