Journal of Molecular Neuroscience

, Volume 51, Issue 2, pp 615–628 | Cite as

Alternative Splicing of the Chromodomain Protein Morf4l1 Pre-mRNA Has Implications on Cell Differentiation in the Developing Chicken Retina

  • Henrik Boije
  • Henrik Ring
  • Shahrzad Shirazi Fard
  • Ida Grundberg
  • Mats Nilsson
  • Finn Hallböök


The proliferation, cell cycle exit and differentiation of progenitor cells are controlled by several different factors. The chromodomain protein mortality factor 4-like 1 (Morf4l1) has been ascribed a role in both proliferation and differentiation. Little attention has been given to the existence of alternative splice variants of the Morf4l1 mRNA, which encode two Morf41l isoforms: a short isoform (S-Morf4l1) with an intact chromodomain and a long isoform (L-Morf4l1) with an insertion in or in the vicinity of the chromodomain. The aim of this study was to investigate if this alternative splicing has a function during development. We analysed the temporal and spatial distribution of the two mRNAs and over-expressed both isoforms in the developing retina. The results showed that the S-Morf4l1 mRNA is developmentally regulated. Over-expression of S-Morf4l1 using a retrovirus vector produced a clear phenotype with an increase of early-born neurons: retinal ganglion cells, horizontal cells and cone photoreceptor cells. Over-expression of L-Morf4l1 did not produce any distinguishable phenotype. The over-expression of S-Morf4l1 but not L-Morf4l1 also increased apoptosis in the infected regions. Our results suggest that the two Morf4l1 isoforms have different functions during retinogenesis and that Morf4l1 functions are fine-tuned by developmentally regulated alternative splicing. The data also suggest that Morf4l1 contributes to the regulation of cell genesis in the retina.


Acetylation Avian Chromatin structure Development HAT HDAC Isoform Histon MRG15 MRGX Neuron RCAS Retina Splicing Virus vector 



We thank Karl Wahlin for the gateway-adapted RCAS vector, Pernilla Bjerling for the discussions and input. The work was supported by the Swedish Research Council (20859-01-3, 12187-15-3), Barncancerfonden (PROJ09/038), Ögonfonden, St Eriks ögonsjukhus stipendier and Kronprinsessan Margaretas arbetsnämnd för synskadade.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Henrik Boije
    • 1
  • Henrik Ring
    • 1
  • Shahrzad Shirazi Fard
    • 1
  • Ida Grundberg
    • 2
    • 3
  • Mats Nilsson
    • 2
    • 4
  • Finn Hallböök
    • 1
  1. 1.Department of Neuroscience, BMCUppsala UniversityUppsalaSweden
  2. 2.Department of Immunology, Genetics and Pathology, Rudbeck LaboratoryUppsala UniversityUppsalaSweden
  3. 3.Olink BioscienceUppsalaSweden
  4. 4.Science for Life Laboratory, Department of Biochemistry and BiophysicsStockholm UniversityStockholmSweden

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