Product identification and adenylyl cyclase activity in chloroplasts of Nicotiana tabacum

Abstract

In view of the ongoing debate on plant cyclic nucleotide metabolism, especially the functional presence of adenylyl cyclase, a novel detection method has been worked out to quantify the reaction product. Using uniformly labelled (15)N-ATP as a substrate for adenylyl cyclase, a qualitative and quantitative liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) method was developed to measure de novo formed (15)N-adenosine 3',5'-cyclic monophosphate. Adenylyl cyclase activity was observed in chloroplasts obtained from Nicotiana tabacum cv. Petit Havana and the kinetic parameters and influence of various metabolic effectors are discussed in their context.

Ca2+, cAMP, and transduction of non-self perception during plant immune responses

“…Nonetheless, cAMP has been unequivocally documented to be present in plant cells (27,40). Adenylyl cyclase activity as well as cAMP phosphodiesterase activity is present in plants (4,27).…”

“…Nonetheless, cAMP has been unequivocally documented to be present in plant cells (27,40). Adenylyl cyclase activity as well as cAMP phosphodiesterase activity is present in plants (4,27). Intriguingly, application of fungal extracts to plant cell cultures affects the level of extractable activities of cyclase (i.e., rising in the first few minutes) and phosphodiesterase (declining during this time) in a manner consistent with generation of transient cAMP elevations in a plant cell upon perception of a pathogen (4).…”

“…In consideration of this point, we took a pharmacological approach to manipulate endogenous cAMP. Dedioxyadenosine (DDA) and 1,3-diazinane-2,4,5,6-tetrone (alloxan) are well characterized inhibitors of animal adenylyl cyclase (23)(24)(25), and block cAMP-dependent signaling in plants (26)(27)(28)(29). Results presented in Fig.…”

Novel type of adenylyl cyclase participates in tabtoxinine-β-lactam-induced cell death and occurrence of wildfire disease inNicotiana benthamiana

“…AC activity was reported in alfalfa and tobacco. 18,19 Plant AC has been isolated and enzymatic properties were also analyzed in Zea mays and A. thaliana, indicating AC is in plants. 13,14 In this study, we isolated AC (NbAC) from N. benthamiana (Fig.…”

Cyclic Adenosine Monophosphate Regulates Calcium Channels in the Plasma Membrane of Arabidopsis Leaf Guard and Mesophyll Cells

“…Furthermore, a partial clone encoding a protein with homology to fungal adenylate cyclase has been identified in corn pollen; importantly, its translation product was shown to have adenylate cyclase activity (9). Recent work has identified adenylate cyclase activity in (tobacco) chloroplasts (11), suggesting its ubiquitous presence in photosynthetic tissue. cAMP has been associated with cation uptake and associated cell growth/expansion in pollen tubes (9,12), as well as cell cycle progression and hormone signaling in plants (see Refs.…”