Comprehensive Proteomics Analysis of Laticifer Latex Reveals New Insights into Ethylene Stimulation of Natural Rubber Production

Abstract

Ethylene is a stimulant to increase natural rubber latex. After ethylene application, both fresh yield and dry matter of latex are substantially improved. Moreover, we found that ethylene improves the generation of small rubber particles. However, most genes involved in rubber biosynthesis are inhibited by exogenous ethylene. Therefore, we conducted a proteomics analysis of ethylene-stimulated rubber latex, and identified 287 abundant proteins as well as 143 ethylene responsive latex proteins (ERLPs) with mass spectrometry from the 2-DE and DIGE gels, respectively. In addition, more than 1,600 proteins, including 404 ERLPs, were identified by iTRAQ. Functional classification of ERLPs revealed that enzymes involved in post-translational modification, carbohydrate metabolism, hydrolase activity, and kinase activity were overrepresented. Some enzymes for rubber particle aggregation were inhibited to prolong latex flow, and thus finally improved latex production. Phosphoproteomics analysis identified 59 differential phosphoproteins; notably, specific isoforms of rubber elongation factor and small rubber particle protein that were phosphorylated mainly at serine residues. This post-translational modification and isoform-specific phosphorylation might be important for ethylene-stimulated latex production. These results not only deepen our understanding of the rubber latex proteome but also provide new insights into the use of ethylene to stimulate rubber latex production.

Complementary transcriptome and proteome profiling in the mature seeds of Camellia oleifera from Hainan Island

“…Thirty washed fractions were collected at one-minute intervals and further freeze-dried, then subjected to a High-resolution Mass Spectrometer Triple TOF 6600 system (SCIEX, USA). These peptides were automatically selected, and the corresponding proteins were identified through the ProGroup TM algorithm and ProteinPilot TM software V5.0 (SCIEX, USA) to calculate the error factor (EF), reporter peak area and p value as described by Xuchu Wang et al [33]. A protein database was established using target protein sequences predicted via TransDecoder software based on the transcriptome data.…”

Plant Latex, from Ecological Interests to Bioactive Chemical Resources

“…Arg. (Euphorbiaceae) showed chitinase and glucanase in primary and secondary lutoids to be playing a crucial role in rubber particle aggregation in the plant [115]. Under normal conditions, chitinase does not interact with glucanase.…”

“…Consequently, the membraneembedded hevamine interacts with membrane-localized glucanase facilitating the rubber particle aggregation and subsequent rubber latex coagulation. Finally, latex vessels become plugged with rubber coagulates, which stops the latex flow [46,115]. Apart from the role of proteins on rubber particle aggregation connected to latex coagulation, the effects of other chemical factors such as enzymes and reactive oxygen species have been investigated [116,117].…”

A Multi‐Omics Analysis of Glycine max Leaves Reveals Alteration in Flavonoid and Isoflavonoid Metabolism Upon Ethylene and Abscisic Acid Treatment

“…With regards to the ET/ABA‐induced changes in plants, studies were mainly focused on the fruits, because of their involvement in fruit ripening and senescence . To date, only few studies have been published, that investigated, for example, the effect of ET on other tissue proteomes, like the latex proteome in rubber and the microsomal membrane fraction proteome of Arabidopsis thaliana seedlings . Despite these studies, a global view of changes in the proteome during ET and ABA treatments is still missing, especially in context of the LAPs.…”