The α2D/A‐adrenergic receptor‐linked membrane guanylate cyclase: a new signal transduction system in the pineal gland

FEBS Letters

Venkataraman, Venkateswar¹  Sharma, Rameshwar K.¹  Duda, Teresa¹ 

[1]The Unit of Regulatory and Molecular Biology, Departments of Cell Biology and Ophthalmology, NJMS, University of Medicine and Dentistry of New Jersey, Stratford, NJ 08084, USA

关键词: α2D/A-Adrenergic receptor;    ROS-GC1;    CD-GCAP;    Guanylate cyclase;   

DOI  :  10.1016/S0014-5793(98)00396-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In the pineal gland, the membrane guanylate cyclase activity was specifically stimulated by α_2D/A-adrenergic receptor (α_2D/A-AR) agonists. The agonists, however, did not stimulate the cyclase activity in the cell-free membranes. It was possible to stimulate the cyclase in cell-free membranes by the addition of the pineal soluble fraction, but this stimulation was Ca²⁺-dependent and α_2D/A-agonist-independent. It was also possible to achieve Ca²⁺-dependent stimulation of the cyclase by the direct addition of CD-GCAP to the isolated pineal membranes. CD-GCAP is a Ca²⁺-binding protein and is a specific activator of one of the two members of the ROS-GC subfamily of membrane guanylate cyclases, ROS-GC1. The soluble fraction of the pineal gland stimulated recombinant ROS-GC1 in a Ca²⁺-dependent fashion. The direct presence of both ROS-GC1 and CD-GCAP in the pineal was established by molecular cloning/PCR studies. The findings demonstrate the existence of a novel signal transduction mechanism – the linkage of the α_2D/A-AR signaling system with ROS-GC1 transduction system, occurring through intracellular Ca²⁺ via CD-GCAP.

【 授权许可】

Unknown