Yuko Tagaya, Aya Osaki, Atsuko Miura, Shuichi Okada, Kihachi Ohshima, Koshi Hashimoto, Masanobu Yamada, Tetsurou Satoh, Hiroyuki Shimizu and Masatomo Mori Pages 997 - 1004 ( 8 )
Nucleobindin-2 is a 420 amino acid EF-hand Ca2+ binding protein that can be further processed to generate an 82 amino terminal peptide termed Nesfatin-1. To examine the function of secreted Nucleobindin-2 in adipocyte differentiation, cultured 3T3-L1 cells were incubated with either 0 or 100 nM of GST, GST-Nucleobindin-2, prior to and during the initiation of adipocyte differentiation. Nucleobindin-2 treatment decreased neutral lipid accumulation (Oil-Red O staining) and expression of several marker genes for adipocyte differentiation (PPARγ, aP2, and adipsin). When Nucleobindin- 2 was constitutively secreted into cultured medium, cAMP content and insulin stimulated CREB phosphorylation were significantly reduced. On the other hand, intracellularly overexpressed Nucleobindin-2 failed to affect cAMP content and CREB phosphorylation. Taken together, these data indicate that secreted Nucleobindin-2 is a suppressor of adipocyte differentiation through inhibition of cAMP production and insulin signal.
Nucleobindin-2, Nesfatin-1, adipogenesis, 3T3-L1, insulin, GST
Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, 3-39- 15 Showa-machi, Maebashi, Gunma, 371-8511, Japan.