Messenger RNA stockpile of cyclin B, insulin-like growth factor I, insulin-like growth factor II, insulin-like growth factor receptor Ib, and p53 in the rainbow trout oocyte in relation with developmental competence

2003 ◽  
Vol 67 (2) ◽  
pp. 127-135 ◽  
Author(s):  
Sandrine Aegerter ◽  
Bernard Jalabert ◽  
Julien Bobe
Keyword(s):  
Rainbow Trout ◽  
Growth Factor ◽  
Messenger Rna ◽  
Growth Factor Receptor ◽  
Developmental Competence ◽  
Cyclin B ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Factor Ii ◽  
Growth Factor I

Mutants of human insulin-like growth factor I with reduced affinity for the type 1 insulin-like growth factor receptor

Biochemistry ◽  
1988 ◽  
Vol 27 (9) ◽  
pp. 3229-3233 ◽  
Author(s):  
Margaret A. Cascieri ◽  
Gary G. Chicchi ◽  
Joy Applebaum ◽  
Nancy S. Hayes ◽  
Barbara G. Green ◽  
...  
Keyword(s):  
Growth Factor ◽  
Human Insulin ◽  
Growth Factor Receptor ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Growth Factor I

Effects of insulin-like growth factor-I, insulin, and leucine on protein turnover and ubiquitin ligase expression in rainbow trout primary myocytes

2010 ◽  
Vol 298 (2) ◽  
pp. R341-R350 ◽  
Author(s):  
Beth M. Cleveland ◽  
Gregory M. Weber
Keyword(s):  
Protein Synthesis ◽  
Rainbow Trout ◽  
Growth Factor ◽  
Protein Degradation ◽  
Ubiquitin Ligase ◽  
Protein Turnover ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Igf I ◽  
Growth Factor I

The effects of insulin-like growth factor-I (IGF-I), insulin, and leucine on protein turnover and pathways that regulate proteolytic gene expression and protein polyubiquitination were investigated in primary cultures of 4-day-old rainbow trout myocytes. Supplementing media with 100 nM IGF-I increased protein synthesis by 13% ( P < 0.05) and decreased protein degradation by 14% ( P < 0.05). Treatment with 1 μM insulin increased protein synthesis by 13% ( P < 0.05) and decreased protein degradation by 17% ( P < 0.05). Supplementing media containing 0.6 mM leucine with an additional 2.5 mM leucine did not increase protein synthesis rates but reduced rates of protein degradation by 8% ( P < 0.05). IGF-I (1 nM–100 nM) and insulin (1 nM-1 μM) independently reduced the abundance of ubiquitin ligase mRNA in a dose-dependent manner, with maximal reductions of ∼70% for muscle atrophy F-box (Fbx) 32, 40% for Fbx25, and 25% for muscle RING finger-1 (MuRF1, P < 0.05). IGF-I and insulin stimulated phosphorylation of FOXO1 and FOXO4 ( P < 0.05), which was inhibited by the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor wortmannin, and decreased the abundance of polyubiquitinated proteins by 10–20% ( P < 0.05). Supplementing media with leucine reduced Fbx32 expression by 25% ( P < 0.05) but did not affect Fbx25 nor MuRF1 transcript abundance. Serum deprivation decreased rates of protein synthesis by 60% ( P < 0.05), increased protein degradation by 40% ( P < 0.05), and increased expression of all ubiquitin ligases. These data suggest that, similar to mammals, the inhibitory effects of IGF-I and insulin on proteolysis occur via P I3-kinase/protein kinase B signaling and are partially responsible for the ability of these compounds to promote protein accretion.

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