The Nicotiana sylvestris nucleobase cation symporter 1 retains a dicot solute specificity profile

It has been shown that Atropa belladonna acts as a symptomless carrier of Hyosoyamus Virus I. Some symptoms caused by this virus on other solanaceous plants are described.A naturally occurring virus complex in Hyoscyamus niger was found to consist of Solanum Virus I (potato virus X) and Brassica Virus I. During the course of the investigation it was found that potato virus X forms local lesions on the cotyledons of ridge cucumber without systemic infection and that Brassica Virus I behaves similarly on the inoculated leaves of Nicotiana sylvestris.

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Carotenoid Cleavage Dioxygenases: Identification, Expression, and Evolutionary Analysis of This Gene Family in Tobacco

International Journal of Molecular Sciences ◽

10.3390/ijms20225796 ◽

2019 ◽

Vol 20 (22) ◽

pp. 5796

Author(s):

Qianqian Zhou ◽

Qingchang Li ◽

Peng Li ◽

Songtao Zhang ◽

Che Liu ◽

...

Keyword(s):

Gene Family ◽

Physiological Stress ◽

Expression Patterns ◽

Functional Characterization ◽

Hormone Treatment ◽

Nicotiana Sylvestris ◽

Regulatory Elements ◽

Evolutionary Analysis ◽

Comprehensive Overview ◽

Carotenoid Cleavage Dioxygenases

Carotenoid cleavage dioxygenases (CCDs) selectively catalyze carotenoids, forming smaller apocarotenoids that are essential for the synthesis of apocarotenoid flavor, aroma volatiles, and phytohormone ABA/SLs, as well as responses to abiotic stresses. Here, 19, 11, and 10 CCD genes were identified in Nicotiana tabacum, Nicotiana tomentosiformis, and Nicotiana sylvestris, respectively. For this family, we systematically analyzed phylogeny, gene structure, conserved motifs, gene duplications, cis-elements, subcellular and chromosomal localization, miRNA-target sites, expression patterns with different treatments, and molecular evolution. CCD genes were classified into two subfamilies and nine groups. Gene structures, motifs, and tertiary structures showed similarities within the same groups. Subcellular localization analysis predicted that CCD family genes are cytoplasmic and plastid-localized, which was confirmed experimentally. Evolutionary analysis showed that purifying selection dominated the evolution of these genes. Meanwhile, seven positive sites were identified on the ancestor branch of the tobacco CCD subfamily. Cis-regulatory elements of the CCD promoters were mainly involved in light-responsiveness, hormone treatment, and physiological stress. Different CCD family genes were predominantly expressed separately in roots, flowers, seeds, and leaves and exhibited divergent expression patterns with different hormones (ABA, MeJA, IAA, SA) and abiotic (drought, cold, heat) stresses. This study provides a comprehensive overview of the NtCCD gene family and a foundation for future functional characterization of individual genes.

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Analysis of wound-induced gene expression in Nicotiana species with contrasting alkaloid profiles

Functional Plant Biology ◽

10.1071/fp03242 ◽

2004 ◽

Vol 31 (7) ◽

pp. 721 ◽

Cited By ~ 23

Author(s):

Steven J. Sinclair ◽

Richard Johnson ◽

John D. Hamill

Keyword(s):

Fold Increase ◽

Transcript Abundance ◽

Nicotiana Sylvestris ◽

Nicotiana Glauca ◽

Transcriptional Responses ◽

Transcript Levels ◽

Solanaceae Species ◽

Genes Encoding ◽

Root Tissues ◽

Alkaloid Profiles

We determined the capacity of three Nicotiana (Solanaceae) species with very different alkaloid profiles (Nicotiana sylvestris Speg & Comes, Nicotiana alata Link & Otto and Nicotiana glauca Grah.) to increase their alkaloid contents in both leaf and root tissues following foliage damage. We also investigated the transcriptional responses of genes encoding enzymes important for alkaloid biosynthesis, namely quinolinate phosphoribosyltransferase (QPT), putrescine N-methyltransferase (PMT), ornithine decarboxylase (ODC) and the putative alkaloid biosynthetic gene A622. In response to wounding of foliage in the well studied ‘model’ species N. sylvestris, a rise, approximately 2-fold, in leaf nicotine levels was observed several days after a 4–5-fold increase in the transcript levels of all genes in the roots. In contrast, leaf tissues of the ornamental tobacco N. alata showed very low levels of any pyridine alkaloid, even when analysed 1 week after wounding, correlating with a general lack of transcript abundance representing any of these genes in leaves or roots following foliage damage. However, addition of methyl jasmonate to cultured roots of N. alata did produce elevated levels of nicotine and anatabine raising the possibility that components of the leaf–root wound signalling system in N. alata are different from those in N. sylvestris. Wounding of the tree tobacco N. glauca, was followed by a 2-fold increase in anabasine levels several days later. This increase followed a large rise in transcript levels of ODC, QPT and A622, though not PMT, in wounded leaves, but not in non-wounded leaves or roots. These data support the hypothesis that N. glauca is able to produce increased anabasine levels following wounding in its foliage, setting it apart from N. sylvestris where induced alkaloid production takes place in roots. We discuss the possibility that increased transcript levels detected by ODC and A622 probes play important roles in anabasine synthesis in N. glauca.

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