Abstract

Does N-Nitrosomelatonin Compete with S-Nitrosothiols as a Long Distance Nitric Oxide Carrier in Plants?

Neha Singh, Harmeet Kaur, Sunita Yadav and Satich C Bhatla

Plants transmit a variety of signaling molecules from roots to aerial parts, and vice-versa, in response to their growth conditions (environment, nutrients, stress factors etc.). A signaling molecule should be produced quickly, induce a defined effect within the cell and be removed or metabolized rapidly when not required. Nitric oxide (NO) plays significant signaling roles in plant cells since it has all the above-stated features. It is a gaseous free radical, can gain or lose an electron, has short half-life (Ì´ 30 sec) and it can exist in three interchangeable forms, namely the radical (NO•), the nitrosonium cation (NO+) and as nitroxyl radical (NO). NO is soluble in aqueous as well as lipid phases. It rapidly reacts with oxygen to form NO2 and can react with other potential signaling molecules as well (eg. superoxide anions (O2•¯). In the recent past, NO has been observed to regulate various growth and developmental processes.