Simultaneous overexpression of Oct4 and Nanog abrogates terminal myogenesis

Autor: Shen Liang Chen, Han Fang Teng, Kuan Chih Lang, Chung Leung Li, Kam Tsun Tang, I. Hsuan Lin, Yi Cheng Huang
Rok vydání: 2009
Předmět:
Pluripotent Stem Cells
Transcriptional Activation
Homeobox protein NANOG
Physiology
Myoblasts
Skeletal
Rex1
Molecular Sequence Data
Muscle Fibers
Skeletal
Mice
SCID
Biology
Muscle Development
Cell Line
Mice
Mice
Inbred NOD
Animals
Cell Lineage
Promoter Regions
Genetic
Transcription factor
reproductive and urinary physiology
Feedback
Physiological
Homeodomain Proteins
Binding Sites
Base Sequence
MEF2 Transcription Factors
Myogenesis
SOXB1 Transcription Factors
Teratoma
Gene Expression Regulation
Developmental
PAX7 Transcription Factor
Nanog Homeobox Protein
Cell Differentiation
Cell Biology
musculoskeletal system
Embryonic stem cell
Molecular biology
Up-Regulation
Cell biology
Myogenic Regulatory Factors
embryonic structures
biological phenomena
cell phenomena
and immunity
PAX7
Stem cell
Octamer Transcription Factor-3
tissues
Zdroj: American Journal of Physiology-Cell Physiology. 297:C43-C54
ISSN: 1522-1563
0363-6143
Popis: Oct4 and Nanog are two embryonic stem (ES) cell-specific transcription factors that play critical roles in the maintenance of ES cell pluripotency. In this study, we investigated the effects of Oct4 and Nanog expression on the differentiation state of myogenic cells, which is sustained by a strong positive feedback loop. Oct4 and Nanog, either independently or simultaneously, were overexpressed in C2C12 myoblasts, and the expression of myogenic lineage-specific genes and terminal differentiation was observed by RT-PCR. Overexpression of Oct4 in C2C12 cultures repressed, while exogenous Nanog did not significantly alter C2C12 terminal differentiation. The expression of Pax7 was reduced in all Oct4-overexpressing myoblasts, and we identified a major Oct4-binding site in the Pax7 promoter. Simultaneous expression of Oct4 and Nanog in myoblasts inhibited the formation of myotubes, concomitant with a reduction in the endogenous levels of hallmark myogenic markers. Furthermore, overexpression of Oct4 and Nanog induced the expression of their endogenous counterparts along with the expression of Sox2. Using mammalian two-hybrid assays, we confirmed that Oct4 functions as a transcriptional repressor whereas Nanog functions as a transcriptional activator during muscle terminal differentiation. Importantly, in nonobese diabetic (NOD) severe combined immunodeficiency (SCID) mice, the pluripotency of C2C12 cells was conferred by overexpression of Oct4 and Nanog. These results suggest that Oct4 in cooperation with Nanog strongly suppresses the myogenic differentiation program and promotes pluripotency in myoblasts.
Databáze: OpenAIRE
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