Photoreceptor pathology in the X-linked retinoschisis (XLRS) mouse results in delayed rod maturation and impaired light driven transducin translocation

Lucia Ziccardi, Camasamudram Vijayasarathy, Ronald A. Bush, Paul A. Sieving

Research output: Contribution to journalArticle


Light-activated movement of transducin-a (Gαt1) from rod photoreceptor outer segments (ROS) into inner segments (IS) enables rods to rapidly adapt to changes in light intensity. The threshold light intensity at which Gat1 translocates from ROS into IS is primarily determined by the rates of activation and inactivation of Gαt1. Loss- of- expression of the retina specific cell surface protein, retinoschsin (Rs1-KO), led to a dramatic 3–10 fold increase, depending on age, in the luminance threshold for transducin translocation from ROS into IS compared with wild-type control. In contrast, arrestin translocated from IS into ROS at the same light intensity both in WT and Rs1-KO mice. Biochemical changes, including reduced transducin protein levels and enhanced transducin GTPase activity, explain the shift in light intensity threshold for Gat1 translocation in Rs1-KO mice. These changes in Rs1-KO mice were also associated with age related alterations in photoreceptor morphology and transcription factor expression that suggest delayed photoreceptor maturation.

Original languageEnglish
Pages (from-to)559-566
Number of pages8
JournalAdvances in Experimental Medicine and Biology
Publication statusPublished - 2014



  • Arrestin
  • Photoreceptors
  • Retinoschisis
  • Transducin
  • Translocation

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Medicine(all)

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