The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Tissue-specific regulation of 4E-BP1 and S6K1 phosphorylation by alpha-ketoisocaproate.

The indispensable branched-chain amino acid leucine acts as a key regulator of mRNA translation by modulating the phosphorylation of proteins that represent important control points in translation initiation, including the translational repressor, eukaryotic initiation factor (eIF) 4E-binding protein 1 (4E-BP1) and ribosomal protein S6 kinase (S6K1). In the current study, we compared the effects of L- and D-enantiomers of leucine on the phosphorylation of 4E-BP1 and S6K1. We also assessed whether leucine itself or its metabolite, alpha-ketoisocaproate (alpha-KIC), mediates the effects of leucine. Food-deprived (18 h) rats were orally administered 135 mg/100 g body weight L-leucine, D-leucine or alpha-KIC and were sacrificed after 1 h. L-Leucine administration had an obvious stimulatory effect on the phosphorylation of 4E-BP1 and S6K1 in both skeletal muscle and liver while D-leucine was much less effective, indicating that the effect of leucine is stereospecific. Oral administration of alpha-KIC mimicked the stimulatory effect of L-leucine in skeletal muscle. In contrast to skeletal muscle, provision of alpha-KIC was significantly less effective than L-leucine in the liver. The results showing that the efficacy of L-leucine and alpha-KIC in stimulating phosphorylation of S6K1 and 4E-BP1 is equivalent in skeletal muscle, may be explained by the conversion of alpha-KIC to L-leucine.[1]


  1. Tissue-specific regulation of 4E-BP1 and S6K1 phosphorylation by alpha-ketoisocaproate. Yoshizawa, F., Sekizawa, H., Hirayama, S., Yamazaki, Y., Nagasawa, T., Sugahara, K. J. Nutr. Sci. Vitaminol. (2004) [Pubmed]
WikiGenes - Universities