Marker (kDa)

1
Supplemental Figure 1. Specific biotinylated
membrane protein profile was distinct from the
total protein profile from cultured hippocampal
neurons. Hippocampal primary culture neurons were
prepared from E18 Sprague Dawley embryos and
cultured for 10 d in B27NB media. Surface
proteins of the neurons were labeled with biotin,
and the cells were then harvested with lysis
buffer. Equal amount of proteins were separated
by 10 electrophoresis. A, Protein gel was
stained by Simply Blue SafeStain (Invitrogen)
according to the manufacturers instructions. B,
Proteins were transferred onto nitrocellulose
membrane and stained by streptavidin conjugated
with HRP (110,000 Chemicon). Please note that
the protein profiles after Simply Blue staining
or the HRP--streptavidin staining are quite
different. Only a subset of proteins exposed to
biotin on the neuronal surface were biotinylated.
The arrows indicate that two most abundant
proteins stained by Simply Blue were not
biotinylated. This experiment was repeated twice
(n 3).
Streptavidin-HRP
Marker (kDa)
Simply Blue
250
148
98
64
50
36
22
16
Supplemental Figure 1