O. Hermanson et al., CYTOPLASMIC CREB-ALPHA-LIKE ANTIGENS IN SPECIFIC REGIONS OF THE RAT-BRAIN, Biochemical and biophysical research communications, 225(1), 1996, pp. 256-262
We have investigated the expression of the alpha-region of CREB (amino
acids 88-101) in the rat brain. This region is encoded by a separate
exon and has been reported to enhance the transcriptional efficiency o
f CREB. Light microscopic immunohistochemistry showed labeled neurons
in several brain regions, such as the spinal cord, pontine reticular f
ormation, cerebellum, hypothalamus, hippocampus and olfactory cortex.
The labeling was exclusively cytoplasmic, and electron microscopy reve
aled that the CREB alpha-immunoreactivity was localized to the Golgi a
pparatus and axon terminals. Immunoblotting after SDS-PAGE showed spec
ifically detected proteins of 21 and 160 kD. We suggest that neuronal
CREB alpha-proteins represent alternatively spliced isoforms of CREB t
hat lack the nuclear translocation signal. These isoforms may be invol
ved in the regulation of CREB-mediated transcription. (C) 1996 Academi
c Press, Inc.