盘基网柄菌中趋化因子刺激的钙内流不依赖于环鸟苷酸。

Chemoattractant-stimulated calcium influx in Dictyostelium discoideum does not depend on cGMP.

作者信息

Veltman Douwe M, De Boer Jan Sietse, Van Haastert Peter J M

机构信息

GBB Research School, Department of Biochemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.

出版信息

Biochim Biophys Acta. 2003 Oct 13;1623(2-3):129-34. doi: 10.1016/j.bbagen.2003.08.006.

DOI:10.1016/j.bbagen.2003.08.006

PMID:14572910

Abstract

Chemoattractant stimulation of Dictyostelium cells leads to the opening of calcium channels in the plasma membrane, causing extracellular calcium to flux into the cell. The genetically uncharacterised mutants stmF and KI8 show strongly altered chemoattractant-stimulated cGMP responses. The aberrant calcium influx in these strains has provided evidence that the chemoattractant-stimulated calcium influx is potentiated by cGMP. We have tested this hypothesis in genetically defined mutants by measuring the calcium influx in a strain that lacks intracellular cGMP due to the disruption of two guanylyl cyclases, and in a strain with increased cGMP levels caused by the disruption of two cGMP-degrading phosphodiesterases. The results reveal that the calcium influx stimulated by cAMP or folic acid is essentially identical in these strains. We conclude that cGMP is not involved in chemoattractant-stimulated calcium influx.

摘要

对盘基网柄菌细胞的趋化因子刺激会导致质膜中的钙通道开放，使细胞外钙流入细胞。基因未鉴定的突变体stmF和KI8显示出趋化因子刺激的cGMP反应有强烈改变。这些菌株中异常的钙流入提供了证据，表明趋化因子刺激的钙流入由cGMP增强。我们通过测量由于两个鸟苷酸环化酶被破坏而缺乏细胞内cGMP的菌株以及由于两个cGMP降解磷酸二酯酶被破坏而cGMP水平升高的菌株中的钙流入，在基因定义的突变体中测试了这一假设。结果表明，在这些菌株中，由cAMP或叶酸刺激的钙流入基本相同。我们得出结论，cGMP不参与趋化因子刺激的钙流入。