Genome-wide identification and expression analysis of the ADH gene family under diverse stresses in tobacco (Nicotiana tabacum L.)

Abstract

Background Alcohol dehydrogenases (ADHs) are the crucial enzymes that can convert ethanol into acetaldehyde. In tobacco, members of ADH gene family are involved in various stresses tolerance reactions, lipid metabolism and pathways related to plant development. It will be of great application significance to analyze the ADH gene family and expression profile under various stresses in tobacco. Results A total of 53 ADH genes were identified in tobacco (Nicotiana tabacum L.) genome and were grouped into 6 subfamilies based on phylogenetic analysis. Gene structure (exon/intron) and protein motifs were highly conserved among the NtADH genes, especially the members within the same subfamily. A total of 5 gene pairs of tandem duplication, and 3 gene pairs of segmental duplication were identified based on the analysis of gene duplication events. Cis-regulatory elements of the NtADH promoters participated in cell development, plant hormones, environmental stress, and light responsiveness. The analysis of expression profile showed that NtADH genes were widely expressed in topping stress and leaf senescence. However, the expression patterns of different members appeared to be diverse. The qRT-PCR analysis of 13 NtADH genes displayed their differential expression pattern in response to the bacterial pathogen Ralstonia solanacearum L. infection. Metabolomics analysis revealed that NtADH genes were primarily associated with carbohydrate metabolism, and moreover, four NtADH genes (NtADH20/24/48/51) were notably involved in the pathway of alpha-linolenic acid metabolism which related to the up-regulation of 9-hydroxy-12-oxo-10(E), 15(Z)-octadecadienoic acid and 9-hydroxy-12-oxo-15(Z)-octadecenoic acid. Conclusion The genome-wide identification, evolutionary analysis, expression profiling, and exploration of related metabolites and metabolic pathways associated with NtADH genes have yielded valuable insights into the roles of these genes in response to various stresses. Our results could provide a basis for functional analysis of NtADH gene family under stressful conditions.

Functional and evolutionary comparative analysis of the DIR gene family in Nicotiana tabacum L. and Solanum tuberosum L.

“…Mechanisms such as polyploidization and region-specific gene duplication, including tandem repeats and segmental repeats, have been considered as important mechanisms for the expansion of plant gene families [ 29 , 30 ]. This study revealed the presence of homologous gene clusters and collinear gene pairs identified in both tobacco (1 homologous gene cluster and 6 collinear gene pairs) and potato (4 homologous gene clusters and 7 collinear gene pairs), indicating that replication events were the main source of DIR gene family expansion in these species [ 29 , 31 ]. It is worth noting that the incomplete genomic assembly of tobacco, with nearly half of the NtDIR genes located on scaffolds, might reduce the frequency of replication events compared to potato.…”

“…A total of 75 tobacco seedlings were carefully selected and then inoculated with a highly virulent pathogenic strain of Ras that had been isolated by our laboratory [ 48 ]. Inoculation was performed by mechanically wounding the roots and followed by irrigation with 30 mL of Ras liquid with a concentration of 10 8 cfu/mL [ 31 ]. These plants were then cultivated in a high-temperature and high-humidity greenhouse (30℃, about 80% humidity, 12 h/d light).…”