IGF-I, IGF-II, and IGF-receptor-1 transcript and IGF-II protein expression in myostatin knockout mice tissues.
Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry were performed to demonstrate whether a correlation exists between insulin-like growth factors (IGFs)-positive regulators of growth-and myostatin, a negative regulator of muscle growth. IGF-I, -II, and IGF-receptor-1 (IGF-R1) mRNA and IGF-II protein expressions were determined in control and myostatin knockout mice tissues. IGF-I gene expressions were similar between control and knockout mice tissues, whereas IGF-II mRNA levels were significantly higher in myostatin knockout mice kidney and soleus muscles than those of control mice (P <.01). IGF-R1 mRNA levels from control mice heart (P <.05) and kidney (P <.01) were significantly higher than in myostatin knockout mice, whereas levels were lower in pectoralis muscle of control mice than knockout mice (P <.01). The strongly IGF-II-positive cells in soleus muscle were more common in myostatin knockout mice and were seen in a few foci in control mice. IGF-II immunoreactivity in both control and myostatin knockout mice kidneys was localized to the epithelium of renal tubules and collecting ducts. Reciprocal changes in the expression of myostatin and IGF-II and IGF-R1 may underlie normal growth of skeletal muscle and other organs in mammals, and the changes in these tissues associated with disease.
Kocamis
Hakan
H
Division of Histology and Embryology, Kafkas University, Kars, Turkey.
Gahr
Scott A
SA
Batelli
Lori
L
Hubbs
Ann F
AF
Killefer
John
J
D000199:Actins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism; D007150:Immunohistochemistry; D007334:Insulin-Like Growth Factor I / Q000235:genetics* / Q000378:metabolism; D007335:Insulin-Like Growth Factor II / Q000235:genetics / Q000378:metabolism*; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018482:Muscle, Skeletal / Q000166:cytology / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D055435:Myostatin; D009928:Organ Specificity; D012333:RNA, Messenger / Q000378:metabolism*; D017526:Receptor, IGF Type 1 / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000172:deficiency* / Q000235:genetics
D000199:Actins; C525912:Mstn protein, mouse; D055435:Myostatin; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II; D017526:Receptor, IGF Type 1