Molecular Biology Reports

, Volume 38, Issue 5, pp 2869–2877 | Cite as

A mitochondria-localized glutamic acid-rich protein (MGARP/OSAP) is highly expressed in retina that exhibits a large area of intrinsic disorder

  • Shaoling Qi
  • Yifeng Wang
  • Mingxue Zhou
  • Yunxiao Ge
  • Yongbin Yan
  • Jian Wang
  • Samuel Shao-Min Zhang
  • Shuping ZhangEmail author


Study of retina specific genes would offer insights into retinal diseases and treatment. Based on the information from the gene expression profiles of mouse retinas, we here identified a mitochondria-localized glutamic acid-rich protein (MGARP/OSAP) as one of the highly expressed proteins in retina. Sequence analysis revealed that mouse and rat MGARPs have an extra insertion of four consecutive amino acid repeats at the C-terminus, while other homologues do not. MGARP was demonstrated to be localized to the mitochondria and overexpression of MGARP missing N-terminal region causes severe mitochondrial aggregation, implying an important role of MGARP in maintaining mitochondrial morphology. MGARP is highly expressed in mitochondria-rich layers, including inner segment of the photoreceptor, outer plexiform layer and ganglion cell layers of mouse retina. Far-UV CD spectrum analysis suggested that MGARP exhibits a large area of intrinsic disorder and the unusual position of its Tyr fluorescence suggested that Tyr residues in MGARP might form excimer and exist in an ionized state. These findings implied that MGARP be a good candidate for assembling certain ion channels on mitochondria membrane and have great potential to be involved in retinal energetic metabolism through mitochondria related pathway.


Characterization MGARP Retina Cell localization Expression pattern Preliminary structure 



This work was supported by the following grants: the National Basic Research Program (also called the 973 Program) of China (No. 2006CB705700), the National Natural Science Foundation of China (No. 30671036). We appreciate Dr. Shaoyong Chen (BIDMC, Harvard Medical School) for discussions and reading of the manuscript.

Supplementary material

11033_2010_9948_MOESM1_ESM.doc (380 kb)
Supplementary material 1 (DOC 380 kb)


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Shaoling Qi
    • 1
  • Yifeng Wang
    • 1
  • Mingxue Zhou
    • 1
  • Yunxiao Ge
    • 1
  • Yongbin Yan
    • 1
  • Jian Wang
    • 1
  • Samuel Shao-Min Zhang
    • 2
    • 3
  • Shuping Zhang
    • 1
    Email author
  1. 1.Department of Biological Sciences and Biotechnology, State-Key Lab of Biomembranes and Membrane BiotechnologyTsinghua UniversityBeijingChina
  2. 2.Department of PathologyYale University School of MedicineNew HavenUSA
  3. 3.Pennsylvania State Hershey Medical CenterHersheyUSA

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