Role of SLMAP in Endoplasmic Reticulum Stress and Unfolded Protein Response

Cardiac function is regulated by the molecular components of the sarco/endoplasmic reticulum (ER/SR). Disruptions in homeostatic balance of these proteins and calcium regulation results in activation of ER stress response. Sarcolemmal membrane-associated proteins (SLMAPs) are found in cell membrane, SR/ER, and mitochondria. Overexpression of SLMAP in the myocardium has shown to impair excitation-contraction (E-C) coupling in the transgenic (Tg) mice. ER stress response was examined in Tg mice overexpressing SLMAP in the myocardium. In Tg hearts, changes observed in the expression of proteins involved in ER stress were dependent on the age and sex. SLMAP overexpression results in maladaptive ER stress response, as the mice age. Neonatal cardiomyocytes isolated from the Tg hearts showed decreased viability, upregulation of ER stress response proteins, which were sensitized to thapsigargin-induced stress, and desensitized to palmitate-induced oxidative stress. These findings suggest that normal SLMAP levels are important for proper cardiac function, and cell viability.

Grantor dc:publisher

Université d'Ottawa / University of Ottawa

Year dc:date

2013

Author dc:creator

• Mahmood, Ahsan

Contributors dc:contributor

• Tuana, Balwant

• Protein
• SLMAP
• Unfolded Protein Response
• BiP
• ER stress
• ER
• SR
• Transgenic
• mouse
• cardiac function
• heart
• EC coupling

Language dc:language

en

Identifier

http://dx.doi.org/10.20381/ruor-3152

OAI identifier oai:identifier

oai:ruor.uottawa.ca:10393/24399