Open AccessIncrease in p202 Expression during Skeletal Muscle Differentiation: Inhibition of MyoD Protein Expression and Activity by p202
Author(s) -
Bansidhar Datta,
Min Wang,
Sandeep Burma,
Péter Lengyel
Publication year - 1998
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.18.2.1074
Subject(s) - myod , myogenin , myogenesis , microbiology and biotechnology , biology , c2c12 , myod protein , myocyte , skeletal muscle , endocrinology
p202 is a primarily nuclear, interferon-inducible murine protein that is encoded by theIfi 202 gene. Overexpression of p202 in transfected cells retards cell proliferation. p202 modulates the pattern of gene expression by inhibiting the activity of various transcription factors including NF-κB, c-Fos, c-Jun, E2F-1, and p53. Here we report that p202 was constitutively expressed in mouse skeletal muscle and that the levels of 202 RNA and p202 greatly increased during the differentiation of cultured C2C12 myoblasts to myotubes. When overexpressed in transfected myoblasts, p202 inhibited the expression of one muscle protein (MyoD) without affecting the expression of a second one (myogenin). Thus, the decrease in the level of MyoD (but not of myogenin) during muscle differentiation may be the consequence of the increase in p202 level. Overexpressed p202 also inhibited the transcriptional activity of both MyoD and myogenin. This inhibition was correlated with an interaction of p202 with both proteins, as well as the inhibition by p202 of the sequence-specific binding of both proteins to DNA. This inhibition of the expression of MyoD and of the transcriptional activity of MyoD and myogenin may account for the inhibition of the induction of myoblast differentiation by premature overexpression of p202.