Cleavage proteolytic

FIGURE 16.28 HIV mRNA provides the genetic information for synthesis of a polyprotein. Proteolytic cleavage of this polyprotein by HIV protease produces the individnal proteins required for viral growth and cellular infection. 

Amyloid precursor protein (APP) is the precursor of (3-amyloid, the main component of senile plaques found in the brain of Alzheimer patients. The production of (3-amyloid from APP to the cells from abnormal proteolytic cleavage of the amyloid precursor protein. Enzymes involved in this cleavage may be suitable targets for the therapy of Alzheimer s disease. 

Proteinase-activated Receptors. Figure 1 Activation of proteinase-activated receptors (PARs) through proteolytic cleavage with serine proteinases (1) and independent of cleavage though PAR-specific activating peptides (2). 

Transmembrane Signaling. Figure 2 Membrane topology of receptors that are associated with effector proteins. Upon binding to their cognate ligands (cyan), receptor proteins without intramolecularly linked effector domain couple via transducer proteins (yellow) to or directly recruit and activate effector proteins (red). Notch receptors release their transducer domains upon proteolytic cleavage, a, p and y stand for G-protein a-, p- and y-subunits, respectively. 

Mitochondrial Factors Involved in Proteolytic Cleavage and Assembly of Proteins 140... 

The maturation of the precursor protein involves their proteolytic cleavage. There are two proteins important in this cleavage, so-called processing protease and protease enhancing peptide. These are now believed to be nonidentical subunits of the same enzyme. The structural requirements for recognition of the cleavage site are not fully understood and except for a positively charged residue at position (-2) there is no consensus sequence around this site. 

Proteolytic cleavage may also activate the chemokine. For example, CCL14 naturally displays a very weak affinity for CCRl and is unable to bind to CCR3 and CCR5 but shows an increase in CCRl affinity and gain of CCR3 and CCR5 affinity associated with chemotactic activity on lymphoblasts, monocytes, and eosinophils upon... 

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