Why the study?
Does cardiac specific expression of threonine 5 to alanine mutant sarcolipin cause structural remodeling and diastolic dysfunction in a transgenic mouse model?
Does cardiac specific expression of threonine 5 to alanine mutant sarcolipin cause structural remodeling and diastolic dysfunction in a transgenic mouse model?
Threonine 5 is critical for modulating sarcolipin function, and its mutation leads to abnormal calcium handling, cardiac remodeling, and diastolic dysfunction in mice.
SLNT5A mutation impairs diastolic function in mice; leaves open its role in human HFpEF and need for validation.
The functional importance of threonine 5 (T5) in modulating the activity of sarcolipin (SLN), a key regulator of sarco/endoplasmic reticulum (SR) Ca2+ ATPase (SERCA) pump was studied using a transgenic mouse model with cardiac specific expression of threonine 5 to alanine mutant SLN (SLNT5A). In these transgenic mice, the SLNT5A protein replaces the endogenous SLN in atria, while maintaining the total SLN content. The cardiac specific expression of SLNT5A results in severe cardiac structural remodeling accompanied by bi-atrial enlargement. Biochemical analyses reveal a selective downregulation of SR Ca2+ handling proteins and a reduced SR Ca2+ uptake both in atria and in the ventricles. Optical mapping analysis shows slower action potential propagation in the transgenic mice atria. Doppler echocardiography and hemodynamic measurements demonstrate a reduced atrial contractility and an impaired diastolic function. Together, these findings suggest that threonine 5 plays an important role in modulating SLN function in the heart. Furthermore, our studies suggest that alteration in SLN function can cause abnormal Ca2+ handling and subsequent cardiac remodeling and dysfunction.
No takes yet. Share an insight, caveat, or question.
Shanmugam et al. (2015) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: