Protein involved in the jasmonic acid (jasmonate, JA) signaling pathway (e.g. transport and signal transduction) that regulates many aspects of plant growth, development and cellular signaling (e.g. growth inhibition, senescence, tuber formation, response to wounding, plant defense, and leaf abscission). This phytohormone and its derivatives such as methyl jasmonate (MeJA) can be synthesized from the fatty acid linolenic acid in the oxylipin octadecanoid pathway.