title: Spodoptera frugiperda FKBP-46 is a consensus p53 motif binding protein.
abstract: p53 protein, the central molecule of the apoptosis pathway, is mutated in 50% of the human cancers. Of late, p53 homologues have been identified from different invertebrates including Drosophila melanogaster, Caenorhabditis elegans, Squid, and Clams. We report the identification of a p53-like protein in Spodoptera frugiperda (Sf9) insect cells, which is activated during oxidative stress, caused by exposure to UV-B or H(2) O(2) , and binds to p53 consensus DNA binding motifs as well as other p53 cognate motifs. Sf9 p53 motif-binding protein is similar to murine and Drosophila p53 in terms of molecular size, which is around 50-60 kDa, as evident from UV cross-linking, and displays DNA binding characteristics similar to both insect and vertebrate p53 as seen from electrophoretic mobility shift assays. The N-terminal sequencing of the purified Sf9 p53 motif-binding protein reveals extensive homology to the pro-apoptotic FK-506 binding protein (FKBP-46), earlier identified in Sf9 cells as a factor which interacts with murine casein kinase. FKBP, an evolutionarily conserved protein of mammalian origin functions as a pro-apoptotic factor. Identification of FKBP-46 as a novel p53 motif-binding protein in insect cells adds a new facet to our understanding of the mechanisms of apoptosis under oxidative stress in the absence of a typical p53 homologue.
authors.affiliation: Institute of Life Sciences, Hyderabad, Andhra Pradesh 500 046, India.
authors.forename: Krishnaveni
authors.initials: K
authors.lastname: Mohareer
authors.forename: Sudhir
authors.initials: S
authors.lastname: Sahdev
authors.forename: Seyed E
authors.initials: SE
authors.lastname: Hasnain
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D016384:Consensus Sequence; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004330:Drosophila / Q000378:metabolism; D029721:Drosophila Proteins / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D006861:Hydrogen Peroxide / Q000494:pharmacology; D019476:Insect Proteins / Q000302:isolation & purification / Q000378:metabolism*; D059372:Nucleotide Motifs; D018384:Oxidative Stress; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D018411:Spodoptera / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D014466:Ultraviolet Rays
chemical_list: D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D019476:Insect Proteins; D016159:Tumor Suppressor Protein p53; C474203:p53 protein, Drosophila; D006861:Hydrogen Peroxide