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

We isolated a mutant of Saccharomyces cerevisiae defective in the formation of phosphatidylcholine via methylation of phosphatidylethanolamine. The mutant synthesized phosphatidylcholine at a reduced rate and accumulated increased amounts of methylated phospholipid intermediates. It was also found to be auxotrophic for inositol and allelic to an existing series of ino4 mutants. The ino2 and ino4 mutants, originally isolated on the basis of an inositol requirement, are unable to derepress the cytoplasmic enzyme inositol-1-phosphate synthase (myo-inositol-1-phosphate synthase; EC 5.5.1.4). The INO4 and INO2 genes were, thus, previously identified as regulatory genes whose wild-type product is required for expression of the INO1 gene product inositol-1-phosphate synthase (T. Donahue and S. Henry, J. Biol. Chem. 256:7077-7085, 1981). In addition to the identification of a new ino4-allele, further characterization of the existing series of ino4 and ino2 mutants, reported here, demonstrated that they all have a reduced capacity to convert phosphatidylethanolamine to phosphatidylcholine. The pleiotropic phenotype of the ino2 and ino4 mutants described in this paper suggests that the INO2 and INO4 loci are involved in the regulation of phospholipid methylation in the membrane as well as inositol biosynthesis in the cytoplasm.

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Characterization of Trehalose-6-phosphate Synthase and Trehalose-6-phosphate Phosphatase Genes and Analysis of its Differential Expression in Maize (Zea mays) Seedlings under Drought Stress

Plants ◽

10.3390/plants9030315 ◽

2020 ◽

Vol 9 (3) ◽

pp. 315 ◽

Cited By ~ 1

Author(s):

Phamela Acosta-Pérez ◽

Bianka Dianey Camacho-Zamora ◽

Edward A. Espinoza-Sánchez ◽

Guadalupe Gutiérrez-Soto ◽

Francisco Zavala-García ◽

...

Keyword(s):

Drought Stress ◽

Differential Expression ◽

Extreme Temperature ◽

Amino Acid Sequences ◽

Maize Seedlings ◽

Resistant Lines ◽

Highly Sensitive ◽

Catalytic Sites ◽

Phosphate Synthase

Maize is the most important crop around the world and it is highly sensitive to abiotic stress caused by drought, excessive salinity, and extreme temperature. In plants, trehalose has been widely studied for its role in plant adaptation to different abiotic stresses such as drought, high and low temperature, and osmotic stress. Thus, the aim of this work was to clone and characterize at molecular level the trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) genes from maize and to evaluate its differential expression in maize seedlings under drought stress. To carry out this, resistant and susceptible maize lines were subjected to drought stress during 72 h. Two full-length cDNAs of TPS and one of TPP were cloned and sequenced. Then, TPS and TPP amino acid sequences were aligned with their homologs from different species, showing highly conserved domains and the same catalytic sites. Relative expression of both genes was evaluated by RT-qPCR at different time points. The expression pattern showed significant induction after 0.5 h in resistant lines and after two to four hours in susceptible plants, showing their participation in drought stress response.

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Isolation and characterization of sucrose phosphate synthase promoter from cotton (Gossypium hirsutum L.)

Australian Journal of Crop Science ◽

10.21475/ajcs.17.11.06.p365 ◽

2017 ◽

Vol 11 (06) ◽

pp. 668-675

Author(s):

Nadia Iqbal ◽

◽

Muhammad Asif ◽

Amara Masood ◽

Rubab Zahra Naqvi ◽

...

Keyword(s):

Gossypium Hirsutum ◽

Sucrose Phosphate Synthase ◽

Gossypium Hirsutum L ◽

Isolation And Characterization ◽

Sucrose Phosphate ◽

Phosphate Synthase

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Myo-inositol content in pteridophytes and the isolation and characterization of L-myo-inositol-1-phosphate synthase from Diplopterygium glaucum

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202006000200005 ◽

2006 ◽

Vol 18 (2) ◽

pp. 291-298 ◽

Cited By ~ 4

Author(s):

D. R. Chhetri ◽

A. K. Mukherjee ◽

J. Adhikari

Keyword(s):

De Novo ◽

Deae Cellulose ◽

Normal Growth ◽

Apparent Molecular Weight ◽

Life Forms ◽

Partial Purification ◽

Ph Optimum ◽

Inositol 1 ◽

Isolation And Characterization ◽

Phosphate Synthase

Myo-inositol is involved in normal growth and development of all living organisms and L-myo-inositol-1-phosphate synthase (MIPS; EC: 5.5.1.4) is responsible for its de novo synthesis. This enzyme has been reported for a number of life forms including plants, animals and bacteria. In the present study free myo-inositol has been detected in the common pteridophytes found in the Darjeeling Himalayas and the enzyme, L-myo-inositol-1-phosphate synthase has been partially purified from Diplopterygium glaucum (Thunb.) Nakai. A crude homogenate from the reproductive pinnules of D. glaucum was subjected to streptomycin sulphate precipitation and 0-70% ammonium sulphate fractionation followed by successive chromatography through DEAE-cellulose, Hexylagarose and BioGel A-0.5m columns. This resulted in a partial purification of the enzyme of about 81-fold with 13.5% recovery. The pteridophytic MIPS specifically utilized D-glucose-6-phosphte and NAD+ as its substrate and co-factor, respectively. It shows a pH optimum between 7.0 and 7.5 while the temperature maximum was 30 °C. The enzyme activity was stimulated by NH4+, slightly inhibited by Na+, Ba2+ and Cd2+, and strongly inhibited by Li+, Zn2+ and Hg2+. EDTA, pCMB and some substrate isomers like glucose-1-phosphate, fructose-6-phosphte and galactose-6-phosphate were inhibitory to the enzyme. The apparent molecular weight of the native D. glaucum MIPS was determined to be approximately 171 kDa.

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