Abstract
Purpose. PAX6 heterozygosity (PAX6+/-) causes aniridia and aniridia-related keratopathy (ARK) in humans, but the pathway from gene dosage deficiency to clinical disease has not been fully characterized. Recently, the authors suggested a model of a chronic wound state exacerbated by oxidative stress, showed the barrier function of Pax6+/- corneas is compromised and suggested Pax6+/- corneas show the molecular signature of a perpetual wound-healing state.
Methods. Pax6+/- mice were used as a model for Pax6-related corneal diseases and in vivo wound-healing assays. Immunohistochemistry and electron microscopy analyses were performed on mutant and wounded corneas.
Results. This work reports defects in keratin, desmoplakin, and actin-based cytoskeletal structures in Pax6+/- cells. During wild-type corneal reepithelialization, cell fissures and desquamation, intracellular vesicles, intercellular gaps, and filopodialike structures were apparent, similar to the phenotypes seen in “unwounded” Pax6+/- corneal epithelia. Pax6+/- cells and wounded wild-type cells showed changed patterns of desmoplakin and actin localization. Protein oxidation and ERK1/2 and p38 MAPK phosphorylation were barely detected in the basal cells of intact wild-type corneal epithelia, but they were found in basal wild-type cells near the wound edge and throughout Pax6+/- corneal epithelia.
Conclusions. These data show that cell junctions and cytoskeleton organization are dynamically remodeled in vivo by wounding and in Pax6+/- corneas. This apparent wound-healing phenotype contributes to the clinical aspects of ARK.
Methods. Pax6+/- mice were used as a model for Pax6-related corneal diseases and in vivo wound-healing assays. Immunohistochemistry and electron microscopy analyses were performed on mutant and wounded corneas.
Results. This work reports defects in keratin, desmoplakin, and actin-based cytoskeletal structures in Pax6+/- cells. During wild-type corneal reepithelialization, cell fissures and desquamation, intracellular vesicles, intercellular gaps, and filopodialike structures were apparent, similar to the phenotypes seen in “unwounded” Pax6+/- corneal epithelia. Pax6+/- cells and wounded wild-type cells showed changed patterns of desmoplakin and actin localization. Protein oxidation and ERK1/2 and p38 MAPK phosphorylation were barely detected in the basal cells of intact wild-type corneal epithelia, but they were found in basal wild-type cells near the wound edge and throughout Pax6+/- corneal epithelia.
Conclusions. These data show that cell junctions and cytoskeleton organization are dynamically remodeled in vivo by wounding and in Pax6+/- corneas. This apparent wound-healing phenotype contributes to the clinical aspects of ARK.
| Original language | English |
|---|---|
| Pages (from-to) | 1415-1423 |
| Number of pages | 9 |
| Journal | Investigative Ophthalmology & Visual Science |
| Volume | 51 |
| Issue number | 3 |
| Early online date | 20 Nov 2009 |
| DOIs | |
| Publication status | Published - Mar 2010 |