Møller Morten, Sparre Thomas, Bache Nicolai, Roepstorff Peter, Vorum Henrik
Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark.
Proteomics. 2007 Jun;7(12):2009-18. doi: 10.1002/pmic.200600963.
The pineal gland secretes the hormone melatonin. This secretion exhibits a circadian rhythm with a zenith during night and a nadir during day. We have performed proteome analysis of the superficial pineal gland in rats during daytime and nighttime. The proteins were extracted and subjected to 2-DE. Of 1747 protein spots revealed by electrophoresis, densitometric analysis showed the up-regulation of 25 proteins during nighttime and of 35 proteins during daytime. Thirty-seven of the proteins were identified by MALDI-TOF MS. The proteins up-regulated during the night are involved in the Krebs cycle, energy transduction, calcium binding, and intracellular transport. During the daytime, enzymes involved in glycolysis, electron transport, and also the Krebs cycle were up-regulated as well as proteins taking part in RNA binding and RNA processing. Our data show a prominent day-night variation of the protein levels in the rat pineal gland. Some proteins are up-regulated during the night concomitant with the melatonin secretion of the gland. Other proteins are up-regulated during the day indicating a pineal metabolism not related to the melatonin synthesis.
松果体分泌褪黑素。这种分泌呈现出昼夜节律，在夜间达到峰值，在白天降至最低点。我们对大鼠白天和夜间的松果体浅层进行了蛋白质组分析。提取蛋白质并进行二维电泳。电泳显示的1747个蛋白点中，密度分析表明夜间有25种蛋白上调，白天有35种蛋白上调。通过基质辅助激光解吸电离飞行时间质谱鉴定出了37种蛋白。夜间上调的蛋白参与三羧酸循环、能量转导、钙结合和细胞内运输。在白天，参与糖酵解、电子传递以及三羧酸循环的酶上调，同时参与RNA结合和RNA加工的蛋白也上调。我们的数据显示大鼠松果体中蛋白质水平存在显著的昼夜变化。一些蛋白在夜间随着腺体褪黑素的分泌而上调。其他蛋白在白天上调，表明松果体的代谢与褪黑素合成无关。
