Transcriptome sequencing of transgenic poplar (Populus × euramericana 'Guariento') expressing multiple resistance genes

Abstract

BackgroundTransgenic poplar (Populus × euramericana 'Guariento') plants harboring five exogenous, stress-related genes exhibit increased tolerance to multiple stresses including drought, salt, waterlogging, and insect feeding, but the complex mechanisms underlying stress tolerance in these plants have not been elucidated. Here, we analyzed the differences in the transcriptomes of the transgenic poplar line D5-20 and the non-transgenic line D5-0 using high-throughput transcriptome sequencing techniques and elucidated the functions of the differentially expressed genes using various functional annotation methods.ResultsWe generated 11.80 Gb of sequencing data containing 63, 430, 901 sequences, with an average length of 200 bp. The processed sequences were mapped to reference genome sequences of Populus trichocarpa. An average of 62.30% and 61.48% sequences could be aligned with the reference genomes for D5-20 and D5-0, respectively. We detected 11,352 (D5-20) and 11,372 expressed genes (D5-0), 7,624 (56.61%; D5-20) and 7,453 (65.54%; D5-0) of which could be functionally annotated. A total of 782 differentially expressed genes in D5-20 were identified compared with D5-0, including 628 up-regulated and 154 down-regulated genes. In addition, 196 genes with putative functions related to stress responses were also annotated. Gene Ontology (GO) analysis revealed that 346 differentially expressed genes are mainly involved in 67 biological functions, such as DNA binding and nucleus. KEGG annotation revealed that 36 genes (21 up-regulated and 15 down-regulated) were enriched in 51 biological pathways, 9 of which are linked to glucose metabolism. KOG functional classification revealed that 475 genes were enriched in 23 types of KOG functions.ConclusionThese results suggest that the transferred exogenous genes altered the expression of stress (biotic and abiotic) response genes, which were distributed in different metabolic pathways and were linked to some extent. Our results provide a theoretic basis for investigating the functional mechanisms of exogenous genes in transgenic plants.

Assessing bacterial communities in the rhizosphere of 8-year-old genetically modified poplar (Populus spp.)

“…The few differences (Fig. 5) might be caused by differential expression of the transferred exogenous stress response genes, which affect different but related metabolic pathways (Zhang et al 2014). Additionally, we documented reduced numbers of Chloroflexi in the soils from rhizospheres of the planted poplars (transgenic poplars and wild-type poplars) compared with the uncultivated soil rhizosphere.…”

Australian endemic pest tephritids: genetic, molecular and microbial tools for improved Sterile Insect Technique

“…Despite the relative ease of obtaining transcriptomes, compared to complete genomes, there are relatively few published transcriptomes for tephritid species from next generation sequencing. Transcriptomes have been reported comparing wild and mass-reared medfly [ 87 ], adults and different developmental stages of B. dorsalis [ 88 , 89 ], pooled life stages of B. oleae [ 90 ] and sexed preblastoderm embryos of B. jarvisi [ 91 ]. Kumaran et al .…”

Transcriptome analysis of the tea oil camellia (Camellia oleifera) reveals candidate drought stress genes

“…These changes also trigger the synthesis of specific biomolecules that cause a series of complex physiological and metamorphic alterations[ 23 – 26 ]. It has been suggested that stress-responsive genes can be more or less classified into two major categories based on their regulator molecules, the functions of their products, or their effector molecules[ 27 – 29 ]. The first group of molecules plays a direct role in abiotic stress tolerance, protect cells against damage, and sustain cell viability.…”