Fad24, a mammalian homolog of Noc3p, is a positive regulator in adipocyte differentiation
Fad24, a mammalian homolog of Noc3p, is a positive regulator in adipocyte differentiation
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DOI：
10.1242/jcs.01546
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发表时间：
2004-12
影响因子：
4
通讯作者：
K. Tominaga;Yoshikazu Johmura;M. Nishizuka;M. Imagawa
中科院分区：
文献类型：
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作者：
K. Tominaga;Yoshikazu Johmura;M. Nishizuka;M. Imagawa
脂肪细胞的分化是由基因表达和信号转导的复杂作用控制的。从中期到后期，过氧化物酶体增殖物激活受体γ、CCAAT/增强子结合蛋白家族和固醇调节元件结合蛋白-1已知作为主调节剂起作用。然而，触发分化起始的最早步骤的机制仍然未知。在以前的报告中，我们已经分离出一些基因，其表达在小鼠3 T3-L1前脂肪细胞系分化的早期阶段增加。在这里，我们报告的全长cDNA的克隆和以前分离的一个未知的基因，命名为fad 24（脂肪细胞分化因子24）的表征。Fad 24编码由807个氨基酸组成的蛋白质。推导的氨基酸序列具有碱性亮氨酸拉链基序和NOC结构域。用诱导剂刺激后，fad 24的表达被迅速诱导。此外，fad 24在NIH-3 T3细胞中的过表达在过氧化物酶体增殖物激活受体γ的配体存在下促进脂肪形成。FAD 24定位于细胞核中，尤其是在核斑点内。由于核斑点作为新生转录和前体mRNA剪接机制发挥作用，因此FAD 24可能作为转录和/或前体mRNA剪接的组分之一发挥作用，并正调控脂肪细胞分化。
Adipocyte differentiation is controlled by complex actions involving gene expression and signal transduction. From metaphase to anaphase, peroxisome proliferator-activated receptor γ, the CCAAT/enhancer-binding protein family and sterol regulatory element-binding protein-1 are known to function as master regulators. However, the mechanism underlying the earliest step, which triggers the initiation of differentiation, remains unknown. In previous reports, we have isolated a number of genes, whose expression increases in the early stage of differentiation in the mouse 3T3-L1 preadipocyte cell line. Here we report the cloning of the full-length cDNA and characterization of an unknown gene isolated previously and named fad24 (factor for adipocyte differentiation 24). Fad24 encodes a protein consisting of 807 amino acids. The deduced amino acid sequence was shown to have a basic leucine zipper motif and a NOC domain. Expression of fad24 was rapidly induced after stimulation with inducers. Furthermore, overexpression of fad24 in NIH-3T3 cells promoted adipogenesis in the presence of a ligand for peroxisome proliferator-activated receptor γ. FAD24 localizes in the nucleus, especially within nuclear speckles. As the nuclear speckle functions as a nascent transcription and pre-mRNA splicing machinery, there is a possibility that FAD24 functions as one of the components for transcription and/or pre-mRNA splicing and positively regulates adipocyte differentiation.