Assessing the Biological Activity of the Glucan Phosphatase Laforin

  • Carlos Romá-Mateo
  • Madushi Raththagala
  • Mathew S. Gentry
  • Pascual Sanz
Part of the Methods in Molecular Biology book series (MIMB, volume 1447)


Glucan phosphatases are a recently discovered family of enzymes that dephosphorylate either starch or glycogen and are essential for proper starch metabolism in plants and glycogen metabolism in humans. Mutations in the gene encoding the only human glucan phosphatase, laforin, result in the fatal, neurodegenerative, epilepsy known as Lafora disease. Here, we describe phosphatase assays to assess both generic laforin phosphatase activity and laforin’s unique glycogen phosphatase activity.

Key words

Glycogen Lafora disease Dual-specificity phosphatase 



This study was supported by grants from the Spanish Ministry of Education and Science SAF2014-54604-C3-1-R (P.S.), Generalitat Valenciana (PrometeoII/2014/029) (P.S.), NIH Grants R01NS070899 (M.S.G.), P20GM103486 (M.S.G.), Mizutani Foundation for Glycoscience Award (M.S.G.), and NSF Grant IIA-1355438 (M.S.G.). C.R.-M. was supported by the Saving Lives at Birth Consortium.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Carlos Romá-Mateo
    • 1
    • 4
  • Madushi Raththagala
    • 2
  • Mathew S. Gentry
    • 2
  • Pascual Sanz
    • 3
    • 4
  1. 1.Department of Physiology, School of Medicine and DentistryUniversity of Valencia and FIHCUV-INCLIVAValenciaSpain
  2. 2.Department of Molecular and Cellular Biochemistry, Center for Structural BiologyUniversity of KentuckyLexingtonUSA
  3. 3.Instituto de Biomedicina de ValenciaCSICValenciaSpain
  4. 4.Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER)ValenciaSpain

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