FIGURE 10.

Proposed model for heterocomplex formation with PDX1.3 and PDX1.2, in particular. PDX1.3 can exist in an hexamer/dodecamer equilibrium as depicted by the blue rings. PDX1.3 is subject to ubiquitination (Ub) and degradation through the proteasome pathway. During localized oxidative stress (e.g. singlet oxygen), PDX1.2 is induced (depicted as an amber ring) and can form a heterocomplex with PDX1.3. The pale blue star denotes the N-terminal modification of the PDX1.2 protein that is required for enhancement of PLP biosynthesis by PDX1.3.