Identification of calmodulin isoform-specific binding peptides from a phage-displayed random 22-mer peptide library. J Biol Chem 2002 Jun 14;277(24):21630-8
Date
03/20/2002Pubmed ID
11901148DOI
10.1074/jbc.M110803200Scopus ID
2-s2.0-0037077216 (requires institutional sign-in at Scopus site) 30 CitationsAbstract
Plants express numerous calmodulin (CaM) isoforms that exhibit differential activation or inhibition of CaM-dependent enzymes in vitro; however, their specificities toward target enzyme/protein binding are uncertain. A random peptide library displaying a 22-mer peptide on a bacteriophage surface was constructed to screen peptides that specifically bind to plant CaM isoforms (soybean calmodulin (ScaM)-1 and SCaM-4 were used in this study) in a Ca2+-dependent manner. The deduced amino acid sequence analyses of the respective 80 phage clones that were independently isolated via affinity panning revealed that SCaM isoforms require distinct amino acid sequences for optimal binding. SCaM-1-binding peptides conform to a 1-5-10 ((FILVW)XXX(FILV) XXXX(FILVW)) motif (where X denotes any amino acid), whereas SCaM-4-binding peptide sequences conform to a 1-8-14 ((FILVW)XXXXXX(FAILVW)XXXXX(FILVW)) motif. These motifs are classified based on the positions of conserved hydrophobic residues. To examine their binding properties further, two representative peptides from each of the SCaM isoform-binding sequences were synthesized and analyzed via gel mobility shift assays, Trp fluorescent spectra analyses, and phosphodiesterase competitive inhibition experiments. The results of these studies suggest that SCaM isoforms possess different binding sequences for optimal target interaction, which therefore may provide a molecular basis for CaM isoform-specific function in plants. Furthermore, the isolated peptide sequences may serve not only as useful CaM-binding sequence references but also as potential reagents for studying CaM isoform-specific function in vivo.
Author List
Choi JY, Lee SH, Park CY, Heo WD, Kim JC, Kim MC, Chung WS, Moon BC, Cheong YH, Kim CY, Yoo JH, Koo JC, Ok HM, Chi SW, Ryu SE, Lee SY, Lim CO, Cho MJAuthor
Sang H. Lee PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Amino Acid MotifsAmino Acid Sequence
Amino Acids
Animals
Base Sequence
Calmodulin
Cattle
Circular Dichroism
Gene Library
Glutathione Transferase
Humans
Kinetics
Molecular Sequence Data
Peptides
Phosphoric Diester Hydrolases
Protein Binding
Protein Isoforms
Recombinant Fusion Proteins
Sequence Homology, Amino Acid
Spectrometry, Fluorescence