[Expression and activity of polymorphisms in the 67-kDa protein of the NADPH oxidase system].
The NADPH oxidase system plays a central role in the antimicrobial activity of phagocytes. This system is initiated by the translocation of cytosolic proteins p67phox, p47phox and p40phox to be in close contact with membrane flavocytochrome b558. This event begins the electron transfer from cytosolic NADPH to molecular oxygen to produce superoxide anions. Herein, a functional analysis is presented of p67phox polymorphisms identified from healthy humans. Mutations were generated in the p67phox cDNA by site-directed mutagenesis and then transiently expressed in COS7 cells that also expressed gp91phox, p22phox, and p47phox from stable transgenes. The changes Va1166lle, Pro329Ser and His389Gln correspond to possible polymorphisms identified in healthy individuals revealed a functional activity similar to COSphox cells transiently transfected with WT p67phox; therefore, these modifications are not associated with genetic deficiencies in NADPH oxidase. In conclusion, the COSphox system represents an easily transfectable model for analysis of NADPH oxidase function in intact cells. The analysis of mutant derivatives of p67phox provides insight into molecular mechanisms by which this subunit regulates the NADPH oxidase.
Arias
Andrés Augusto
AA
Grupo de Inmunodeficiencias Primarias, Corporación Biogénesis, Universidad de Antioquia, Medellín, Antioquia, Colombia. aarias@quimbaya.udea.edu.co
Dinauer
Mary C
MC
Ding
Jiabin
J
Matute
Juan David
JD
Patiño
Pablo Javier
PJ
D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D006801:Humans; D019255:NADPH Oxidases / Q000235:genetics*; D010586:Phagocytes / Q000502:physiology; D010750:Phosphoproteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D013481:Superoxides / Q000378:metabolism
D010750:Phosphoproteins; C079789:neutrophil cytosol factor 67K; D013481:Superoxides; D019255:NADPH Oxidases