Transient up-regulation of myotonic dystrophy protein kinase-binding protein, MKBP, and HSP27 in the neonatal myocardium.
Myotonic dystrophy protein kinase (DMPK)-binding protein, MKBP, has high homology with a small heat shock protein, HSP27. Western blotting analyses showed that MKBP level in rat heart rapidly increased, with a sharp peak at one week after birth (3-fold the level at the fetus), but that it rapidly decreased (1/10 of peak value at 13 weeks). Human myocardium also showed similar age-dependency. Similar but small increase of HSP27 was observed in the neonatal rat myocardium, but not in constitutive and inducible forms of HSP70. Immunofluorescence analysis localized MKBP at the Z lines and intercalated discs in the rat myocardium. MKBP may protect actin cytoskeleton or other proteins of heart muscle against oxidative stress in the neonate.
Shama
K M
KM
Department of Legal Medicine, Yamaguchi University School of Medicine, Ube, Japan.
Suzuki
A
A
Harada
K
K
Fujitani
N
N
Kimura
H
H
Ohno
S
S
Yoshida
K
K
D000367:Age Factors; D000818:Animals; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D002451:Cell Compartmentation; D005455:Fluorescent Antibody Technique; D055551:HSP27 Heat-Shock Proteins; D006321:Heart / Q000502:physiology; D006352:Heart Ventricles / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D006801:Humans; D007231:Infant, Newborn; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013347:Subcellular Fractions / Q000737:chemistry; D015854:Up-Regulation
D002352:Carrier Proteins; D055551:HSP27 Heat-Shock Proteins; C442250:HSPB2 protein, human; D006360:Heat-Shock Proteins; C486700:Hspb2 protein, rat