INSTITUTO DE BIOQUIMICA Y MEDICINA MOLECULAR PROFESOR ALBERTO BOVERIS
Unidad Ejecutora - UE
capítulos de libros
Enzymatic Sources of Nitric Oxide during Seed Germination
M. SIMONTACCHI, S. JASID, S. PUNTARULO.
Nitric Oxide in Plant Growth, Development and Stress Physiology. Plant Cell Monographs
Lugar: Berlin, Heidelberg, Alemania; Año: 2007; p. 73 - 90
NO is an inorganic free radical gaseous molecule which has been shown to play an unprecedented range of roles in biological systems. Taking into account these numerous functions and the reports indicating that NO can regulate processes related to plant growth and development, one aspect that needs to be clarify is the endogenous sources of generation and the variations of NO levels upon plant cycle. In the present report the main endogenous sources of cellular NO production in plant tissues are considered, and the contribution of enzymatic sources are analyzed upon seed germination. Non-enzymatic generation of NO from NO2- under conditions of low pH could be of considerable importance since significant amounts of NO2- could be found in the plant tissues, however at least under the reported experimental conditions, enzymatic activity seems to be more relevant to total NO generation allowing a strict control of NO steady state concentration. The complexity of the overall scenario presented here shows the need for further studies into NO production and consumption pathways, mainly in germinating seeds exposed to fluctuating environmental conditions.