ATF-7, a novel bZIP protein, interacts with the PRL-1 protein-tyrosine phosphatase.
We have identified a novel basic leucine zipper (bZIP) protein, designated ATF-7, that physically interacts with the PRL-1 protein-tyrosine phosphatase (PTPase). PRL-1 is a predominantly nuclear, farnesylated PTPase that has been linked to the control of cellular growth and differentiation. This interaction was initially found using the yeast two-hybrid system. ATF-7 is most closely related to members of the ATF/CREB family of bZIP proteins, with highest homology to ATF-4. ATF-7 homodimers can bind specifically to CRE elements. ATF-7 is expressed in a number of different tissues and is expressed in association with differentiation in the Caco-2 cell model of intestinal differentiation. We have confirmed the PRL-1.ATF-7 interaction and mapped the regions of ATF-7 and PRL-1 important for interaction to ATF-7's bZIP region and PRL-1's phosphatase domain. Finally, we have determined that PRL-1 is able to dephosphorylate ATF-7 in vitro. Further insight into ATF-7's precise cellular roles, transcriptional function, and downstream targets are likely be of importance in understanding the mechanisms underlying the complex processes of maintenance, differentiation, and turnover of epithelial tissues.
Department of Medicine, Division of Gastroenterology, University of Pennsylvania School of Medicine, Philadelphia 19104-6145, USA.
C S
CS
Peters
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X
Liang
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S
Li
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Kannan
Y
Y
Peng
R
R
Taub
R H
RH
Diamond
D051696:Activating Transcription Factors; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D015152:Blotting, Northern; D018938:Caco-2 Cells; D002352:Carrier Proteins / Q000737:chemistry* / Q000378:metabolism*; D018797:Cell Cycle Proteins; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins; D019281:Dimerization; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D017874:Immediate-Early Proteins / Q000378:metabolism*; D016350:Leucine Zippers; D008565:Membrane Proteins; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D009363:Neoplasm Proteins; D010766:Phosphorylation; D011233:Precipitin Tests; D011485:Protein Binding; D017368:Protein Prenylation; D017434:Protein Structure, Tertiary; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D014157:Transcription Factors; D020798:Two-Hybrid System Techniques; D014443:Tyrosine / Q000378:metabolism
C427752:ATF7 protein, human; D051696:Activating Transcription Factors; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D017362:Cyclic AMP Response Element-Binding Protein; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D017874:Immediate-Early Proteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D014157:Transcription Factors; D014443:Tyrosine; D000242:Cyclic AMP; D005982:Glutathione Transferase; C490198:PTP4A1 protein, human; D017027:Protein Tyrosine Phosphatases; C087359:Ptp4a1 protein, mouse