Glucose-regulated protein 78 (GRP78) is elevated in embryonic mouse heart and induced following hypoglycemic stress.
This study investigates the distribution and heart levels of glucose regulated protein (GRP) 78 during normal development and in response to hypoglycemia in the mouse. Results demonstrate that GRP78 is strongly expressed with in the heart, neural tube, gut endoderm, somites, and surface ectoderm of mouse embryos during early organogenesis, and GRP78 staining remains prominent in the heart from gestational days 9.5 through 13.5. Cardiac myocytes are the primary site of GRP78 expression within the heart. GRP78 levels are highest in the heart during early organogenesis and levels decrease significantly by the fetal period. GRP78 expression is increased after 24 h of hypoglycemia in the early organogenesis-stage heart. Considering the tissue specific pattern of GRP expression and changes during development of the heart, GRPs may play significant roles in the normal differentiation and development of cardiac tissue. GRP induction may also be involved in hypoglycemia-induced cardiac dysmorphogenesis.
Department of Anatomy, Physiological Sciences, and Radiology, North Carolina State University College of Veterinary Medicine, Raleigh, 27606, USA. Ida_Smoak@ncsu.edu
J A
JA
Barnes
I W
IW
Smoak
D000818:Animals; D000918:Antibody Specificity; D015153:Blotting, Western; D005314:Embryonic and Fetal Development / Q000502:physiology; D000091342:Endoplasmic Reticulum Chaperone BiP; D005260:Female; D005318:Fetal Heart / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D006321:Heart / Q000196:embryology*; D007003:Hypoglycemia / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D011247:Pregnancy; D011817:Rabbits
D000091342:Endoplasmic Reticulum Chaperone BiP; D018840:HSP70 Heat-Shock Proteins; C000717248:Hspa5 protein, mouse; D008565:Membrane Proteins; C018551:glucose-regulated proteins