The nitration of proteins in platelets

Nitric oxide has many important physiological functions, but it may also fo rm an important oxidant, peroxynitrite, as a consequence of its reaction wi th superoxide anions. Peroxynitrite is capable of nitrating the aromatic am ino acids in proteins, particularly tyrosine. Nitrated proteins are found i n tissues of a variety of diseases where inflammation occurs. However, our recent work suggests that more selective nitration of specific proteins may occur during normal physiological processes, such as platelet activation b y collagen. It is not yet clear what role this may play in the normal cell biology, but there is potential to be a role in signal transduction mechani sms, possibly by influencing tyrosine phosphorylation or dephosphorylation. (C) 2001 Academie des Sciences/Editions scientifiques et medicales Elsevie r SAS.