Conserved autophagy and diverse cell wall composition: Unifying features of vascular tissues in evolutionarily distinct plants.

Our study's findings indicate that the involvement of autophagy in plants is universal during the development of tracheary elements that are dead at maturity and sieve elements that remain alive. Given the conserved nature of autophagy, and its function in protoplast degradation for uninterrupted flow, autophagy may have played a vital role in the development of increasingly complex biological organizations, including the formation of vascular tissues. On the other hand, different cell wall compositions of xylem and phloem in different species may indicate diverse functionality and potential of substance transport, which is critical in plant evolution.