The gene encoding rat phosphoglycerate mutase subunit M: cloning and promoter analysis in skeletal muscle cells.
The expression of the gene encoding the muscle-specific (M)-subunit of phosphoglycerate mutase (PGAM-M) is restricted to adult skeletal and cardiac muscle. In order to study its expression in muscle, the rat PGAM-M gene has been isolated and sequenced. Rat PGAM-M spans about 2.2 kb and is composed of three exons: 442, 181 and 186-bp long, and two introns of 97 bp and 1.3 bp. The analysis of the 5'-flanking region reveals a promoter which contains multiple DNA regulatory elements and constitutes an ideal model to study muscle gene transcriptional regulation. Thus, the elements responsible for rat PGAM-M muscle-specific expression have been identified by transient transfection in chicken embryo primary cultures, using chimeric constructs of the rat promoter linked to a cat reporter gene. Here, we report that in spite of the abundance of E-box motifs in the rat PGAM-M promoter known for their involvement in muscle gene expression, two DNA elements regulate the muscle-specific transcription of rat PGAM-M: an A/T motif, the putative MEF-2-binding site (myocyte-specific enhancer-binding factor 2), and a proximal 27-bp element which is conserved between the rat and human genes. These two elements define a small promoter (170 bp) sufficient to support potent and skeletal-muscle-specific expression. The conserved 27-bp region contains a transcriptional regulatory element able to confer muscle-specific expression when located upstream from a heterologous TATA box.
Ruiz-Lozano
P
P
Departament de Ciències Fisiològiques, Universitat de Barcelona, Spain.
de Lecea
L
L
Buesa
C
C
Pérez de la Osa
P
P
LePage
D
D
Gualberto
A
A
Walsh
K
K
Pons
G
G
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism*; D010736:Phosphoglycerate Mutase / Q000235:genetics*; D011401:Promoter Regions, Genetic; D051381:Rats; D012689:Sequence Homology, Nucleic Acid
D010736:Phosphoglycerate Mutase