Molecular cloning and characterization of a cDNA encoding kiwifruit l-myo-inositol-1-phosphate synthase, a key gene of inositol formation
l-myo-inositol-1-phosphate synthase (MIPS; EC 184.108.40.206) is the key enzyme involved in de novo synthesis of myo-inositol, leading to numerous cellular functions. We isolated an open reading frame of Actinidia deliciosa MIPS (AdMIPS), which is 1,533 bp long and codes for 510 amino acids, with a predicted molecular weight of 56.3 kDa. Sequence analysis revealed its high similarity with MIPS proteins from other organisms. Gene expression and enzyme activity were highest in flower and young fruit. Transcription of AdMIPS was also detected in other tissues. Moderate drought drastically induced expression in the leaves whereas salinity stress induced transcription and enzyme activity in the leaves, phloem, and roots with different degrees. However, a longer period of saline exposure suppressed both expression and enzyme activity in all sampled tissues, indicating that AdMIPS is salt-sensitive.
KeywordsActinidia deliciosa Developmental stages Drought Enzyme activity MIPS Salinity
This work was supported by the National Natural Science Foundation of China (30871700). The authors are grateful to Priscilla Licht for help in revising our English composition.
- 1.Majumder AL, Johnson MD, Henry SA (1997) l-myo-Inositol-1-phosphate synthase. Biochim Biophys Acta (BBA)-Lipids and Lipid. Metabolism 1348(1–2):245–256Google Scholar
- 5.Donahue JL, Alford SR, Torabinejad J, Kerwin RE, Nourbakhsh A, Ray WK, Hernick M, Huang X, Lyons BM, Hein PP (2010) The Arabidopsis thaliana myo-inositol 1-phosphate synthase1 gene is required for myo-inositol synthesis and suppression of cell death. Plant Cell 22(3):888–903PubMedCrossRefGoogle Scholar
- 12.Chun JA, Jin UH, Lee JW, Yi YB, Hyung NI, Kang MH, Pyee JH, Suh M, Kang CW, Seo HY (2003) 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. Planta 216(5):874–880PubMedGoogle Scholar
- 14.Das-Chatterjee A, Goswami L, Maitra S, Dastidar K, Ray S, Majumder A (2006) Introgression of a novel salt-tolerant l-myo-inositol 1-phosphate synthase from Porteresia coarctata (Roxb.) Tateoka (PcINO1) confers salt tolerance to evolutionary diverse organisms. FEBS Lett 580(16):3980PubMedCrossRefGoogle Scholar
- 23.Crowhurst RN, Gleave AP, MacRae EA, Ampomah-Dwamena C, Atkinson RG, Beuning LL, Bulley SM, Chagne D, Marsh KB, Matich AJ (2008) Analysis of expressed sequence tags from Actinidia: applications of a cross species EST database for gene discovery in the areas of flavor, health, color and ripening. BMC genomics 9(1):351PubMedCrossRefGoogle Scholar
- 28.Majumder AL, Chatterjee A, Ghosh Dastidar K, Majee M (2003) Diversification and evolution of l-myo-inositol 1-phosphate synthase. FEBS Lett 553(1–2):3–10Google Scholar
- 32.Klages K, Donnison H, Boldingh H, MacRae E (1998) Myo-Inositol is the major sugar in Actinidia arguta during early fruit development. Funct Plant Biol 25(1):61–68Google Scholar