Fig. 10.

Organization of cis-elements in the 5′-flanking region of the AGPL1 gene. The numbers refer to positions relative to the transcriptional start site, which is indicated by a triangle. +, up-regulated elements; in leaves, trans-factors binding to the PN1 and/or PN2 elements repressed transcriptional activity of the promoter. Deletion of PN-binding sites relieves this repression of PP-binding factors. When the PN binding activity to the trans-factors is reduced or less able to bind, this renders trans-factors unable to repress gene activity. Instead, the remaining complex, which may involve different PP binding activity, activates transcription.