Molecular characterization of a miraculin-like gene differentially expressed during coffee development and coffee leaf miner infestation

Abstract

The characterization of a coffee gene encoding a protein similar to miraculin-like proteins, which are members of the plant Kunitz serine trypsin inhibitor (STI) family of proteinase inhibitors (PIs), is described. PIs are important proteins in plant defence against insects and in the regulation of proteolysis during plant development. This gene has high identity with the Richadella dulcifica taste-modifying protein miraculin and with the tomato protein LeMir; and was named as CoMir (Coffea miraculin). Structural protein modelling indicated that CoMir had structural similarities with the Kunitz STI proteins, but suggested specific folding structures. CoMir was up-regulated after coffee leaf miner (Leucoptera coffella) oviposition in resistant plants of a progeny derived from crosses between C. racemosa (resistant) and C. arabica (susceptible). Interestingly, this gene was down-regulated during coffee leaf miner herbivory in susceptible plants. CoMir expression was up-regulated after abscisic acid application and wounding stress and was prominent during the early stages of flower and fruit development. In situ hybridization revealed that CoMir transcripts accumulated in the anther tissues that display programmed cell death (tapetum, endothecium and stomium) and in the metaxylem vessels of the petals, stigma and leaves. In addition, the recombinant protein CoMir shows inhibitory activity against trypsin. According to the present results CoMir may act in proteolytic regulation during coffee development and in the defence against L. coffeella. The similarity of CoMir with other Kunitz STI proteins and the role of CoMir in plant development and plant stress are discussed.

Proteomics analysis reveals novel host molecular mechanisms associated with thermotherapy of ‘Ca. Liberibacter asiaticus’-infected citrus plants

“…Although characteristically expressed in fruits, the induction of miraculin-like proteins in non-fruit tissues (i.e. stems, leaves or roots) has been strongly associated with pest or pathogen attack, suggesting their involvement in defense [42, 53, 54]. Tsukuda et al [41] first characterized two distinct miraculin-like proteins in rough lemon ( Citrus jambhiri Lush), RlemMLP1 (miraculin-like protein 1) and RlemMLP2 (miraculin-like protein 2) and demonstrated the induction of RlemMLP1 and/or RlemMLP2 by microbe attack.…”

Transcriptional analysis of late ripening stages of grapevine berry

“…In Citrus and Poncirus trifoliata , a miraculin homologue is down-regulated by cold stress (which reduces water availability) [53]. In coffee, Coffea miraculin ( CoMir ) expression was prominent during the early stages of fruit development and then repressed throughout fruit maturation [54]. Like the up-regulation of VvGolS (see above), the down-regulation of the grapevine miraculin-like gene may be a response to a decrease of water availability.…”

Sequences and transcriptional analysis ofCoffea arabicavar. Caturra andCoffea libericaplant responses to coffee berry borerHypothenemus hampei(Coleoptera: Curculionidae: Scolytinae) attack

“…However, this gene was also upregulated in C. arabica. The trypsin inhibitor Kunitz gene is already reported in coffee by Mondego et al (2005Mondego et al ( , 2011; this is the same miraculin-like gene, CoMir. Structural protein modeling indicated that CoMir had structural similarities with the Kunitz STI proteins but suggested specific folding structures (Mondego et al 2011).…”

“…The trypsin inhibitor Kunitz gene is already reported in coffee by Mondego et al (2005Mondego et al ( , 2011; this is the same miraculin-like gene, CoMir. Structural protein modeling indicated that CoMir had structural similarities with the Kunitz STI proteins but suggested specific folding structures (Mondego et al 2011). The gene is also upregulated after coffee leaf miner (Leucoptera coffella) oviposition in resistant plants of a progeny derived from crosses between C. racemosa (resistant) and C. arabica (susceptible) and downregulated during coffee leaf miner oviposition and larvae eclosion (herbivoria) in susceptible plants.…”

“…genes related to the jasmonic acid pathway), such as a hevein-like protein (Reymond et al 2000), isoprene synthetase (Loivama¨ki et al 2008), a trypsin inhibitor Kunitz gene (Mondego et al 2005(Mondego et al , 2011, an S-adenosyl-l-methionine:salicylic acid carboxyl methyltransferase (Ko¨llner et al 2010) and patatinlike protein (Alidhai and Rydel 2010) that has been reported as specifically induced by insects. These genes induced or upregulated by insects that show overexpression in C. liberica, the genotype with lower susceptibility to CBB attack when compared to C. arabica var.…”