title: Transcriptome and Metabolite analysis reveal candidate genes of the cardiac glycoside biosynthetic pathway from Calotropis procera.
abstract: Calotropis procera is a medicinal plant of immense importance due to its pharmaceutical active components, especially cardiac glycosides (CG). As genomic resources for this plant are limited, the genes involved in CG biosynthetic pathway remain largely unknown till date. Our study on stage and tissue specific metabolite accumulation showed that CG's were maximally accumulated in stems of 3 month old seedlings. De novo transcriptome sequencing of same was done using high throughput Illumina HiSeq platform generating 44074 unigenes with average mean length of 1785 base pair. Around 66.6% of unigenes were annotated by using various public databases and 5324 unigenes showed significant match in the KEGG database involved in 133 different pathways of plant metabolism. Further KEGG analysis resulted in identification of 336 unigenes involved in cardenolide biosynthesis. Tissue specific expression analysis of 30 putative transcripts involved in terpenoid, steroid and cardenolide pathways showed a positive correlation between metabolite and transcript accumulation. Wound stress elevated CG levels as well the levels of the putative transcripts involved in its biosynthetic pathways. This result further validated the involvement of identified transcripts in CGs biosynthesis. The identified transcripts will lay a substantial foundation for further research on metabolic engineering and regulation of cardiac glycosides biosynthesis pathway genes.
authors.affiliation: Botany division, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Akansha
authors.initials: A
authors.lastname: Pandey
authors.affiliation: Botany division, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Vishakha
authors.initials: V
authors.lastname: Swarnkar
authors.affiliation: Botany division, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Tushar
authors.initials: T
authors.lastname: Pandey
authors.affiliation: Botany division, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Piush
authors.initials: P
authors.lastname: Srivastava
authors.affiliation: Sophisticated Analytical Instrument Facility, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Kanojiya
authors.affiliation: Botany division, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Dipak Kumar
authors.initials: DK
authors.lastname: Mishra
authors.affiliation: Botany division, CSIR-CDRI, Sector 10, Jankipuram Extension, Sitapur Road, Lucknow 226031, Uttar Pradesh, India.
authors.forename: Vineeta
authors.initials: V
authors.lastname: Tripathi
mesh_terms: D031107:Calotropis / Q000235:genetics / Q000378:metabolism; D002301:Cardiac Glycosides / Q000096:biosynthesis / Q000235:genetics; D017343:Genes, Plant; D055442:Metabolome / Q000502:physiology*; D059467:Transcriptome / Q000502:physiology*
chemical_list: D002301:Cardiac Glycosides