Pizzio Gastón A, Golombek Diego A
Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Roque Sáenz Peña 352 - Bernal, B1876BXD, Buenos Aires, Argentina.
J Mol Neurosci. 2008 Feb;34(2):187-92. doi: 10.1007/s12031-007-9021-y. Epub 2007 Dec 5.
MAP kinases (MAPKs) play a key role in photic entrainment signaling in the suprachiasmatic nuclei (SCN), the mammalian circadian clock. The control of MAPKs is a fine balance between specific kinases (MEKs) and phosphatases (MKPs), whose orchestration in the SCN is still unresolved. We have found MKP1/2 and MKP3 immunoreactive-cells in the hamster SCN, whose levels are rapidly increased in response to transient light stimulation in the subjective night (CT 18), when light is able to entrain the clock. Moreover, the expression level of MKP3 varies under light-dark cycles and constant darkness, peaking at noon, when MAPKs are in their activated state and begin their inactivation. These results show a different perspective on MAPKs in the SCN, which includes its regulation by a complex net of phosphatases.
丝裂原活化蛋白激酶（MAPKs）在视交叉上核（SCN）（哺乳动物的生物钟）的光诱导信号传导中起关键作用。MAPKs的调控是特定激酶（MEKs）和磷酸酶（MKPs）之间的精细平衡，其在SCN中的协调作用仍未明确。我们在仓鼠SCN中发现了MKP1/2和MKP3免疫反应性细胞，在主观夜间（CT 18）受到短暂光刺激时，其水平会迅速升高，此时光能够调节生物钟。此外，MKP3的表达水平在明暗周期和持续黑暗条件下会发生变化，在中午达到峰值，此时MAPKs处于激活状态并开始失活。这些结果展示了SCN中MAPKs的不同视角，其中包括其受复杂磷酸酶网络调控的情况。
