Dataset of transcriptome assembly of date palm embryogenic calli and functional annotation.

Date palm (Phoenix dactylifera L.; 2n = 36; Arecaceae), cultivated in tropical and sub-tropical regions worldwide, is a staple food for people in the Middle East region and has economic value throughout the world. Tissue culture is considered as a feasible technique for the large-scale multiplication of elite date palm varieties. In this article, we report the transcriptome assembly from the embryogenic calli of Khalas variety of date palm. A total of 50,852,331 paired-end (PE) raw reads were acquired using an Illumina sequencing platform. Reference-based assembly, with date palm genome, resulted in 53251 transcripts. A total of 63888 Gene Ontology (GO) terms could be annotated from the assembled transcriptome. Also, transcription factor families and small RNAs were annotated from the assembled transcriptome. Results of the pathway analysis revealed that a total of 2584 transcripts were involved in various metabolic pathways. Transcripts with possible roles in somatic embryogenesis were also identified. The dataset provides insights into the expression pattern of various genes during early somatic embryogenesis in date palm.

De novo assembly and characterization of global transcriptome of coconut palm (Cocos nucifera L.) embryogenic calli using Illumina paired-end sequencing.

Production and supply of quality planting material is significant to coconut cultivation but is one of the major constraints in coconut productivity. Rapid multiplication of coconut through in vitro techniques, therefore, is of paramount importance. Although somatic embryogenesis in coconut is a promising technique that will allow for the mass production of high quality palms, coconut is highly recalcitrant to in vitro culture. In order to overcome the bottlenecks in coconut somatic embryogenesis and to develop a repeatable protocol, it is imperative to understand, identify, and characterize molecular events involved in coconut somatic embryogenesis pathway. Transcriptome analysis (RNA-Seq) of coconut embryogenic calli, derived from plumular explants of West Coast Tall cultivar, was undertaken on an Illumina HiSeq 2000 platform. After de novo transcriptome assembly and functional annotation, we have obtained 40,367 transcripts which showed significant BLASTx matches with similarity greater than 40 % and E value of ≤10(-5). Fourteen genes known to be involved in somatic embryogenesis were identified. Quantitative real-time PCR (qRT-PCR) analyses of these 14 genes were carried in six developmental stages. The result showed that CLV was upregulated in the initial stage of callogenesis. Transcripts GLP, GST, PKL, WUS, and WRKY were expressed more in somatic embryo stage. The expression of SERK, MAPK, AP2, SAUR, ECP, AGP, LEA, and ANT were higher in the embryogenic callus stage compared to initial culture and somatic embryo stages. This study provides the first insights into the gene expression patterns during somatic embryogenesis in coconut.