Do Cupins Have a Function Beyond Being Seed Storage Proteins?

Abstract

Plants continue to flourish around the site of the Chernobyl Nuclear Power Plant disaster. The ability of plants to transcend the radio-contaminated environment was not anticipated and is not well understood. The aim of this study was to evaluate the proteome of flax (Linum usitatissimum L.) during seed filling by plants grown for a third generation near Chernobyl. For this purpose, seeds were harvested at 2, 4, and 6 weeks after flowering and at maturity, from plants grown in either non-radioactive or radio-contaminated experimental fields. Total proteins were extracted and the two-dimensional gel electrophoresis (2-DE) patterns analyzed. This approach established paired abundance profiles for 130 2-DE spots, e.g., profiles for the same spot across seed filling in non-radioactive and radio-contaminated experimental fields. Based on Analysis of Variance (ANOVA) followed by sequential Bonferroni correction, eight of the paired abundance profiles were discordant. Results from tandem mass spectrometry show that four 2-DE spots are discordant because they contain fragments of the cupin superfamily-proteins. Most of the fragments were derived from the N-terminal half of native cupins. Revisiting previously published data, it was found that cupin-fragments were also involved with discordance in paired abundance profiles of second generation flax seeds. Based on these observations we present an updated working model for the growth and reproductive success of flax in a radio-contaminated Chernobyl environment. This model suggests that the increased abundance of cupin fragments or isoforms and monomers contributes to the successful growth and reproduction of flax in a radio-contaminated environment.

MSD1 regulates pedicellate spikelet fertility in sorghum through the jasmonic acid pathway

“…8 ). Consistent with the arrest of PS in WT, the top 10 most upregulated genes in the PS of msd1-1 vs WT PS at stage 4 are members of the late embryogenesis abundant protein 44 , 45 and cupin families 46 , indicating that embryo development in WT PS essentially ceases (Supplementary Table 4 and Supplementary Fig. 8 ).…”

A Cell Wall Proteome and Targeted Cell Wall Analyses Provide Novel Information on Hemicellulose Metabolism in Flax

“…Another well-represented group included aspartyl proteases that are also involved in the regulation of PCD during development and stress (71). Other proteins previously associated with stress responses in plants and present in the flax abiotic stress block included cupins, GLPs and osmotin (18,72,73). The defense (biotic stress) class of cell wall proteins is also well represented in whole stems (more so in outer tissues compared with inner tissues) and seeds, but less so in leaves and roots.…”

Dissecting the Seed Maturation and Germination Processes in the Non-Orthodox Quercus ilex Species Based on Protein Signatures as Revealed by 2-DE Coupled to MALDI-TOF/TOF Proteomics Strategy

“…The exception was observed for a couple of members of the cupin family in cotyledons that showed a clear peak at germination stages. This observation is in the direction of proposing alternative roles for this family of proteins [33].…”