Protein tyrosine-O-sulfation in the retina

Yogita Kanan, Adam Hoffhines, Alysha Rauhauser, Anne Murray, Muayyad R. Al-Ubaidi

Research output: Contribution to journalArticle


Tyrosine-O-sulfation, a post-translational modification, is catalyzed by two independent tyrosylprotein sulfotransferases (TPSTs). As an initial step towards understanding the role of TPSTs in retinal function, this study was undertaken to determine the extent to which tyrosine-O-sulfation of proteins is utilized in the retina. A previously characterized anti-sulfotyrosine antibody was used to determine the presence and localization of tyrosine-O-sulfated proteins (TOSPs) in the retina. Using Western blot, RT-PCR and immunohistochemical analyses, we detected TOSPs in the retinas from diverse species, including frog, fish, mouse and human. Some of the variability in the observed sizes of retinal TOSPs in the mouse, at least, may result from differential patterns of glycosylation; however, there seem to be species-specific sulfated retinal proteins as well. TOSPs were detected in most of the retinal layers as well as in the retinal pigment epithelium from human and mouse. Several retinal TOSPs were detected in the inter-photoreceptor matrix, which is consistent with the secreted nature of some sulfated proteins. Transcripts for both TPST-1 and TPST-2 were expressed in both the human and mouse retinas. These data show that retinal protein tyrosine-O-sulfation is highly conserved which suggest a functional significance of these proteins to retinal function and structure.

Original languageEnglish (US)
Pages (from-to)559-567
Number of pages9
JournalExperimental Eye Research
Issue number4
Publication statusPublished - Oct 2009
Externally publishedYes



  • post-translation modification
  • protein sulfation
  • RPE

ASJC Scopus subject areas

  • Ophthalmology
  • Cellular and Molecular Neuroscience
  • Sensory Systems

Cite this

Kanan, Y., Hoffhines, A., Rauhauser, A., Murray, A., & Al-Ubaidi, M. R. (2009). Protein tyrosine-O-sulfation in the retina. Experimental Eye Research, 89(4), 559-567.