Transcriptome Analysis Revealed a Wide Spectrum of Salt Stress Responsive Genes from Atriplex halimus

The saltbush Atriplex halimus is a well adapted plant to dry saline habitats and widely distributed in the Arabian deserts. To identify salt stress responsive genes form A. halimus, total RNA was isolated using RNeasy Midi Kit (Qiagen). Pooled tissue samples (roots, stems, leaves, germinated seeds) were collected from healthy and stressed plants exposed to 200 mM NaCl for 6, 15, or 39 h. The cDNA was prepared and amplified by using SMARTer cDNA Synthesis kit (Clontech). cDNA was sheared via nebulization into small fragments and sequenced in a single 454 run using GS-FLX sequencer (454 Life Sciences). The reads were assembled using CLC Genomics Workbench 4 into more than 37000 EST contigs. More than 23000 generated ESTs could be annotated using Blast2Go. The remaining are either unique or misassembled contigs. Several salt stress responsive genes were detected in the assembly, e.g. CMO, BADH, NAC, NAM, SOS, EREBP, bZip, AP2, LEA-like, MYB, DREB, JERF, MARK, HKT, LCT, NHX, CAX, dehydrin, SNF1, etc…). The tblastn search with NCBI database confirmed the primary annotation.