Proteome response of different chinese fir clones under drought stress
Guochang Ding^1,2,#,Weizhi Guo^1,2,#, Weifeng Xu^3,4, Shaoning Ruan^1,2, Sizu Lin^1,2,* ,Zhijie Liu^1,2, Zhihui Ma^1,2

¹ Fujian Agriculture and Forestry University, Fuzhou 350002, China.
2 Chinese Fir Engineering Research Center of Fujian, Fuzhou, Fujian 350002, China.
³ Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
⁴ School of Life Sciences and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong 999077, Hong Kong.
^*Correspond author: szlin53@126.com .
^#These authors contributed equally to this work

Abstract
Chinese fir is one of the most important commercial tree species in China. Nowadays, frequent seasonal drought has the serious negative effects on Chinese fir production. In this study, under PEG-6000-stimulated drought stress, using FS43 (a drought-tolerant Chinese fir clone) and FS38 (a drought-sensitive Chinese fir clone), we investigated the changes in the Chinese fir leaf proteome in response to drought stress. By using two-dimensional (2D) gel electrophoresis, 24 differentially expressed protein spots were selected. From these, five proteins were identified by tandem mass spectrometry, analysed and classified into 4 catagories. Category 1, photosynthetic light reaction and carbon reaction related enzyme, capture light chlorophyll a/b binding protein and ribulose bisphospahate carboxylase/oxygenase. Category 2, osmotic protection material synthesis related enzyme, muscle alcohol - 1 - phosphate synthetase. Category 3, metabolism related enzyme, granule combined with starch synthase. Category 4, antioxidation closely related enzyme, peroxidase. Our results suggest that 5 proteins may play the important role in the Chinese Fir response to seasonal drought stress.

Key Words: drought; Chinese fir; two-dimensional gel electrophoresis; proteome response