Differential Expression of Seven De-sumoylation Enzymes (SENPs) in Major Ocular Tissues of Mouse Eye.

Protein Sumoylation is one of the most important and prevalent posttranscriptional modification. Increasing evidence have shown that the SENPs (sentrin/SUMO-specific proteases) are critical for steady-state levels of SUMO modification of target proteins, and protein de-sumoylation modulates a great diversity of biological processes including transcription, development, differentiation, neuroprotection, as well as pathogenesis. In the vertebrate eye, we and others have previously shown that sumoylation participated in the differentiation of major ocular tissues including retina and lens. However, the biological significance of seven SENP enzymes: SENP1 to 3 and SENP5 to 8 have not be fully investigated in the ocular tissues. In the present study, using qRT-PCR and western blot analysis, we have compared the differential expression patterns of seven SENP enzymes in four major ocular tissues of mouse eye. Our results demonstrated that at the mRNA level, all SENPs were highly expressed in retina, and much reduced expression patterns in cornea, lens epithelium and lens fiber. At the protein level, SENP1 to -3, and SENP6 were highly abundant in cornea, while SENP5, SENP7 and SENP8 were enriched in retina, and these SENPs were relatively less abundant in lens tissues. Our results established a basis for further investigation of protein de-sumoylation functions in vertebrate eye.