The Ankrd2, Cdkn1c and calcyclin genes are under the control of MyoD during myogenic differentiation.
Skeletal muscle development requires the coordinated expression of numerous transcription factors to control the specification of the muscle fate in mesodermal cells and the differentiation of the committed myoblasts into functional contractile fibers. The bHLH transcription factor MyoD plays a key role in these processes, since its forced expression is sufficient to induce the myogenesis in a variety of non-muscle cells in culture. Consistent with this observation, the majority of skeletal muscle genes require MyoD to activate their own transcription. In order to identify novel MyoD-target genes we generated C2C12 MyoD-silenced clones, and used a muscle-specific cDNA microarray to study the induced modifications of the transcriptional profile. Gene expression was analyzed at three different stages in differentiating MyoD(-)C2C12 myoblasts. These microarray data sets identified many additional uncharacterized downstream MyoD transcripts that may play important functions in muscle cell differentiation. Among these genes, we concentrated our study on the cell cycle regulators Cdkn1c and calcyclin and on the muscle-specific putative myogenic regulator Ankrd2. Bioinformatic and functional studies on the promoters of these genes clarified their dependence on MyoD activity. Clues of other regulatory mechanisms that might interact with the principal bHLH transcription factor have been revealed by the unexpected up-regulation in MyoD(-) cells of these novel (and other) target transcripts, at the differentiation stage in which MyoD became normally down-regulated.
Bean
Camilla
C
Dipartimento di Biologia and CRIBI Biotechnology Centre, Università degli Studi di Padova, 35121 Padova, Italy.
Salamon
Michela
M
Raffaello
Anna
A
Campanaro
Stefano
S
Pallavicini
Alberto
A
Lanfranchi
Gerolamo
G
D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics*; D002454:Cell Differentiation; D002460:Cell Line; D050761:Cyclin-Dependent Kinase Inhibitor p57; D015536:Down-Regulation; D005786:Gene Expression Regulation; D020868:Gene Silencing; D017930:Genes, Reporter / Q000235:genetics; D051379:Mice; D008969:Molecular Sequence Data; D032342:Muscle Cells / Q000166:cytology* / Q000378:metabolism*; D009124:Muscle Proteins / Q000235:genetics*; D017570:MyoD Protein / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D000075383:S100 Calcium Binding Protein A6; D009418:S100 Proteins / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
C485877:Ankrd2 protein, mouse; C493965:Cdkn1c protein, mouse; D018797:Cell Cycle Proteins; D050761:Cyclin-Dependent Kinase Inhibitor p57; D009124:Muscle Proteins; D017570:MyoD Protein; D009687:Nuclear Proteins; D012333:RNA, Messenger; D000075383:S100 Calcium Binding Protein A6; D009418:S100 Proteins; C489134:S100a6 protein, mouse