Fad24, a mammalian homolog of Noc3p, is a positive regulator in adipocyte differentiation.
Adipocyte differentiation is controlled by complex actions involving gene expression and signal transduction. From metaphase to anaphase, peroxisome proliferator-activated receptor gamma, 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 gamma. 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.
Tominaga
Kei
K
Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, Aichi 467-8603, Japan.
Johmura
Yoshikazu
Y
Nishizuka
Makoto
M
Imagawa
Masayoshi
M
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology* / Q000378:metabolism; D000595:Amino Acid Sequence; D000705:Anaphase; D000818:Animals; D050976:Basic-Leucine Zipper Transcription Factors; D015152:Blotting, Northern; D022762:CCAAT-Enhancer-Binding Proteins / Q000378:metabolism; D018797:Cell Cycle Proteins; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008024:Ligands; D008677:Metaphase; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D029543:Nucleocytoplasmic Transport Proteins / Q000378:metabolism / Q000502:physiology*; D047495:PPAR gamma / Q000378:metabolism; D017434:Protein Structure, Tertiary; D034622:RNA Interference; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism / Q000502:physiology*; D017386:Sequence Homology, Amino Acid; D051780:Sterol Regulatory Element Binding Protein 1; D013347:Subcellular Fractions / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000378:metabolism
D050976:Basic-Leucine Zipper Transcription Factors; D022762:CCAAT-Enhancer-Binding Proteins; D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D008024:Ligands; C429648:NOC3 protein, S cerevisiae; C502216:NOC3L protein, human; C502215:Noc3l protein, mouse; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; D047495:PPAR gamma; D012333:RNA, Messenger; C497387:SREBF1 protein, human; D029701:Saccharomyces cerevisiae Proteins; C497388:Srebf1 protein, mouse; D051780:Sterol Regulatory Element Binding Protein 1; D014157:Transcription Factors; D049452:Green Fluorescent Proteins