Regulatory effect of the glial Golli-BG21 protein on the full-length murine small C-terminal domain phosphatase (SCP1, or Golli-interacting protein).
Biochem Biophys Res Commun
; 447(4): 633-7, 2014 May 16.
Article
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| MEDLINE
| ID: mdl-24751520
The gene in the oligodendrocyte lineage (golli) encodes a number of proteins essential for myelination, comprising Golli and classic isoforms that are expressed in a developmentally-regulated manner. The Golli-interacting-protein (GIP) was previously discovered in a search for potential interacting partners of the Golli-isoform BG21, and was realised to be an acidic phosphatase belonging to the family of RNA-polymerase-2, small-subunit, C-terminal phosphatases (viz., SCP1). Here, we refer to this protein as mSCP1/GIP. In subsequent in vitro studies of recombinant murine SCP1/GIP, the inability to produce an active full-length version of the protein under native conditions necessitated the study of a truncated form ΔN-rmSCP1/GIP, but with inconclusive results regarding its interaction with BG21 [13]. We have since developed a new SUMO-expression and purification protocol for the preparation of a functional, full-length mGIP/SCP1, with no additional purification tags. Here, the interaction between mSCP1/GIP (with intact N-terminus) and BG21 is shown to be different than for the truncation mutant studied previously. Specifically, this interaction shows a dual effect on the enzymatic activity of mSCP1/GIP by BG21: BG21 enhanced mSCP1/GIP phosphatase activity (Ka = 30 µM), whereas PKCα-phosphorylated BG21 inhibited its activity (Ki = 2.9 µM), suggesting a potential role of BG21 as a molecular switch ("quick-brake mechanism") on mSCP1/GIP. The successful production of an active, full-length mSCP1/GIP thus demonstrates a role for its N-terminus in regulation of phosphatase activity, in events such as the regulation of transcription in oligodendrocytes.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas Nucleares
/
Proteína Básica de Mielina
/
Proteínas del Tejido Nervioso
Límite:
Animals
Idioma:
En
Revista:
Biochem Biophys Res Commun
Año:
2014
Tipo del documento:
Article
País de afiliación:
Canadá
Pais de publicación:
Estados Unidos