Transcriptome analysis of threeAgavefiber-producing cultivars suitable for biochemicals and biofuels production in semiarid regions

Abstract

Agaves, which have been grown commercially for fiber or alcoholic beverages, are emerging as a candidate crop for biochemicals and biofuels production in semiarid regions because of their high productivity in low rainfall areas, drought tolerance, and low lignin content.In this work, we present the transcriptomic atlas of Agave sisalana, Agave fourcroydes, and agave hybrid 11648 (A. amaniensis x A. angustifolia) under prolonged drought in field conditions. Leaf, stem, and root tissues were sequenced, and gene expression profiles were correlated with biomass composition, enzymatic hydrolysis of cell wall carbohydrates, histochemical analysis, and non-structural carbohydrates content.Differences in biomass accessibility were attributed to either lignin content or lignin composition, possibly through modification of s/g ratio promoted by changes in Caffeic Acid 3-O-Methyltransferase (COMT) transcript abundance. Unlike most plants, the most highly expressed transcripts do not encode photosynthetic proteins, but rather involved in stress response. Although the three cultivars presented quantitative differences in global gene expression, they activated a highly overlapping set of genes. The main molecular strategies employed by agave to cope with high-temperature and drought seem to consist in overexpressing HSP and LEA, as well as promoting raffinose accumulation as an osmolyte.In conclusion, our data provide vital new genetic information for the study of Agave species and provide new insights into cell wall architecture, recalcitrance, and resistance to abiotic stresses for these species.

The Sisal Virome: Uncovering the Viral Diversity of Agave Varieties Reveals New and Organ-Specific Viruses

“…In this study, we investigated the sisal virome using transcriptomic datasets previously generated by Raya et al (2020) [ 29 ]. Our samples were extracted from sections of the leaves, stems, and roots from three different seven-year-old adult plants of A. sisalana, A. fourcroydes , and the Agave hybrid 11648 (( A. amaniensis x A. angustifolia ) x A. amaniensis ) collected at the EMBRAPA collection in Monteiro, in the state of Paraíba, Brazil (07°53′ S; 37°07′ W, elevation: 619 m).…”

“…The sequencing was done on the Illumina HiSeq 4000 system, generating 50 bp paired-end reads. More details can be found in Raya et al (2020) [ 29 ]. The DNA Libraries, one for each Agave taxon, were prepared using the KAPA Hyper Prep Kit (07962312001) following the manufacturer’s instructions.…”

“…DNA and RNA followed by digestion with RNases/DNases [ 27 ], and even amplification-based methods [ 28 ]. Among them, the next-generation sequencing of RNA (metatranscriptomics) has been consolidated as an important unbiased strategy for virome studies [ 23 , 29 , 30 ]. Indeed, this strategy allows the detection of almost all viral species, since most of the viruses are made of or produce RNA molecules during replication, which would not be detected using DNA deep sequencing.…”