The HIV integration site favors G at nucleotides immediately adjacent to the attachment sites. The oxidative DNA glycosylases, with the exception of NTH1, all recognize some form of damaged G. Among the most common oxidative base lesions are 8-oxo-G and Fapy-G. It is intriguing that the BER pathway responsible for repair of oxidative damage, largely damaged Gs, appears to be important for HIV integration and that this integration occurs preferentially at Gs. In contrast, BER apparently does not 5-AIQ hydrochloride affect MMLV integration and MMLV has no preference for G/C base pairs at integration sites. Whether BER proteins affect the integration sites of lentiviruses is under investigation. Lafora disease is an autosomal reccessive and fatal form of epilepsy characterized by the presence of cytoplasmatic aggregates of water-insoluble, poorly branched polyglucosans. These accumulate in the central and BMS-646786 peripheral nervous system, among other tissues. However, it is unclear whether the accumulation of Lafora bodies is the cause of the disease or whether Lafora bodies are secondary determinants of a primarily established metabolic alteration. Glycogen homeostasis depends mainly on the activity of enzymes involved in its synthesis and degradation through mechanisms involving phosphorylation. Type 1 protein phosphatase dephosphorylates and activates GS and dephosphorylates and inactivates GPh and glycogen phosphorylase kinase resulting in glycogen accumulation. The action of PP1 is controlled by several glycogen targeting subunits. PTG facilitates binding of PP1 to glycogen and acts as a molecular scaffold assembling PP1 with GS, GPh, and GPK at intracellular glycogen particles. Thus, PTG modulates glycogen accumulation by bringing PP1 to GS for its activation. Here, we report two PTG variants. One of these mutations replaces asparagine for serine at position 249 and shows significant functional implications in glycogen metabolism. Asparagine 249 is a highly conserved amino acid located at the C-terminus of the protein and is surrounded by two aspartic acid residues that are essential for PTG activity since they are involved in the interaction of PTG with glycogenic substrates such as GS and GPh. We provide evidence that thismutant form results in a reduction of interaction with its partners GPh and laforin, and a decreased capacity to induce glycogen synthesis.