Identification of a rat 30-kDa protein recognized by the antibodies to a recombinant rat cutaneous fatty acid-binding protein as a 14-3-3 protein.
Immunoblot analysis with polyclonal antibodies raised against a recombinant rat cutaneous fatty acid-binding protein revealed a 30-kDa protein other than the 15-kDa fatty acid-binding protein in rat skin cytosol. This protein was present in a number of rat organs and in mouse 3T3 L1 cells. The amino acid sequences of the enzymatic peptides of the 30-kDa protein extracted from SDS-PAGE gels suggested that it was a mixture of the subunits of the eukaryotic signaling molecule, 14-3-3 protein. Glutathione S-transferase fusion proteins of 14-3-3 protein subunits were examined for cross-reaction by Western blotting, and the epsilon-subunit alone was found to be immunoreactive, so far as tested. It is likely that the 30-kDa protein detected in the rat tissues by the antibodies is the 14-3-3 protein epsilon-subunit. Although there is no apparent sequence similarity between the fatty acid-binding protein and the 14-3-3 protein subunit, they appear to share a common structural element recognized by the antibodies. Since 14-3-3 proteins and fatty acid-binding proteins are known to interact with a wide variety of cellular proteins, the presence of a common local structure might mutually modulate such interactions.
Odani
S
S
Department of Biology, Faculty of Science, Niigata University, Ikarashi Niigata 950-2181, Japan. sodani@sc.niigata-u.ac.jp
Nakamura
J
J
Sato
T
T
Fujii
H
H
D048948:14-3-3 Proteins; D000818:Animals; D000906:Antibodies / Q000378:metabolism*; D015153:Blotting, Western / Q000379:methods; D001921:Brain / Q000378:metabolism; D002352:Carrier Proteins / Q000276:immunology / Q000378:metabolism*; D003429:Cross Reactions; D004817:Epidermis / Q000737:chemistry* / Q000378:metabolism; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005260:Female; D008099:Liver / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000276:immunology; D008297:Male; D051379:Mice; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins; D020539:Sequence Analysis, Protein; D014446:Tyrosine 3-Monooxygenase / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism
D048948:14-3-3 Proteins; D000906:Antibodies; D002352:Carrier Proteins; C082667:Fabp5 protein, mouse; C086936:Fabp7 protein, mouse; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; D014446:Tyrosine 3-Monooxygenase