CYBB

Cytochrome b-245 heavy chain also known as cytochrome b(558) subunit beta or NADPH oxidase 2 or Nox2 is a protein that in humans is encoded by the CYBB gene. The protein is a super-oxide generating enzyme which forms reactive oxygen species (ROS).

Function

Nox2, or Cytochrome b (-245) is composed of cytochrome b alpha (CYBA) and beta (CYBB) chain. It has been proposed as a primary component of the microbicidal oxidase system of phagocytes.

Also, many of the functions for Nox2 are linked through the many functions of NADPH oxidase since Nox2 is one of the several isoforms of the gp91^phox catalytic subunit of NADPH oxidase.

There has been recent evidence that shows that it plays an important role in atherosclerotic lesion development in the aortic arch, thoracic, and abdominal aorta.

It has also been shown to play a part in determining the size of a myocardial infarction due to its connection to ROS which play a role in myocardial reperfusion injury. This was a result of the relation between Nox2 and the signalling towards neutrophil invasion. Also, it increases golbal post-reperfusion oxidative stress probably due to decreased STAT3 and Erk phosphorylation.