RT Journal Article
SR Electronic
T1 Alzheimer's β-Secretase (BACE1) Regulates the cAMP/PKA/CREB Pathway Independently of β-Amyloid
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 11390
OP 11395
DO 10.1523/JNEUROSCI.0757-12.2012
VO 32
IS 33
A1 Yaomin Chen
A1 Xiumei Huang
A1 Yun-wu Zhang
A1 Edward Rockenstein
A1 Guojun Bu
A1 Todd E. Golde
A1 Eliezer Masliah
A1 Huaxi Xu
YR 2012
UL http://www.jneurosci.org/content/32/33/11390.abstract
AB β-Amyloid protein (Aβ), the major component of neuritic plaques in Alzheimer's disease (AD), is derived from proteolytic cleavages of the amyloid precursor protein (APP) by β-site APP-cleaving enzyme 1 (BACE1) and the γ-secretase complex. BACE1 is the rate-limiting enzyme for Aβ production, and an increase in BACE1 level/activity contributes to the pathogenesis of sporadic AD. In addition to cleaving APP for Aβ generation, BACE1 plays multiple physiological roles including the regulation of synaptic functions. Here, we found that overexpression of BACE1 reduces cAMP response element binding protein (CREB) phosphorylation, protein kinase A (PKA) activity, and cAMP levels, whereas downregulation of BACE1 has the opposite effect. We showed that BACE1's effect is independent of its activity for Aβ production, which is corroborated by the observation that BACE1 transgenic mice have impaired learning/memory in the absence of neurotoxic human Aβ. Furthermore, we demonstrated that BACE1 interacts via its transmembrane domain with adenylate cyclase, resulting in reduction of cellular cAMP levels and thus PKA inactivation and reduced CREB phosphorylation. Our study suggests that in addition to its function as the β-secretase to produce Aβ, BACE1 may contribute to the memory and cognitive deficits typical of AD by regulating the cAMP/PKA/CREB pathway, which is important for memory functions.