Roles of the 15-kDa selenoprotein (Sep15) in redox homeostasis and cataract development revealed by the analysis of Sep 15 knockout mice

Marina V. Kasaikina, Dmitri E. Fomenko, Vyacheslav M. Labunskyy, Salil A. Lachke, Wenya Qiu, Juliet A. Moncaster, Jie Zhang, Mark W. Wojnarowicz, Sathish Kumar Natarajan, Mikalai Malinouski, Ulrich Schweizer, Petra A. Tsuji, Bradley A. Carlson, Richard L. Maas, Marjorie F. Lou, Lee E. Goldstein, Dolph L. Hatfield, Vadim N. Gladyshev

Research output: Contribution to journalArticle

59 Scopus citations


The 15-kDa selenoprotein (Sep15) is a thioredoxin-like, endoplasmic reticulum-resident protein involved in the quality control of glycoprotein folding through its interaction with UDP-glucose:glycoprotein glucosyltransferase. Expression of Sep15 is regulated by dietary selenium and the unfolded protein response, but its specific function is not known. In this study, we developed and characterized Sep15 KO mice by targeted removal of exon 2 of the Sep15 gene coding for the cysteinerich UDP-glucose:glycoprotein glucosyltransferase-binding domain. These KO mice synthesized a mutant mRNA, but the shortened protein product could be detected neither in tissues nor in Sep15 KO embryonic fibroblasts. Sep15 KO mice were viable and fertile, showed normal brain morphology, and did not activate endoplasmic reticulum stress pathways. However, parameters of oxidative stress were elevated in the livers of these mice. We found that Sep15 mRNA was enriched during lens development. Further phenotypic characterization of Sep15KO mice revealed a prominent nuclear cataract that developed at an early age. These cataracts did not appear to be associated with severe oxidative stress or glucose dysregulation. We suggest that the cataracts resulted from an improper folding status of lens proteins caused by Sep15 deficiency.

Original languageEnglish (US)
Pages (from-to)33203-33212
Number of pages10
JournalJournal of Biological Chemistry
Issue number38
StatePublished - Sep 23 2011


ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this

Kasaikina, M. V., Fomenko, D. E., Labunskyy, V. M., Lachke, S. A., Qiu, W., Moncaster, J. A., Zhang, J., Wojnarowicz, M. W., Natarajan, S. K., Malinouski, M., Schweizer, U., Tsuji, P. A., Carlson, B. A., Maas, R. L., Lou, M. F., Goldstein, L. E., Hatfield, D. L., & Gladyshev, V. N. (2011). Roles of the 15-kDa selenoprotein (Sep15) in redox homeostasis and cataract development revealed by the analysis of Sep 15 knockout mice. Journal of Biological Chemistry, 286(38), 33203-33212.