title: Isolation and characterization of a myo-inositol 1-phosphate synthase cDNA from developing sesame (Sesamum indicum L.) seeds: functional and differential expression, and salt-induced transcription during germination.
abstract: A cDNA (SeMIPS1) encoding myo-inositol 1-phosphate synthase (EC 5.5.1.4) (MIPS) has been characterized from sesame (Sesamum indicum L. cv. Dan-Baek) seeds and its functional expression analyzed. The SeMIPS1 protein was highly homologous with those from other plant species (88-94%), while a much lower degree of sequence homology (53-62%) was found with other organisms such as humans, mouse, algae, yeast, Drosophila, bacteria and other prokaryotes. A yeast-based complementation assay in yeast mutants containing a disrupted INO1gene for yeast MIPS confirmed that the SeMIPS1 gene encodes a functional MIPS. Phylogenetic analysis suggested that the SeMIPS1 gene diverged as a different subfamily or family member. Southern hybridization revealed several copies of the SeMIPS1 gene present in the sesame genome and northern blotting indicated that expression of the SeMIPS1gene may be organ specific. Salt stress during sesame seed germination had an adverse influence on transcription of SeMIPS1and greatly reduced transcript levels as the duration of exposure to a saline environment increased and NaCl concentration increased. Germination initiation of sesame seeds was severely delayed as NaCl level increased. These results suggest that expression of SeMIPS1 is down-regulated by salt stress during sesame seed germination.
authors.affiliation: Faculty of Life Science and Resources, Dong-A University, 840, Ha-Dan-Dong, Sa-Ha-Gu, Pusan 604-714, South Korea.
authors.forename: Jae-An
authors.initials: JA
authors.lastname: Chun
authors.forename: Un-Ho
authors.initials: UH
authors.lastname: Jin
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Lee
authors.forename: Young-Byung
authors.initials: YB
authors.lastname: Yi
authors.forename: Nam-In
authors.initials: NI
authors.lastname: Hyung
authors.forename: Myung-Hwa
authors.initials: MH
authors.lastname: Kang
authors.forename: Jae-Ho
authors.initials: JH
authors.lastname: Pyee
authors.forename: Mi Chung
authors.initials: MC
authors.lastname: Suh
authors.forename: Churl-Whan
authors.initials: CW
authors.lastname: Kang
authors.forename: Hong-Yeol
authors.initials: HY
authors.lastname: Seo
authors.forename: Shin-Woo
authors.initials: SW
authors.lastname: Lee
authors.forename: Chung-Han
authors.initials: CH
authors.lastname: Chung
mesh_terms: D000595:Amino Acid Sequence; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005816:Genetic Complementation Test; D018525:Germination / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D009154:Mutation; D007296:Myo-Inositol-1-Phosphate Synthase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012639:Seeds / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D017422:Sequence Analysis, DNA; D031685:Sesamum / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D018076:DNA, Complementary; D010940:Plant Proteins; D012965:Sodium Chloride; D007296:Myo-Inositol-1-Phosphate Synthase