Expression profiling of the 14-3-3 gene family in response to salt stress and potassium and iron deficiencies in young tomato (Solanum lycopersicum) roots: analysis by real-time RT-PCR.
BACKGROUND AND AIMS Mineral nutrient deficiencies and salinity constitute major limitations for crop plant growth on agricultural soils. 14-3-3 proteins are phosphoserine-binding proteins that regulate the activities of a wide array of targets via direct protein-protein interactions and may play an important role in responses to mineral nutrients deficiencies and salt stress. In the present study, the expression profiling of the 14-3-3 gene family in response to salt stress and potassium and iron deficiencies in young tomato (Solanum lycopersicum) roots was investigated in order to analyse the 14-3-3 roles of the proteins in these abiotic stresses.


METHODS
Sequence identities and phylogenetic tree creation were performed using DNAMAN version 4.0 (Lynnon Biosoft Company). Real-time RT-PCR was used to examine the expression of each 14-3-3 gene in response to salt stress and potassium and iron deficiencies in young tomato roots.


RESULTS
The phylogenetic tree shows that the 14-3-3 gene family falls into two major groups in tomato plants. By using real-time RT-PCR, it was found that (a) under normal growth conditions, there were significant differences in the mRNA levels of 14-3-3 gene family members in young tomato roots and (b) 14-3-3 proteins exhibited diverse patterns of gene expression in response to salt stress and potassium and iron deficiencies in tomato roots.


CONCLUSIONS
The results suggest that (a) 14-3-3 proteins may be involved in the salt stress and potassium and iron deficiency signalling pathways in young tomato roots, (b) the expression pattern of 14-3-3 gene family members in tomato roots is not strictly related to the position of the corresponding proteins within a phylogenetic tree, (c) gene-specific expression patterns indicate that isoform-specificity may exist in the 14-3-3 gene family of tomato roots, and (d) 14-3-3 proteins (TFT7) might mediate cross-talk between the salt stress and potassium and iron-deficiency signalling pathways in tomato roots.
Xu
Wei Feng
WF
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
Shi
Wei Ming
WM
D048948:14-3-3 Proteins / Q000235:genetics*; D001483:Base Sequence; D017931:DNA Primers; D020869:Gene Expression Profiling; D007501:Iron / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D018517:Plant Roots / Q000378:metabolism; D011188:Potassium / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012965:Sodium Chloride / Q000378:metabolism*
D048948:14-3-3 Proteins; D017931:DNA Primers; D012965:Sodium Chloride; D007501:Iron; D011188:Potassium