Transcriptome analysis provides insight into prickle development and its link to defense and secondary metabolism in Solanum viarum Dunal

Abstract

Prickles are epidermal outgrowth found on the aerial surface of several terrestrial plants. Microscopic studies on prickles of S. viarum Dunal indicated a crucial role of glandular trichomes (GTs) in their development. A spontaneously obtained prickleless mutant showed normal epidermal GTs, but its downstream developmental process to prickle was perturbed. Thus, prickleless mutant offers an ideal opportunity to unveil molecular regulators working downstream to GTs in the prickle formation. Differential transcriptome analysis of epidermis of prickly and prickleless mutant revealed that expression of several defense regulators like ethylene, salicylic acid, PR-proteins, etc. were significantly down-regulated in prickleless mutant, provide an important link between defense and prickle development. It was also noteworthy that the expression of few essential development related TFs like MADS-box, R2R3-MYB, REM, DRL1, were also down-regulated in the stem, petioles, and leaves of prickleless mutant indicating their potential role in prickle development. Interestingly, the gene expression of terpenoid, steroid, flavonoid, glucosinolate, and lignin biosynthesis pathways were up-regulated in prickleless mutant. The biochemical and qRT-PCR analysis also confirmed metabolite elevation. These results indicated that the loss of prickle was compensated by elevated secondary metabolism in the prickleless mutant which played important role in the biotic and abiotic stress management.

Genetic determinism of prickles in rose

“…We identified two different types of prickles in our population: it appears that GP and NGP originate from glandular and non-glandular structures, respectively. This conclusion is different from previous studies in rose, which reported that prickles were extensions or modifications of glandular trichomes (Kellogg et al 2011), and in other species (Ma et al 2016b;Pandey et al 2018). Asano et al (2008) observed two types of prickles in the cultivated rose 'Laura', described as large size and small size prickles.…”

Comparative Transcriptome Analysis Reveals Key Genes and Pathways Involved in Prickle Development in Eggplant

“…Previous studies on raspberry and blackberry prickles have shown that they are outgrowths of epidermal tissue generated from modified glandular trichomes (GTs); once the outermost cells become lignified, lignification continues inward and downwards until the prickles become completely lignified and thus mature [8,9]. A phenotypic analysis of the prickles in Solanum viarum Dunal revealed that they may initiate from GTs or be induced by some signals derived from GTs [10]. Transcriptome analyses in raspberry and S. viarum further identified several transcription factors (TFs) that may play important roles in prickle development [10,11].…”

“…A phenotypic analysis of the prickles in Solanum viarum Dunal revealed that they may initiate from GTs or be induced by some signals derived from GTs [10]. Transcriptome analyses in raspberry and S. viarum further identified several transcription factors (TFs) that may play important roles in prickle development [10,11]. In eggplant, several quantitative trait loci (QTLs) for prickle have been identified on chromosomes 2, 6, 7 and 8 [3,[12][13][14].…”

The Dynamic Genetic-Hormonal Regulatory Network Controlling the Trichome Development in Leaves

“…In this contest, it is interesting that GTL1 coordinates different genetic elements implicated in various aspects of SA metabolism [147]. Recent data, collected by a differential transcriptomic analysis of epidermis of both prickly and prickleless mutants of Solanum viarum (an important medicinal plant), show that the activity of several defense regulators, such as ethylene, SA, and PATHOGEN RELATED-proteins, is significantly repressed in prickleless mutants [148].…”