Jasmonate Biosynthesis Across Bryophyte Lineages: Lessons from Marchantia polymorpha and Beyond

Area of Science:

• Plant Biology
• Phytohormone Research
• Evolutionary Botany

Background:

• Jasmonates (JAs) are crucial plant hormones regulating development and defense.
• Angiosperm JA biosynthesis is well-understood, but bryophyte pathways remain largely unexplored.
• Understanding JA signaling is vital for improving crop yields and food safety.

Purpose of the Study:

• To elucidate the step-by-step jasmonate biosynthetic pathway in bryophytes.
• To compare bryophyte JA biosynthesis with that of angiosperms, identifying similarities and differences.
• To provide a foundation for future research into the evolution of plant hormone signaling.

Main Methods:

• Tracing the pathway from polyunsaturated fatty acid (PUFA) precursors.
• Analyzing lipoxygenase oxygenation and downstream enzymatic reactions.
• Investigating processing and catabolic modifications of bioactive jasmonates.

Main Results:

• Bryophytes possess an expanded fatty acid repertoire, including eicosanoids like arachidonic acid and eicosapentaenoic acid.
• A key step involves cis-to-iso isomerization in forming bioactive jasmonates (dn-iso-OPDA and Δ4-dn-iso-OPDA).
• Mechanistic parallels and divergences with angiosperm pathways were identified.

Conclusions:

• Deciphering bryophyte jasmonate biosynthesis is essential for understanding the evolutionary origins of JA signaling.
• This research highlights the unique biochemical strategies employed by early land plants.
• Future studies will focus on resolving remaining questions and exploring evolutionary implications.