title: Tomato heat stress protein Hsp16.1-CIII represents a member of a new class of nucleocytoplasmic small heat stress proteins in plants.
abstract: We describe a new class of plant small heat stress proteins (sHsps) with dominant nuclear localization (Hsp17-CIII). The corresponding proteins in tomato, Arabidopsis, and rice are encoded by unique genes containing a short intron in the beta4-encoding region of the alpha-crystallin domain (ACD). The strong nuclear localization results from a cluster of basic amino acid residues in the loop between beta5 and beta6 of the ACD. Using yeast 2-hybrid tests, analyses of native complexes of the sHsps, and immunofluorescence data, we demonstrate that, in contrast to earlier observations (Kirschner et al 2000), proteins of the sHsp classes CI, CII, and CIII interact with each other, thereby influencing oligomerization state and intracellular localization.
authors.affiliation: Department of Molecular Cell Biology, Biocenter of the Goethe University, Marie-Curie-Strasse 9, D-60439 Frankfurt/M., Germany.
authors.forename: Masood
authors.initials: M
authors.lastname: Siddique
authors.forename: Markus
authors.initials: M
authors.lastname: Port
authors.forename: Joanna
authors.initials: J
authors.lastname: Tripp
authors.forename: Christian
authors.initials: C
authors.lastname: Weber
authors.forename: Dirk
authors.initials: D
authors.lastname: Zielinski
authors.forename: Raffaella
authors.initials: R
authors.lastname: Calligaris
authors.forename: Sibylle
authors.initials: S
authors.lastname: Winkelhaus
authors.forename: Klaus-Dieter
authors.initials: KD
authors.lastname: Scharf
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D020798:Two-Hybrid System Techniques
chemical_list: D006360:Heat-Shock Proteins