Abstract
BackgroundMitogen activated protein kinase (MAPK) cascade is an important signaling cascade that operates in stress signal transduction in plants. The biologically active monoterpenoid indole alkaloids (MIA) produced in Catharanthus roseus are known to be induced under several abiotic stress conditions such as wounding, UV-B etc. However involvement of any signaling component in the accumulation of MIAs remains poorly investigated so far. Here we report isolation of a novel abiotic stress inducible Catharanthus roseus MAPK, CrMPK3 that may have role in accumulation of MIAs in response to abiotic stress.ResultsCrMPK3 expressed in bacterial system is an active kinase as it showed auto-phosphorylation and phosphorylation of Myelin Basic Protein. CrMPK3 though localized in cytoplasm, moves to nucleus upon wounding. Wounding, UV treatment and MeJA application on C. roseus leaves resulted in the transcript accumulation of CrMPK3 as well as activation of MAPK in C. roseus leaves. Immuno-precipitation followed by immunoblot analysis revealed that wounding, UV treatment and methyl jasmonate (MeJA) activate CrMPK3. Transient over-expression of CrMPK3 in C. roseus leaf tissue showed enhanced expression of key MIA biosynthesis pathway genes and also accumulation of specific MIAs.ConclusionResults from our study suggest a possible involvement of CrMPK3 in abiotic stress signal transduction towards regulation of transcripts of key MIA biosynthetic pathway genes, regulators and accumulation of major MIAs.
Highlights
Mitogen activated protein kinase (MAPK) cascade is an important signaling cascade that operates in stress signal transduction in plants
At least three myelin basic protein (MBP) phosphorylating kinases were observed after UV exposure whereas methyl jasmonate led to activation of single MAPK (Additional file 1: Figure 1)
CrMPK3 shows UV, wounding and methyl jasmonate (MeJA) inducible expression pattern that is in harmony with the expression pattern of many of the key genes and regulators of monoterpenoid indole alkaloids (MIA) biosynthetic pathway and MIA accumulations (Figure 5) [33,37]
Summary
Mitogen activated protein kinase (MAPK) cascade is an important signaling cascade that operates in stress signal transduction in plants. The biologically active monoterpenoid indole alkaloids (MIA) produced in Catharanthus roseus are known to be induced under several abiotic stress conditions such as wounding, UV-B etc. Plants in order to cope-up with changing environmental conditions synthesize a wide variety of secondary metabolites, which acts as defence molecules and contribute to its overall growth and development. Biosynthesis of these compounds is often induced by various environmental stimuli and stress factors such as UV light or pathogen attack. The role of MAPKs has been implicated in various biological phenomena in plants including pathogen defense, abiotic stresses, cytokinesis and cell differentiation, and plant hormone signaling [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
