Sepúlveda M Rosario, Marcos Daniel, Berrocal Maria, Raeymaekers Luc, Mata Ana M, Wuytack Frank
Laboratory of Ca2+-Transport ATPases, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Campus Gasthuisberg O&N1, BE-3000 Leuven, Belgium.
Mol Cell Neurosci. 2008 Aug;38(4):461-73. doi: 10.1016/j.mcn.2008.02.012. Epub 2008 Mar 18.
Ca2+ and Mn2+ play an important role in many events in the nervous system, ranging from neural morphogenesis to neurodegeneration. As part of the homeostatic control of these ions, the Secretory Pathway Ca2+-ATPase isoform 1 (SPCA1) mediates the accumulation of Ca2+ or Mn2+ with high affinity into Golgi reservoirs. This SPCA1 represents a relatively recently characterized P-type pump that is highly expressed in nervous tissue, but information on its involvement in neural maturation is currently lacking. In this study, we have analyzed the expression and distribution of the SPCA1 pump in mouse brain during postnatal development. RT-PCR and Western blot assays showed that SPCA1 is particularly highly expressed at nearly constant levels during this entire period of development in cortex, hippocampus, and cerebellum. In spite of the apparently unchanged expression levels, functional assays showed that SPCA-associated Ca2+-ATPase activity increased with the stage of development in these areas. Immunohistochemical studies pointed to SPCA1 localization in Golgi stacks of the soma and the initial part of primary dendritic trunk in main cortical, hippocampal and cerebellar neurons from the earliest postnatal stages. This suggests a potential role in intracellular signaling and in Golgi secretory processes involved in dendritic growth and in functional maturation of the mouse nervous system.
钙离子（Ca2+）和锰离子（Mn2+）在神经系统的许多活动中发挥着重要作用，范围从神经形态发生到神经退行性变。作为这些离子稳态控制的一部分，分泌途径Ca2+ - ATP酶同工型1（SPCA1）介导Ca2+或Mn2+以高亲和力积累到高尔基体贮库中。这种SPCA1代表一种相对较新被鉴定的P型泵，在神经组织中高度表达，但目前缺乏其参与神经成熟的相关信息。在本研究中，我们分析了出生后发育过程中小鼠脑内SPCA1泵的表达和分布。逆转录聚合酶链反应（RT-PCR）和蛋白质免疫印迹分析表明，在整个发育期间，SPCA1在皮质、海马和小脑中均以几乎恒定的水平特别高表达。尽管表达水平明显未变，但功能分析表明，这些区域中与SPCA相关的Ca2+ - ATP酶活性随发育阶段而增加。免疫组织化学研究表明，从出生后最早阶段起，SPCA1定位于主要皮质、海马和小脑神经元胞体的高尔基体堆叠以及初级树突干的起始部分。这表明其在细胞内信号传导以及参与小鼠神经系统树突生长和功能成熟的高尔基体分泌过程中可能发挥作用。
