Human heart LIM protein activates atrial-natriuretic-factor gene expression by interacting with the

Bin Zheng1, Mei Han, Jin-Kun Wen

  • 1Hebei Laboratory of Medical Biotechnology, Institute of Basic Medicine, Hebei Medical University, Shijiazhuang 050017, People's Republic of China.

The Biochemical Journal
|October 12, 2007
PubMed

hhLIM [human heart LIM (Lin-11/IsI-1/Mec-3) protein] is a muscle-specific LIM-only protein that consists of two LIM motifs. hhLIM functions as a positive regulator for cardiac hypertrophy. Here we report that hhLIM serves as a cofactor regulating the expression of the ANF (atrial natriuretic factor) gene in H9c2 rat cardiomyoblast cells. We found that hhLIM promoted the expression of the ANF gene in H9c2 cells, but not in A293 human embryonic kidney cells. Furthermore, we showed that hhLIM interacted with Nkx2.5 (a cardiac-restricted transcription factor) in vivo and in vitro using its N-terminal LIM domain and enhanced the binding ability of Nkx2.5 to the NKE (Nkx2.5-binding element) boxes in the ANF promoter. These results suggest that hhLIM promotes the specific expression of the ANF gene by co-operating with Nkx2.5.

Related Concept Videos

Heart Failure II: Pathophysiology01:29

Heart Failure II: Pathophysiology

Systolic Heart Failure and Compensatory MechanismsSystolic heart failure (also termed HFrEF, Heart Failure with Reduced Ejection Fraction) is the most prevalent type of heart filure. It results in a decreased volume of blood being pumped from the ventricle. The aortic arch and carotid sinuses have baroreceptors that detect reduced blood pressure, triggering the sympathetic nervous system (SNS) to release epinephrine and norepinephrine. Initially, this response aims to boost heart rate and...
Pathophysiology of Heart Failure01:17

Pathophysiology of Heart Failure

Heart failure (HF) is a progressive syndrome involving ventricles that leads to inadequate cardiac output. It can be classified based on location and output or ejection fraction. Ejection fraction (EF) is an essential measurement in the diagnosis and surveillance of HF. Reduced EF corresponds to systolic heart failure (HFrEF). However, HF with preserved ejection fraction (HFpEF) is becoming increasingly prevalent. Also known as diastolic HF, this form of HF is related to aging. The...
Heart Failure Drugs: Inhibitors of Renin-Angiotensin System01:26

Heart Failure Drugs: Inhibitors of Renin-Angiotensin System

The activation of the sympathetic nervous system and the renin-angiotensin-aldosterone system (RAAS) contributes to cardiac remodeling, and inhibiting the RAAS is a pharmacological target in heart failure management. As a result, neurohumoral modulation is a crucial treatment principle for managing heart failure. This approach involves using medications like ACE inhibitors (ACEIs), angiotensin receptor blockers (ARBs), β-blockers, mineralocorticoid receptor antagonists (MRAs), and neutral...
Regulation of Heart Rates01:31

Regulation of Heart Rates

The regulation of heart rate is a complex process controlled by the autonomic nervous system (ANS), hormonal influences, and intrinsic cardiac mechanisms. The ANS has two main components: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
The SNS increases heart rate through the release of norepinephrine and epinephrine, which act on beta-1 adrenergic receptors in the heart. This action increases the rate of depolarization in the sinoatrial (SA) node, the heart's...
Hormonal Regulation of Blood Pressure01:17

Hormonal Regulation of Blood Pressure

Endocrinal or hormonal intervention in the cardiovascular system is predominantly exerted by the catecholamines - epinephrine and norepinephrine, as well as a slew of hormones that interact with renal function to modulate blood volume.
Epinephrine and Norepinephrine
The adrenal medulla releases epinephrine and norepinephrine, catecholamines that enhance and extend the sympathetic or "fight or flight" physiological response. These hormones escalate heart rate and the force of contraction while...
Pathophysiology of Cardiac Performance01:29

Pathophysiology of Cardiac Performance

Typical heart performance is influenced by heart rate, rhythm, myocardial contraction, and metabolism or blood flow. The cardiac muscle exhibits distinct electrophysiological features, including pacemaker activity and calcium channel control, which play a vital role in the heart's response to various drugs. The autonomic nervous system, comprising the sympathetic and parasympathetic branches, regulates heart rate. Sympathetic activation increases heart rate, while parasympathetic activation...