In healthy individuals, the activity of the protein kinase P1 or PKR remains constant. Both of these enzymes, therefore, could be used as markers to evaluate the state of the disease and recovery. Measurements of these enzymes and detection of their mRNA level are very important in studying mechanism of interference with signal transduction in lymphocytes of patients with chronic fatigue and other immune dysfunction syndromes. Recently, a new type of endonuclease inhibitor was cloned and characterized. It was found that this inhibitor either is absent or very low in these patients.
L is induced.
This enzyme has the capacity to degrade single stranded RNA of hypotethical virus involved in the pathway of interferon action. Measurements of RNAase-L inhibitor along with PKR may confirm virus as a cause of chronic fatigue syndrome. Levels of protein Kinase-C were found to be abnormal in patients with low NK activity. Measurements of PKC are very important in studying the mechanism of interference with signal transduction in lymphocytes of patients with chronic fatigue and other immune dysfunction syndromes. This signal transduction system which consists of eleven different isozymes, gets activated upon ligand-stimulation of transmembrane receptors by hormones, neurotransmitters, and growth factors.