Title:Localization Patterns of Sumoylation Enzymes E1, E2 and E3 in Ocular Cell Lines Predict Their Functional Importance
VOLUME: 18 ISSUE: 8
Author(s):Xiaodong Gong, Qian Nie, Yuan Xiao, Jia-Wen Xiang, Ling Wang, Fangyuan Liu, Jia-Ling Fu, Yunfei Liu, Lan Yang, Yuwen Gan, Huimin Chen, Zhongwen Luo, Ruili Qi, Zhigang Chen, Xiangcheng Tang and David Wan-Cheng Li*
Affiliation:The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230
Keywords:SAE1, UBA2, UBC9, PIAS1, RanBP2, αTN4-1, HLE, FHL124, N/N1003A, ARPE-19.
Abstract:Purpose: It is well established now that protein sumoylation acts as an important
regulatory mechanism mediating control of ocular development through regulation of multiple
transcription factors. Yet the functional mechanisms of each factor modulated remain to be further
explored using the available in vitro systems. In this regard, various ocular cell lines including HLE,
FHL124, αTN4-1, N/N1003A and ARPE-19 have been demonstrated to be useful for biochemical
and molecular analyses of normal physiology and pathogenesis. We have recently examined that
these cell lines express a full set of sumoylation enzymes E1, E2 and E3. Following this study,
here we have examined the localization of these enzymes and determined their differential
localization patterns in these major ocular cell lines.
Methods: The 5 major ocular cell lines were cultured in Dulbecco’s modified Eagle’s medium
(DMEM) containing fetal bovine serum (FBS) or rabbit serum (RBS) and 1% Penicillin-
Streptomycin. The localization of the 3 major sumoylation enzymes in the 5 major ocular cell lines
were determined with immunohistochemistry. The images were captured with a Zeiss LSM 880
confocal microscope.
Results: we have obtained the following results: 1) The sumoylation enzymes SAE1, UBC9 and
PIAS1 are distributed in both nucleus and cytoplasm, with a much higher level concentrated in the
nucleus and the neighboring cellular organelle zone in all cell lines; 2) The sumoylation enzyme
UBA2 was highly concentrated in both cytoplasm membrane, cytoskeleton and nucleus of all cell
lines; 3) The ligase E3, RanBP2 was exclusively localized in the nucleus with homogeneous
distribution.
Conclusions: Our results for the first time established the differential localization patterns of the
three types of sumoylation enzymes in 5 major ocular cell lines. Our establishment of the
differential localization patterns of the three types of sumoylation enzymes in these cell lines help to
predict their functional importance of sumoylation in the vision system. Together, our results
demonstrate that these cell lines can be used for assay systems to explore the functional
mechanisms of sumoylation mediating ocular development and pathogenesis.
