title: A ginseng-specific abundant protein (GSAP) located on the cell wall is involved in abiotic stress tolerance.
abstract: Ginseng ESTs allowed us to identify an unknown transcript which is highly abundant in rhizomes and seeds. We called the cDNA ginseng-specific abundant protein (GSAP), and identified three homologues, GSAP1, GSAP2, and GSAP3. GSAP cDNAs encode a small polypeptide consisting of 121 or 117 amino acids, and GSAP3 shows 87.6% amino acid sequence homology with GSAP1. GSAP transcripts were detected in most plant tissues, but GSAP3 is highly expressed in seeds, and is up-regulated under stressed conditions, water deficit. GSAP3-GFP fusion protein is located in the cell wall when expressed in onion epidermis cells. The transgenic Arabidopsis seedlings which over-expressed GSAP3 grew faster than those of the wild-type plant on the medium containing 300 mM mannitol and 100 mM NaCl. GSAP3 may play a role in altering the characteristics of the cell wall to allow for more tolerance of water deficit stress under abiotic stress conditions.
authors.affiliation: Eugentech Inc. 52 Oun-Dong, Yusong, Daejon 305-333, Republic of Korea.
authors.forename: Young Im
authors.initials: YI
authors.lastname: Ha
authors.forename: Jong Min
authors.initials: JM
authors.lastname: Lim
authors.forename: Suk-Min
authors.initials: SM
authors.lastname: Ko
authors.forename: Jang Ryol
authors.initials: JR
authors.lastname: Liu
authors.forename: Dong-Woog
authors.initials: DW
authors.lastname: Choi
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology; D002473:Cell Wall / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D003681:Dehydration / Q000378:metabolism; D008969:Molecular Sequence Data; D018384:Oxidative Stress / Q000502:physiology*; D005894:Panax / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D010940:Plant Proteins / Q000235:genetics / Q000502:physiology*; D030821:Plants, Genetically Modified; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D020033:Protein Isoforms