The relationship between latex metabolism gene expression with rubber yield and related traits in Hevea brasiliensis

Abstract

BackgroundExpression patterns of many laticifer-specific gens are closely correlative with rubber yield of Hevea brasiliensis (para rubber tree). To unveil the mechanisms underlying the rubber yield, transcript levels of nine major latex metabolism-related genes, i.e., HMG-CoA synthase (HMGS), HMG-CoA reductase (HMGR), diphosphomevalonate decarboxylase (PMD), farnesyl diphosphate synthase (FPS), cis-prenyltransferase (CPT), rubber elongation factor (REF), small rubber particle protein (SRPP), dihydroxyacid dehydratase (DHAD) and actin depolymerizing factor (ADF), were dertermined, and the relationship between rubber yield with their expression levels was analysed.ResultsExcept HbHMGR1, HbPMD and HbDHAD, most of these genes were predominantly expressed in latex, and bark tapping markedly elevated the transcript abundance of the analyzed genes, with the 7th tapping producing the greatest expression levels. Both ethephon (ETH) and methyl jasmonate (MeJA) stimulation greatly induced the expression levels of the examined genes, at least at one time point, except HbDHAD, which was unresponsive to MeJA. The genes’ expression levels, as well as the rubber yields and two yield characteristics differed significantly among the different genotypes examined. Additionally, the latex and dry rubber yields increased gradually but the dry rubber content did not. Rubber yields and/or yield characteristics were significantly positively correlated with HbCPT, HbFPS, HbHMGS, HbHMGR1 and HbDHAD expression levels, negatively correlated with that of HbREF, but not significantly correlated with HbPMD, HbSRPP and HbADF expression levels. In addition, during rubber production, significantly positive correlations existed between the expression level of HbPMD and the levels of HbREF and HbHMGR1, between HbSRPP and the levels of HbHMGS and HbHMGR1, and between HbADF and HbFPS.ConclusionsThe up-regulation of these genes might be related to the latex production of rubber trees under the stress of bark tapping and latex metabolism. The various correlations among the genes implied that there are differences in their synergic interactions. Thus, these nine genes might be related to rubber yield and yield-related traits in H. brasiliensis, and this work increases our understanding of their complex functions and how they are expressed in both high-and medium-yield rubber tree varieties and low-yield wild rubber tree germplasm.Electronic supplementary materialThe online version of this article (10.1186/s12864-018-5242-4) contains supplementary material, which is available to authorized users.

Molecular Cloning and Functional Analysis of DXS and FPS Genes from Zanthoxylum bungeanum Maxim

“…For Matricaria recutita L., MrFPS is most highly expressed in flowers and stems [ 43 ]. In H. brasiliensis , HbFPS is not expressed in roots, stems, leaves, and other tissues but is highly expressed in latex [ 44 ]. These studies have shown that the spatiotemporal expression patterns of ZbDXS and ZbFPS genes in different plants are quite different.…”

Molecular markers to devise predictive models for juvenile selection in Hevea rubber

“…Based on the proteins they encode, genes expressed in the latex of Hevea can be categorized into three groups: defence‐related proteins such as hevein (Broekaert et al, 1990), chitinase (Martin, 1991), b‐1,3‐glucanase (Chye & Cheung, 1995) and HEVER (Sivasubramaniam et al, 1995); rubber biosynthesis‐related proteins such as REF (Goyvaerts et al, 1991), hydroxymethylglutaryl‐CoA reductase, farnesyl diphosphate synthase (Adiwilaga & Kush, 1996), HMG‐CoA synthase (HMGS), diphosphomevalonate decarboxylase (PMD), cis ‐prenyltransferase (CPT), small rubber particle protein (SRPP), dihydroxy acid dehydratase (DHAD) and actin‐depolymerizing factor (ADF) (Wu et al, 2018). latex allergens (proteins) like Hev b 3 (Yeang et al, 1996), Hev b 4, Hev b 5 (Akasawa et al, 1996; Slater et al, 1996) and Hev b 7 (Sowka et al, 1998).…”

“…• rubber biosynthesis-related proteins such as REF (Goyvaerts et al, 1991), hydroxymethylglutaryl-CoA reductase, farnesyl diphosphate synthase (Adiwilaga & Kush, 1996), HMG-CoA synthase (HMGS), diphosphomevalonate decarboxylase (PMD), cisprenyltransferase (CPT), small rubber particle protein (SRPP), dihydroxy acid dehydratase (DHAD) and actin-depolymerizing factor (ADF) (Wu et al, 2018).…”

“…However, when we think of utilizing juvenile seedlings, DNA markers are to be those that have strong linkage with genes that express conspicuously. Markers that have linkage with genes of REF, SRPP, acetyl‐CoA acetyltransferase, HMGS, and HMGR are worthy (Wu et al, 2018). Seedlings in which such genes are up‐regulated can make worthwhile selection (Sando et al, 2008).…”

Photosynthesis-Related Responses of Colombian Elite Hevea brasiliensis Genotypes under Different Environmental Variations: Implications for New Germplasm Selection in the Amazon

“…is a deciduous perennial species native to the Amazon rainforest and belongs to the Euphorbiaceae family [1]. Latex is extracted from this crop and is the main source of natural rubber for the tire industry, representing up to 90% of the rubber sold in international markets [2]. In Colombia, there are about 69,000 ha of rubber, with an estimated national production of 7500 tons per year, distributed mainly in the states of Meta, Santander, Antioquia, Vichada and Caquetá [3].…”