Plant, Cell and Environment (2015) 38, 655–669 doi: 10.1111/pce.12428
Juncheng Wang1,2*, Yaxiong Meng1,2*, Baochun Li1,3, Xiaole Ma1,2, Yong Lai1,2, Erjing Si1,2, Ke Yang1,2, Xianliang Xu1,2, Xunwu Shang1, Huajun Wang1,2 & Di Wang1,2
1Gansu Provincial Key Lab of Aridland Crop Science/Gansu Key Lab of Crop Improvement & Germplasm Enhancement, Lanzhou 730070, China and 2College of Agronomy and 3College of Life Sciences and Technology, Gansu Agricultural University, Lanzhou 730070, China
ABSTRACT Very little is known about the adaptation mechanism of Chenopodiaceae Halogeton glomeratus, a succulent annual halophyte, under saline conditions. In this study, we investigated the morphological and physiological adaptation mechanisms of seedlings exposed to different concentrations of NaCl treatment for 21 d. Our results revealed that H. glomeratushasarobustabilitytotoleratesalt;itsoptimal growthoccursunderapproximately100 mMNaClconditions. Salt crystals were deposited in water-storage tissue under saline conditions.We speculate that osmotic adjustment may betheprimarymechanismofsalttoleranceinH. glomeratus, which transports toxic ions such as sodium into specific saltstorage cells and compartmentalizes them in large vacuoles tomaintainthewatercontentoftissuesandthesucculenceof theleaves.Toinvestigatethemolecularresponsemechanisms to salt stress in H. glomeratus, we conducted a comparative proteomic analysis of seedling leaves that had been exposed to 200 mM NaCl for 24 h, 72 h and 7 d. Forty-nine protein spots, exhibiting significant changes in abundance after stress, were identified using matrix-assisted laser desorption ionization tandem time-of-flight mass spectrometry (MALDI-TOF/TOF MS/MS) and similarity searches across ESTdatabaseofH. glomeratus.Thesestress-responsiveproteins were categorized into nine functional groups, such as photosynthesis, carbohydrate and energy metabolism, and stress and defence response.
Key-words: EST database; physiology; proteomic; salinity; tolerance.