Calcium as Second Messengers

Pages 4 (1004 words)
Download 0
Second messengers are molecules that relay signals received at receptors on the cell surface - such as the arrival of protein hormones, growth factors, etc. - to target molecules in the cytosol and/or nucleus. But in addition to their job as relay molecules, second messengers serve to greatly amplify the strength of the signal.


Calcium ions are also important intracellular messengers. In fact, calcium ions are probably the most widely used intracellular messengers (Kimball, 2006). Calcium plays a fundamental role in a variety of cellular functions. It is involved in contraction, secretion, endocytosis, transport across membranes and in more general processes such as cell motility, cell growth and cell division (De Robertis & De Robertis, 1987). Calcium is one of the most important second messenger molecules, with a diverse array of effectors. The intracellular Ca2+ plays a role as the second messenger in the hypotonic stress-induced Na+ transport by stimulating the transcription of SGK1 and ENaC subunits (Taruno, Niisato, Marunaka, 2007). Calcium directly moderates electrical activity, on a relatively fast time scale, through its control of calcium-dependent potassium channels. Long term effects are mediated by various kinases and phosphatases. Calcium is one of the activators of protein kinase C, which plays a role in synaptic plasticity. In a complex with calmodulin56, calcium is an activator or regulator of several enzymes, including calcium-calmodulin dependent protein kinase, which plays a role in synaptic plasticity, and adenylate cyclase, which produces cAMP, another important second messenger. ...
Download paper
Not exactly what you need?