Compounds Interacting with the Ethylene Receptor in Plants

Abstract

Some of the compounds binding to the ethylene receptor induce an ethylene response, but others prevent it. The compounds preventing an ethylene response have been developed into a means for protecting plants against ethylene and extending the life of some plant material. 1‐Methylcyclopropene (1‐MCP), a compound now commercially available under the names EthylBloc and SmartFresh™, is currently being used on flowers, fruit and vegetables with great success. In ethylene sensitive flowers, among other responses, it prevents senescence and abscission of plant organs; in fruit and vegetables it slows down the ripening process. Other similar compounds are now being developed for a range of methods of application.

Ethylene Interacts with Abscisic Acid to Regulate Endosperm Rupture during Germination: A Comparative Approach UsingLepidium sativumandArabidopsis thaliana

“…For example, hole formation was promoted when the isolated caps were treated with GA (10 mM GA 4+7 60.0 6 9.4% compared with CON 26.9 6 8.8% cap holes on day 3) or with 1-aminocyclopropane-1-carboxylic acid (ACC), the direct precursor of ethylene (Figure 2). In keeping with this, treatment with NBD, a well-characterized ethylene action inhibitor that binds to the ethylene receptors (Sisler and Serek, 2003), inhibited cap hole formation (Figure 2). The reversion of this inhibition by simultaneous treatment with NBD+ACC demonstrates the specificity of this effect for the ethylene action (i.e., ACCderived ethylene displaces the bound NBD).…”

“…Thus, ethylene or ACC counteract the ABA-induced inhibition. In addition, as the ethylene action inhibitor NBD can only be displaced from the receptor binding site by ethylene itself (Sisler and Serek, 2003), this result demonstrates that ACC acts via its conversion to ethylene by ACO and suggests that ethylene signaling is required for the response.…”

“…This is, at least in part, due to a higher ABA content in the etr1 mutant seeds (Chiwocha et al, 2005). The ethylene action inhibitor 2,5-norbornadiene (NBD) binds specifically to ethylene receptors in direct competition with ethylene for the ethylene binding site (Sisler and Serek, 2003). Experiments with this inhibitor in many species, including Arabidopsis (Siriwitayawan et al, 2003), tobacco (Nicotiana tabacum; Leubner-Metzger et al, 1998), pea (Pisum sativum; Petruzzelli et al, 2000), and others (Kucera et al, 2005) show that the influence of ethylene receptors on the regulation of seed germination is a phylogenetically widespread phenomenon.…”

Impact of Different Environmental Stimuli on the Release of 1-MCP from Boron-MCP Complexes

“…However, ethylene also is responsible for the factors that cause defects in product quality or premature death such as loss of cellular turgor and chlorophyll, pigment degradation, irregular opening, yellowing or shedding of flowers and leaves (Serek, Woltering, Sisler, Frello & Sriskandarajah, 2006). 1-Methylcyclopropene (1-MCP), a cyclic olefin used commercially as a synthetic plant growth regulator, is applied onto post-harvest agricultural products such as fruits (including climacteric and non-climacteric), flowers and vegetables to retard their ripening by working as a preservative and thus prolong their shelf-lives (Sisler & Serek, 2003;Blankenship & Dole, 2003). Because of structural similarity to the natural plant hormone, 1-MCP works as a nontoxic antagonist of ethylene, interacting with and then covalently binding to ethylene receptors.…”

“…The affinity of 1-MCP to the ethylene receptors is ten times greater than that of ethylene (Watkins, 2006), which means a low concentration of 1-MCP is sufficient for application to horticultural products. 1-MCP completely blocks the absorption of ethylene and its hormonal action (Serek, Tamari, Sisler & Borochov, 1995;Sisler & Serek, 2003;Blankenship & Dole, 2003) for a certain time ( Figure 1) until all 1-MCP diffuses from the binding sites or new ethylene receptors develop (Bayer, 1976a(Bayer, , 1976b(Bayer, , 1978Veen, 1983). Under environmental stresses, plants tend to produce more ethylene, resulting in premature opening or early ripening (Chow & McCourt, 2006;De Paepe & Van der Straeten, 2005).…”