Methyl jasmonate signaling and signal crosstalk between methyl jasmonate and abscisic acid in guard cells.

Plants tightly control stomatal aperture in response to various environmental changes. A drought-inducible phytohormone, abscisic acid (ABA), triggers stomatal closure and ABA signaling pathway in guard cells has been well studied. Similar to ABA, methyl jasmonate (MeJA) induces stomatal closure in various plant species but MeJA signaling pathway is still far from clear. Recently we found that Arabidopsis calcium dependent protein kinase CPK6 functions as a positive regulator in guard cell MeJA signaling and provided new insights into cytosolic Ca2+-dependent MeJA signaling. Here we discuss the MeJA signaling and also signal crosstalk between MeJA and ABA pathways in guard cells.