Plant Molecular Biology Reporter

, Volume 33, Issue 1, pp 133–142 | Cite as

Isolation and Preliminary Functional Analysis of MxCS2: a Gene Encoding a Citrate Synthase in Malus xiaojinensis

  • De-Guo Han
  • Yan Shi
  • Bing Wang
  • Wei Liu
  • Ze-Yuan Yu
  • Bing-Yu Lv
  • Guo-Hui Yang
Original Paper


Iron (Fe) is one of the essential micronutrients required by all plants. Citric acid (CA) is considered as the chelate substance in the long-distance transport of Fe. In the present study, a gene encoding putative citrate synthase was isolated from Malus xiaojinensis and designated as MxCS2. The MxCS2 gene encodes a protein of 296 amino acid residues with a predicted molecular mass of 33.2 kDa and a theoretical isoelectric point of 7.79. Subcellular localization has revealed that MxCS2 is preferentially localized in the mitochondrion and cytoplasmic membrane. The expression of MxCS2 was enriched in leaf, root, and phloem, which was highly affected by Fe stress and indoleacetic acid treatment in M. xiaojinensis seedlings. When MxCS2 was introduced into Arabidopsis, it promoted the synthesis of citrate synthase and increased CA content. Overexpression of MxCS2 improved the tolerance to Fe stress in transgenic Arabidopsis, but also led to increased fresh weight, root length, CS activity, and contents of chlorophyll, citrate acid, and Fe, especially when dealing with Fe stress.


Iron MxCS2 Strategy I Transgenic Arabidopsis Real-time PCR 





Abscisic acid


Citric acid


Cauliflower mosaic virus


Green fluorescent protein


Indoleacetic acid


Indole-3-butytric acid


Murashige and Skoog medium


Malus xiaojinensis citrate synthase gene 2




Open reading frame

Real-time PCR

Real-time polymerase chain reaction


Wild type



This project was funded by National Natural Science Foundation of China (31301757), China Postdoctoral Science Foundation (2013 M530144), Heilongjiang Postdoctoral Science Foundation (LBH-Z13033), the Doctoral Fund of Northeast Agricultural University (2012RCB09), Scientific Research Fund of Heilongjiang Provincial Education Department and Special Research of Public Sector on Agriculture (201103037).


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of Northeast Region, Ministry of Agriculture/College of HorticultureNortheast Agricultural UniversityHarbinPeople’s Republic of China

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