Human Erythrocyte Dematin and Protein 4.2 (Pallidin) Are ATP Binding Proteins
Autor: | Elizabeth Dotimas, Anser C. Azim, Athar H. Chishti, Catherine Korsgren, Carl M. Cohen, Shirin M. Marfatia |
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Rok vydání: | 1996 |
Předmět: |
Recombinant Fusion Proteins
Protein subunit Molecular Sequence Data Polymerase Chain Reaction Biochemistry Conserved sequence Adenosine Triphosphate Humans Amino Acid Sequence Binding site Peptide sequence Conserved Sequence DNA Primers Base Sequence Chemistry Erythrocyte Membrane Microfilament Proteins Peripheral membrane protein Protein primary structure Membrane Proteins Blood Proteins Phosphoproteins Fusion protein Cytoskeletal Proteins Kinetics Mutagenesis Insertional Oligodeoxyribonucleotides Membrane protein Carrier Proteins |
Zdroj: | Biochemistry. 35:3001-3006 |
ISSN: | 1520-4995 0006-2960 |
DOI: | 10.1021/bi951745y |
Popis: | Dematin and protein 4.2 are peripheral membrane proteins associated with the cytoplasmic surface of the human erythrocyte plasma membrane. Isoforms of dematin and protein 4.2 exist in many nonerythroid cells. In solution, dematin is a trimeric protein containing two subunits of 48 kDa and one subunit of 52 kDa. Recent determination of the primary structure of the 52 kDa subunit of dematin showed that it contains an additional 22-amino acid sequence in the headpiece domain. An alignment of the 22-amino acid insertion sequence revealed that the 52 kDa subunit of dematin shares a novel 11-amino acid motif with protein 4.2. In this communication, we report that the conserved 11-amino acid motif in dematin52 and protein 4.2 contains a nucleotide binding P-loop. Direct binding of ATP is demonstrated to the glutathione S-transferase fusion proteins containing corresponding segments of dematin52 and protein 4.2 as well as to purified protein 4.2. The binding of ATP to the recombinant domains of dematin52 and protein 4.2 is specific, saturable, and of high affinity. The nucleotide specificity of the P-loop is restricted to ATP since no detectable binding was observed with GTP. These results show that the 11-amino acid motif provides an ATP binding site in dematin52 and protein 4.2. Although the functional significance of ATP binding is not yet clear, our findings open new perspectives for the function of dematin and protein 4.2 in vivo. |
Databáze: | OpenAIRE |
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