Abstract
Purpose:
Gelatinous drop-like corneal dystrophy (GDLD) is a rare autosomal recessive disorder caused by biallelic loss-of-function mutations within the tumor-associated calcium signal transducer 2 (TACSTD2) gene, and is characterized by the reduction of tight junction-related proteins and a resultant loss of barrier function. Protein kinase C-alpha (PKC-alpha) is known to be involved in altering the function of tight-junctions. The purpose of this present study was to investigate the involvement of PKC-alpha in GDLD.
Methods:
Immortalized corneal epithelial cells (CECs), which we previously established to have similar characteristics as in vivo GDLD CECs, were seeded on a culture well and then cultured in growth medium. After the cells had reached 100% confluence, the medium was switched to a differentiation medium and the cells were cultured for an additional 7 days. The expression levels of PKC-alpha mRNA , PKC-alpha protein, and tight junction-related proteins claudin (CLDN)-1 and CLDN7 were then examined using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot analysis.
Results:
The expression levels of CLDN1 and CLDN7 proteins in GDLD CECs was significantly lower compared to the normal CECs. The mRNA level of PKC-alpha in the GDLD cells was upregulated compared to the normal cells. In addition, the PKC-alpha protein was found to be highly expressed in the GDLD cells.
Conclusions:
The findings of this study show that PKC-alpha may be involved in the tight- junction complex in GDLD.
Keywords: 480 cornea: basic science •
482 cornea: epithelium •
494 degenerations/dystrophies