A hypothesis about cellular signaling with nitric oxide in the earliest life forms in evolution.
We propose that nitric oxide participated as an extracellular and intracellular messenger in the early evolution of life. From a toxic and noxious substance it evolved into an important material for cellular communication and regulation with unique chemistry and properties. The presence of some nitric oxide complexes in extraterrestrial samples may support evidence for life forms in the past or present. Although nitric oxide probably participated in the evolution and maintenance of life, if pollution continues at an ever-increasing rate, it could also end life on the planet as we know it today.
Department of Integrative Biology and Pharmacology, Institute of Molecular Medicine and University of Texas Health Science Center, Houston, TX 77030, USA. Ferid.Murad@uth.tmc.edu
Ferid
F
Murad
Roger
R
Barber
D000818:Animals; D005075:Biological Evolution; D005118:Extraterrestrial Environment / Q000737:chemistry; D006801:Humans; D009569:Nitric Oxide / Q000737:chemistry* / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*
D009569:Nitric Oxide