First Author | Yan L | Year | 2006 |
Journal | J Neurosci | Volume | 26 |
Issue | 37 | Pages | 9434-8 |
PubMed ID | 16971527 | Mgi Jnum | J:112465 |
Mgi Id | MGI:3656363 | Doi | 10.1523/JNEUROSCI.2538-06.2006 |
Citation | Yan L, et al. (2006) DARPP-32 involvement in the photic pathway of the circadian system. J Neurosci 26(37):9434-8 |
abstractText | The multifunctional regulator of protein kinases and phosphatases dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32) is an important molecular target of the dopamine signaling pathway. In the present study, we investigated the possible involvement of DARPP-32 regulation in the circadian system using DARPP-32 knock-out (KO) mice. These mice showed normal entrainment to a 12 h light/dark cycle and free run in constant darkness with a period similar to that of wild-type controls. After light exposure, however, the behavioral phase-delay response and the expression of light-induced clock gene mPer2 were attenuated in the DARPP-32 KO mice. Attenuated phase delays were also seen in animals bearing a point mutation in DARPP-32 at the PKA (Thr34) but not at the casein kinase I (Ser130) phosphorylation site. We next examined DARPP-32 expression in the retina and intergeniculate leaflet (IGL), both of which convey light information to the suprachiasmatic nucleus (SCN), the locus of a master circadian clock, and in the SCN itself. DARPP-32 was expressed in the retina but not in the IGL or the SCN. The results indicate that DARPP-32 is involved in the retinal pathway transmitting photic information that resets the circadian clock. |