Transcriptional and post-transcriptional regulation of the jasmonate signalling pathway in response to abiotic and harvesting stress in Hevea brasiliensis

Abstract

BackgroundLatex harvesting in Hevea brasiliensis amounts to strong abiotic stress that can cause a halt in production in the most susceptible clones. Although the role of jasmonic acid has been suggested in laticifer differentiation, its role in latex production and in the response to harvesting stress has received very little attention. Only a few key genes acting in the COI-JAZ-MYC module have been isolated and studied at transcriptional level.ResultsUse of a reference transcriptome obtained on rubber clone PB 260 covering a large number of tissues under different environmental conditions enabled us to identify 24 contigs implicated in the jasmonate signalling pathway in the rubber tree. An analysis of their expression profile by qPCR, combined with hierarchical clustering, suggested that the jasmonate signalling pathway is highly activated in laticifer cells and, more particularly, in the response to harvesting stress. By comparison with their genomic sequences, the existence of regulation by alternative splicing was discovered for JAZ transcripts in response to harvesting stress. Lastly, positive transcriptional regulation of the HbJAZ_1405 gene by MYC was demonstrated.ConclusionThis study led to the identification of all actors of jasmonate signalling pathway and revealed a specific gene expression pattern in latex cells. In-depth analysis of this regulation showed alternative splicing that has been previously shown in Arabidopsis. Interestingly, genotypic variation was observed in Hevea clones with contrasting latex metabolism. This result suggests an involvement of jasmonate signalling pathway in latex production. The data suggest that specific variability of the JA pathway may have some major consequences for resistance to stress. The data support the hypothesis that a better understanding of transcriptional regulations of jasmonate pathway during harvesting stress, along with the use of genotypic diversity in response to such stress, can be used to improve resistance to stress and rubber production in Hevea.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-014-0341-0) contains supplementary material, which is available to authorized users.

LOL2 and LOL5 loci control latex production by laticifer cells in Euphorbia lathyris

“…LOX2 and AOS ), and (3) its 100‐fold increase in the basal accumulation of JA‐Ile, lead us to conclude that LOL2 is critical in the control of JA biosynthesis in the plant. The positive effect of JA on latex production in H. brasiliensis (Hao & Wu, ; Laosombut et al ., ) and the effect that latex harvesting procedures have on genes of the JA pathway and responsive genes were previously reported (Pirrello et al ., ; Laosombut et al ., ). Also, the metabolic pathways that originate from squalene, a common precursor for the synthesis of triterpenes, saponins, and sterols on different plant species, has been reported to be affected by the action of JA (Suzuki et al ., ; Mangas et al ., ; James et al ., ).…”

Transcriptome Analysis of the Signalling Networks in Coronatine-Induced Secondary Laticifer Differentiation from Vascular Cambia in Rubber Trees

“…These JAZ members mediated JA response204348. Although several JAZ homologues were isolated from the latex of rubber trees495051, little is known about their roles in secondary laticifer differentiation. In the present study, 5 of the 13 qRT-PCR validated JAZ homologous unigenes have complete open reading frame (ORF) with ZIM and Jas domains whereas the others’ ORF were incomplete (NCBI’ GEO accession numbers: GSE80596).…”

Comparative transcriptome analysis of latex from rubber tree clone CATAS8-79 and PR107 reveals new cues for the regulation of latex regeneration and duration of latex flow

“…Jasmonate signaling plays a pivotal role in activating the secondary laticifer differentiation and activating the biosynthesis of secondary metabolites [ 42 - 45 ]. Although several members of COI1-JAZ-MCY module have been characterized in rubber tree and JA signaling is suggested to have an important role in regulating rubber biosynthesis in laticifer cells [ 46 - 48 ], the difference in the level of endogenous JAs in laticifer cells among Hevea germplasm remains largely unknown. The present study suggests that the level of endogenous JAs may be higher in the laticifer cells of CATAS 8-79 than that in the laticifer cells of PR107, considering that the expression of unigenes encoding enzymes such as LOX, OPDR, JMT is significantly up-regulated in CATAS8-79.…”