scholarly journals Co-regulation of the atrial natriuretic factor and cardiac myosin light chain-2 genes during alpha-adrenergic stimulation of neonatal rat ventricular cells. Identification of cis sequences within an embryonic and a constitutive contractile protein gene which mediate inducible expression.

1991 ◽  
Vol 266 (12) ◽  
pp. 7759-7768
Author(s):  
K U Knowlton ◽  
E Baracchini ◽  
R S Ross ◽  
A N Harris ◽  
S A Henderson ◽  
...  
Keyword(s):  
Light Chain ◽  
Atrial Natriuretic Factor ◽  
Myosin Light Chain ◽  
Protein Gene ◽  
Neonatal Rat ◽  
Cardiac Myosin ◽  
Adrenergic Stimulation ◽  
Ventricular Cells ◽  
Myosin Light Chain 2 ◽  
Stimulation Of

A conserved 28-base-pair element (HF-1) in the rat cardiac myosin light-chain-2 gene confers cardiac-specific and alpha-adrenergic-inducible expression in cultured neonatal rat myocardial cells

1991 ◽  
Vol 11 (4) ◽  
pp. 2273-2281
Author(s):  
H Zhu ◽  
A V Garcia ◽  
R S Ross ◽  
S M Evans ◽  
K R Chien
Keyword(s):  
Transient Expression ◽  
Light Chain ◽  
Myosin Light Chain ◽  
Myocardial Cell ◽  
Inducible Expression ◽  
Neonatal Rat ◽  
Cardiac Myosin ◽  
Myocardial Cells ◽  
Myosin Light Chain 2 ◽  
Regulated Expression

To study the transcriptional regulatory mechanisms which mediate cardiac-specific and inducible expression during myocardial cell hypertrophy, we have extensively characterized the rat cardiac myosin light-chain-2 (MLC-2) gene as a model system. The MLC-2 gene encodes a relatively abundant contractile protein in slow skeletal and cardiac muscle and is upregulated during in vivo cardiac hypertrophy and alpha-adrenergic-mediated hypertrophy of neonatal rat myocardial cells. In transient expression assays employing a series of MLC-2-luciferase constructs, recent studies have identified a 250-bp fragment which is sufficient for both cardiac-specific and alpha-adrenergic-inducible expression. Within this 250-bp fragment lie three regions (HF-1, HF-2, and HF-3), each greater than 10 bp in length, which are conserved between the chicken and rat cardiac MLC-2 genes, suggesting their potential role in the regulated expression of this contractile protein gene. As assessed by substitution mutations within each of the conserved regions, the present study demonstrates that HF-1 and HF-2 are important in both cardiac-specific and inducible expression, while HF-3 has no detectable role in the regulated expression of the MLC-2 gene in transient expression assays. HF-1 sequences confer both cardiac-specific and inducible expression to a neutral promoter-luciferase construct but have no significant effect in the skeletal muscle or nonmuscle cell contexts. Thus, these studies have identified a new cardiac-specific regulatory element (HF-1) which plays a role in both cardiac-specific and inducible expression during myocardial cell hypertrophy.

scholarly journals A conserved 28-base-pair element (HF-1) in the rat cardiac myosin light-chain-2 gene confers cardiac-specific and alpha-adrenergic-inducible expression in cultured neonatal rat myocardial cells.

1991 ◽  
Vol 11 (4) ◽  
pp. 2273-2281 ◽  
Author(s):  
H Zhu ◽  
A V Garcia ◽  
R S Ross ◽  
S M Evans ◽  
K R Chien
Keyword(s):  
Transient Expression ◽  
Light Chain ◽  
Myosin Light Chain ◽  
Myocardial Cell ◽  
Inducible Expression ◽  
Neonatal Rat ◽  
Cardiac Myosin ◽  
Myocardial Cells ◽  
Myosin Light Chain 2 ◽  
Regulated Expression

To study the transcriptional regulatory mechanisms which mediate cardiac-specific and inducible expression during myocardial cell hypertrophy, we have extensively characterized the rat cardiac myosin light-chain-2 (MLC-2) gene as a model system. The MLC-2 gene encodes a relatively abundant contractile protein in slow skeletal and cardiac muscle and is upregulated during in vivo cardiac hypertrophy and alpha-adrenergic-mediated hypertrophy of neonatal rat myocardial cells. In transient expression assays employing a series of MLC-2-luciferase constructs, recent studies have identified a 250-bp fragment which is sufficient for both cardiac-specific and alpha-adrenergic-inducible expression. Within this 250-bp fragment lie three regions (HF-1, HF-2, and HF-3), each greater than 10 bp in length, which are conserved between the chicken and rat cardiac MLC-2 genes, suggesting their potential role in the regulated expression of this contractile protein gene. As assessed by substitution mutations within each of the conserved regions, the present study demonstrates that HF-1 and HF-2 are important in both cardiac-specific and inducible expression, while HF-3 has no detectable role in the regulated expression of the MLC-2 gene in transient expression assays. HF-1 sequences confer both cardiac-specific and inducible expression to a neutral promoter-luciferase construct but have no significant effect in the skeletal muscle or nonmuscle cell contexts. Thus, these studies have identified a new cardiac-specific regulatory element (HF-1) which plays a role in both cardiac-specific and inducible expression during myocardial cell hypertrophy.

scholarly journals A single transcription factor binds to two divergent sequence elements with a common function in cardiac myosin light chain-2 promoter.

1992 ◽  
Vol 12 (3) ◽  
pp. 1107-1116 ◽  
Author(s):  
P Qasba ◽  
E Lin ◽  
M D Zhou ◽  
A Kumar ◽  
M A Siddiqui
Keyword(s):  
Transcription Factor ◽  
Gene Transcription ◽  
Light Chain ◽  
Myosin Light Chain ◽  
Cardiac Myosin ◽  
Divergent Sequence ◽  
Specific Element ◽  
Myosin Light Chain 2 ◽  
Sequence Elements ◽  
Gel Shift

The cardiac myosin light chain-2 (MLC-2) gene promoter contains several positive and negative cis-acting sequences that are involved in the regulation of its expression. We describe here the properties of two activator sequences, elements A and P, and their DNA-binding factors (ABFs). Element A (CCAAAAGTGG), located at -61, has homology with the evolutionarily conserved sequence CC(A/T)6GG, present in the genes of many contractile proteins. Element P (TAACCTTGAAAGC), located 114 bp upstream of element A, is conserved in both chicken and rat cardiac MLC-2 gene promoters. Deletion mutagenesis demonstrated that these two elements are involved in the positive regulation of MLC-2 gene transcription. At least two sequence-specific element A-binding proteins, ABF-1 and ABF-2, were identified by gel shift analysis of the fractionated cardiac nuclear proteins. ABF-1 binds to element A with strict dependence on the internal element A sequence AAAAGT. In contrast, ABF-2 exhibits a relaxed sequence requirement, as it recognizes the consensus CArG and CCAAT box sequences as well. ABF-2 also recognizes the distal element P despite the fact that the sequences of elements A and P are divergent. DNase I footprinting, methylation interference, and gel shift analyses demonstrated unequivocally that the element A-DNA affinity-purified protein ABF-2 binds to element P with sequence specificity. Since both elements A and P play a positive regulatory role in MLC-2 gene transcription and bind to a single protein (ABF-2), it would appear that ABF-2 is a key transcription factor with the ability to recognize divergent sequence elements involved in a common regulatory pathway during myogenesis.

Sign in / Sign up

Export Citation Format

Share Document