ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Roles of pectins in cell walls.

Cutsem, P. van and Messiaen, J.

Acta Horticulturae Year: 1993 Issue: No. 326 Pages: 93-104 Ref: 61 ref.

1993

บทคัดย่อ

Pectins in plant cell walls contain largely methylesterified homopolygalacturonic acid sequences. After deesterification by plant or pathogen pectin methylesterases, these sequences can cross-link through Ca bridges to form "egg boxes", but they are also subject to degradation by polygalacturonases (schematic diagrams are presented). The released fragments are elicitors of defence reactions and act on morphogenesis. The size dependency of most responses is probably due to the fact that the activity of the fragments depends on their ability to adopt the "egg box" conformation. In a limited number of cases, steps of the signal transduction chain have been studied (cytosolic Ca increase, protein phosphorylation, DNA transcription). The involvement of pectic fragments in fruit ripening is discussed from the point of view of wall softening.