Limits...
NF-kappaB mediates the transcription of mouse calsarcin-1 gene, but not calsarcin-2, in C2C12 cells.

Wang H, Yang S, Yang E, Zhu Z, Mu Y, Feng S, Li K - BMC Mol. Biol. (2007)

Bottom Line: In addition, the overexpression of NFATc4 induces both the CS-1 and CS-2 promoters, whereas MEF2C only activates CS-1.These results provide new insights into the molecular mechanisms governing transcription in specific muscle fibre cells.The calsarcins may also serve as a valuable mechanistic tool to better understand the regulation of calcineurin signalling during muscle differentiation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Gene and Cell Engineering, State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China. muwhy@hotmail.com <muwhy@hotmail.com>

ABSTRACT

Background: The calsarcins comprise a novel family of muscle-specific calcineurin-interaction proteins that play an important role in modulating both the function and substrate specificity of calcineurin in muscle cells. The expression of calsarcin-1 (CS-1) is restricted to slow-twitch skeletal muscle fibres, whereas that of both calsarcin-2 (CS-2) and calsarcin-3 (CS-3) is enriched in fast-twitch fibres. However, the transcriptional control of this selective expression has not been previously elucidated.

Results: Our real-time RT-PCR analyses suggest that the expression of CS-1 and CS-2 is increased during the myogenic differentiation of mouse C2C12 cells. Promoter deletion analysis further suggests that an NF-kappaB binding site within the CS-1 promoter is responsible for the up-regulation of CS-1 transcription, but no similar mechanism was evident for CS-2. These findings are further supported by the results of EMSA analysis, as well as by overexpression and inhibition experiments in which NF-kappaB function was blocked by treatment with its inhibitor, PDTC. In addition, the overexpression of NFATc4 induces both the CS-1 and CS-2 promoters, whereas MEF2C only activates CS-1.

Conclusion: Our present data suggest that NF-kappaB is required for the transcription of mouse CS-1 but not CS-2, and that the regulation of the calsarcins is mediated also by the NFAT and MEF2 transcription factors. These results provide new insights into the molecular mechanisms governing transcription in specific muscle fibre cells. The calsarcins may also serve as a valuable mechanistic tool to better understand the regulation of calcineurin signalling during muscle differentiation.

Show MeSH

Related in: MedlinePlus

Real-time PCR analysis of CS1 and CS 2 mRNA expression during the myogenic differentiation of C2C12 cells (day 0 to day 7). Values are expressed as ratios of the basal transcription levels on culture day 0 for CS2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC1828060&req=5

Figure 2: Real-time PCR analysis of CS1 and CS 2 mRNA expression during the myogenic differentiation of C2C12 cells (day 0 to day 7). Values are expressed as ratios of the basal transcription levels on culture day 0 for CS2.

Mentions: Real-time PCR analysis was performed to determine the relative mRNA expression levels of both the mouse CS-1 and CS-2 genes during myoblast differentiation in C2C12 cells. Specific primers corresponding to the two genes were designed and the housekeeping gene β-actin was used as a control. We subsequently found that the CS-1 and CS-2 transcript levels were both low at the myoblast stage. CS-1 mRNA expression increases markedly, however, during the first two days of differentiation and is then maintained at relatively abundant levels throughout this process. In contrast, the CS-2 transcript levels remain low throughout myogenic differentiation (Fig. 2).


NF-kappaB mediates the transcription of mouse calsarcin-1 gene, but not calsarcin-2, in C2C12 cells.

Wang H, Yang S, Yang E, Zhu Z, Mu Y, Feng S, Li K - BMC Mol. Biol. (2007)

Real-time PCR analysis of CS1 and CS 2 mRNA expression during the myogenic differentiation of C2C12 cells (day 0 to day 7). Values are expressed as ratios of the basal transcription levels on culture day 0 for CS2.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC1828060&req=5

Figure 2: Real-time PCR analysis of CS1 and CS 2 mRNA expression during the myogenic differentiation of C2C12 cells (day 0 to day 7). Values are expressed as ratios of the basal transcription levels on culture day 0 for CS2.
Mentions: Real-time PCR analysis was performed to determine the relative mRNA expression levels of both the mouse CS-1 and CS-2 genes during myoblast differentiation in C2C12 cells. Specific primers corresponding to the two genes were designed and the housekeeping gene β-actin was used as a control. We subsequently found that the CS-1 and CS-2 transcript levels were both low at the myoblast stage. CS-1 mRNA expression increases markedly, however, during the first two days of differentiation and is then maintained at relatively abundant levels throughout this process. In contrast, the CS-2 transcript levels remain low throughout myogenic differentiation (Fig. 2).

Bottom Line: In addition, the overexpression of NFATc4 induces both the CS-1 and CS-2 promoters, whereas MEF2C only activates CS-1.These results provide new insights into the molecular mechanisms governing transcription in specific muscle fibre cells.The calsarcins may also serve as a valuable mechanistic tool to better understand the regulation of calcineurin signalling during muscle differentiation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Gene and Cell Engineering, State Key Laboratory of Animal Nutrition, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China. muwhy@hotmail.com <muwhy@hotmail.com>

ABSTRACT

Background: The calsarcins comprise a novel family of muscle-specific calcineurin-interaction proteins that play an important role in modulating both the function and substrate specificity of calcineurin in muscle cells. The expression of calsarcin-1 (CS-1) is restricted to slow-twitch skeletal muscle fibres, whereas that of both calsarcin-2 (CS-2) and calsarcin-3 (CS-3) is enriched in fast-twitch fibres. However, the transcriptional control of this selective expression has not been previously elucidated.

Results: Our real-time RT-PCR analyses suggest that the expression of CS-1 and CS-2 is increased during the myogenic differentiation of mouse C2C12 cells. Promoter deletion analysis further suggests that an NF-kappaB binding site within the CS-1 promoter is responsible for the up-regulation of CS-1 transcription, but no similar mechanism was evident for CS-2. These findings are further supported by the results of EMSA analysis, as well as by overexpression and inhibition experiments in which NF-kappaB function was blocked by treatment with its inhibitor, PDTC. In addition, the overexpression of NFATc4 induces both the CS-1 and CS-2 promoters, whereas MEF2C only activates CS-1.

Conclusion: Our present data suggest that NF-kappaB is required for the transcription of mouse CS-1 but not CS-2, and that the regulation of the calsarcins is mediated also by the NFAT and MEF2 transcription factors. These results provide new insights into the molecular mechanisms governing transcription in specific muscle fibre cells. The calsarcins may also serve as a valuable mechanistic tool to better understand the regulation of calcineurin signalling during muscle differentiation.

Show MeSH
Related in: MedlinePlus