laforin; Lafora PTPase; LAFPTPase (EPM2A)

Function

• dual specificity protein phosphatase
• control of glycogen metabolism
  • monitoring for & preventing the formation of poorly branched glycogen molecules (polyglucosans)
• acts as a scaffold protein to facilitate PPP1R3C/PTG ubiquitination by NHLRC1/malin
• forms a complex with NHLRC1/malin & HSP70
  • interacts with NHLRC1/malin (via the NHL repeats)
  • complex suppresses toxicity of misfolded proteins by promoting their degradation through the ubiquitin-proteasome system
  • polyubiquitinated by NHLRC1/malin
• interacts also with PPP1R5, HIRIP5, EPM2AIP1
• binds glycogen & Lafora bodies
• interacts with PPP1R3C

Compartment

• cytoplasm
• isoform 1: primarily associated with polyribosomes at the endoplasmic reticulum, also found at the plasma membrane
• isoform 2: also found in the nucleus

Alternative splicing

named isoforms=4

Expression

• expressed in heart, skeletal muscle, kidney, pancreas, brain

Pathology

• mutations associated with myoclonic epilepsy of Lafora

More general terms

• tyrosine phosphatase (protein tyrosine phosphatate, PTP)

More specific terms

• Laforin, isoform 9 (EPM2A)

Additional terms

• progressive myoclonic epilepsy 2A; myoclonic epilepsy of Lafora (MELF)

Database

• OMIM: https://mirror.omim.org/entry/607566
• OMIM: https://mirror.omim.org/entry/254780
• OMIM: https://mirror.omim.org/entry/607566
• UniProt: http://www.uniprot.org/uniprot/O95278.html