The sulfation of tyrosine residues is an important post-translational modification involved in the regulation of protein function. We examined the activity of worm tyrosylprotein sulfotransferase (TPST-1) on a typical cuticle collagen, ROL-6, in C. elegans. We verified that TPST-1 sulfates three tyrosine residues of ROL-6 in vitro. We found that these tyrosine residues are important for the secretion of ROL-6::GFP. Mutant ROL-6::GFP proteins that contain more than two substitutions of the target tyrosine residues are severely deficient in cuticle localization. Consistently, knock down of tpst-1 blocked the cuticle localization of ROL-6::GFP. Therefore, the sulfation of ROL-6 by TPST-1 is critical for the proper localization of ROL-6. We also confirmed that worm TPST-1 is localized to the trans-Golgi network (TGN). Our results indicate that TPST-1 regulates cuticle organization by promoting the transport of ROL-6 from the TGN to the cuticle.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation funded by the Korean Government (R0A-2007-000-20011-0), WCU (World Class University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R31-2008-000-10086 -0), and partly by KRF-2006 -005-J04502. Additionally, S.Y.P. and D.H.K. are fellowship awardees of the Brain Korea 21 program. This work was made possible through the use of research facilities in the Yonsei Center for Biotechnology. This work was also supported, in part, by research grants from the National Cancer Center (NCC-0510583 and NCC-0810070), South Korea. We thank the Caenorhabditis Genetics Center (CGC) for providing mutant worms, and Dr. Mello for distributing the pRF4 plasmid.
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cell Biology