Abstract
Chia (Salvia hispanica L.), a member of the mint family (Lamiaceae), is a rediscovered crop with great importance in health and nutrition and is also the highest known terrestrial plant source of heart-healthy omega-3 fatty acid, alpha linolenic acid (ALA). At present, there is no public genomic information or database available for this crop, hindering research on its genetic improvement through genomics-assisted breeding programs. The first comprehensive analysis of the global transcriptome profile of developing Salvia hispanica L. seeds, with special reference to lipid biosynthesis is presented in this study. RNA from five different stages of seed development was extracted and sequenced separately using the Illumina GAIIx platform. De novo assembly of processed reads in the pooled transcriptome using Trinity yielded 76,014 transcripts. The total transcript length was 66,944,462 bases (66.9 Mb), with an average length of approximately 880 bases. In the molecular functions category of Gene Ontology (GO) terms, ATP binding and nucleotide binding were found to be the most abundant and in the biological processes category, the metabolic process and the regulation of transcription-DNA-dependent and oxidation-reduction process were abundant. From the EuKaryotic Orthologous Groups of proteins (KOG) classification, the major category was “Metabolism” (31.97%), of which the most prominent class was ‘carbohydrate metabolism and transport’ (5.81% of total KOG classifications) followed by ‘secondary metabolite biosynthesis transport and catabolism’ (5.34%) and ‘lipid metabolism’ (4.57%). A majority of the candidate genes involved in lipid biosynthesis and oil accumulation were identified. Furthermore, 5596 simple sequence repeats (SSRs) were identified. The transcriptome data was further validated through confirmative PCR and qRT-PCR for select lipid genes. Our study provides insight into the complex transcriptome and will contribute to further genome-wide research and understanding of chia. The identified novel UniGenes will facilitate gene discovery and creation of genomic resource for this crop.
Highlights
A low ratio of ω-6/ω-3 fatty acids (5 or lower) in the diet is considered healthy for combating cardiovascular diseases, cancer, inflammation and autoimmune diseases
Chia oil has a ω-6/ω-3 fatty acid ratio of
Chia, being an oil seed plant, we identified the transcripts related to TAG biosynthesis that have simple sequence repeats (SSRs), most of which were highly expressed throughout the various developmental stages (S6 Table)
Summary
A low ratio of ω-6/ω-3 fatty acids (5 or lower) in the diet is considered healthy for combating cardiovascular diseases, cancer, inflammation and autoimmune diseases. This ratio averages 16.74 in the US, 15 in the UK and northern Europe and, alarmingly, as high as 38–50 in urban India [1]. The seeds contain approximately 26–35% oil by weight and have the highest known content of the omega-3 fatty acid, α-linolenic acid (approximately 60% of the total fatty acids) [3]. With very high omega-3 fatty acid (α-linolenic acid/ ALA) content, represents an excellent alternative source of this nutritive compound. Chia seeds are a rich source of protein (up to 26%) [3]; total dietary fiber (up to 40%) [5]; antioxidants; essential minerals such as calcium, magnesium, phosphorus, iron, zinc and copper; and vitamins such as thiamine, niacin, riboflavin, vitamin C and vitamin E [6,7], which potentially supports their reputation as a ‘superfood.’
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
