Farnesylation of components of the ethylene signaling pathway may be necessary to the development of superficial scald in apples.
Haines M.M., Mattinson D.S., Fellman J.K.
5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.77
2004
บทคัดย่อ
Farnesylation of components of the ethylene signaling pathway may be necessary to the development of superficial scald in apples.
Superficial scald is an apple storage disorder characterized by patches of browned or blackened peel that seriously impact fruit marketability.Current thought relates peel cell death associated with scald to products of farnesene oxidation, most notably oxygen radicals, yet action of the plant hormone ethylene is also strongly implicated in the development of scald.Some components of the ethylene signaling pathway have been identified, two of which are known to physically interact: ETR1, an ethylene receptor, and CTR1, a mitogen activated protein kinase kinase kinase (MAPKKK), and a putative component of a MAPK signaling cascade.Farnesyl protein transferase (FPT), is the enzyme responsible for farnesylating proteins in both plant and animal models.The hydrophobic farnesyl moiety targets the protein to a membrane or hydrophobic farnesyl moiety targets the protein.Recently, FPT has received attention in biomedical studies due to implications regarding its role in cellular signal transduction and the development of several forms of human cancer.Apparently, studies in other systems suggest farnesylated proteins such as Ras are necessary to assist in targeting proteins like MAPKs to cell membranes, and FPT activity is necessary for the activation of all major classes of MAPKs.In an attempt to dissect the molecular events leading to the development of superficial scald, we studied ‘Granny Smith’ scald development by assessing benchmarks for volatile production, and collection of organic radical species by using a chromotropic spin-trapping compound in peel from apples stored in regular and controlled atmospheres, in 1-methylcyclopropene-treated apples, and in apples treated with an FPT inhibitor.We have verified the presence of FPT protein and are studying the potential interaction with CTR1 with regard to attenuation/enhancement of scald symptoms in apple peel tissue.