title: Isolation and characterization of a carrot nucleolar protein with structural and sequence similarity to the vertebrate PESCADILLO protein.
abstract: The nuclear matrix is involved in many nuclear events, but its protein architecture in plants is still not fully understood. A cDNA clone was isolated by immunoscreening with a monoclonal antibody raised against nuclear matrix proteins of Daucus carota L. Its deduced amino acid sequence showed about 40% identity with the PESCADILLO protein of zebrafish and humans. Primary structure analysis of the protein revealed a Pescadillo N-terminus domain, a single breast cancer C-terminal domain, two nuclear localization signals, and a potential coiled-coil region as also found in animal PESCADILLO proteins. Therefore, we designated this gene DcPES1. Although DcPES1 mRNA was detected in all tissues examined, its levels were highest in tissues with proliferating cells. Immunofluorescence using specific antiserum against the recombinant protein revealed that DcPES1 localized exclusively in the nucleolus. Examination of fusion proteins with green fluorescent protein revealed that the N-terminal portion was important for localization to the nucleoli of tobacco and onion cells. Moreover, when the nuclear matrix of carrot cells was immunostained with an anti-DcPES1 serum, the signal was detected in the nucleolus. Therefore, the DcPES1 protein appears to be a component of or tightly bound to components of the nuclear matrix.
authors.affiliation: Faculty of Bioresource Sciences, Akita Prefectural University, Akita 010-0195, Japan. uken@akita-pu.ac.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Ueda
authors.forename: Zheng-Jun
authors.initials: ZJ
authors.lastname: Xu
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Miyagi
authors.forename: Michiyuki
authors.initials: M
authors.lastname: Ono
authors.forename: Hiroetsu
authors.initials: H
authors.lastname: Wabiko
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Masuda
authors.forename: Masayasu
authors.initials: M
authors.lastname: Inoue
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002466:Cell Nucleolus / Q000378:metabolism; D018076:DNA, Complementary / Q000302:isolation & purification; D018552:Daucus carota / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D006801:Humans; D008969:Molecular Sequence Data; D015530:Nuclear Matrix / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D017386:Sequence Homology, Amino Acid; D040681:Structural Homology, Protein; D013347:Subcellular Fractions / Q000378:metabolism; D014026:Nicotiana / Q000166:cytology; D014714:Vertebrates / Q000378:metabolism*; D015027:Zebrafish
chemical_list: D018076:DNA, Complementary; D009687:Nuclear Proteins; D010940:Plant Proteins