Isolation of ESTs from cacao (Theobroma cacao L.) leaves treated with inducers of the defense response

Abstract

Pathogenic diseases represent a major constraint to the growth and yield of cacao (Theobroma cacao L.). Ongoing research on model plant systems has revealed that defense responses are activated via signaling pathways mediated by endogenous signaling molecules such as salicylic acid, jasmonic acid and ethylene. Activation of plant defenses is associated with changes in the expression of large numbers of genes. To gain a better understanding of defense responses in cacao, we have employed suppressive subtractive hybridization (SSH) cDNA libraries, macroarray hybridization analysis, high throughput DNA sequencing and bioinformatics to identify cacao genes induced by these signaling molecules. Additionally, we investigated gene activation by a phytotoxic elicitor-like protein, Nep1. We have identified a unigene set of 1,256 members, including 330 members representing genes induced during the defense response.

Single nucleotide polymorphisms from Theobroma cacao expressed sequence tags associated with witches’ broom disease in cacao

“…On the other hand, the method of sequence alignment is dependent on the availability of sequences in the database and does not identify mistakes due to sequencing. However, in our case, those difficulties were eliminated by the existence of a cacao library of sequencing data obtained in several previous studies (Jones et al, 2002;Gesteira et al, 2007;Verica et al, 2004) and current work carried out by the CEPLAC re-search group, and by the adopted strategy of re-sequencing the selected gene for SNPs identification. After trimming, sequence analysis and alignment, processed with the program CLOURE D, only 44 (28.75%) sequences showed potential for SNP identification.…”

“…Potential sequencing errors were eliminated by comparing the several runs and electropherograms obtained for each individual gene. Jones et al, 2002;Verica et al, 2004) by BLASTX and TBLASTX, adopting an expected value ≤1.10 -4 as being significant. TSH1188 sequences showing similarity and having a size larger than 170 bp were used as reference sequences in the alignment process with similar sequences from the other cDNA libraries using the CLUSTAL W program (http://align.genome.jp/; Thompson et al, 1994).…”

Differentially expressed stress-related genes in the compatible citrus-Citrus leprosis virus interaction

“…One of the major roles of the isoflavones is to provide the disease resistance response by inducing the formation of the defense compounds against phytopathogenic microorganisms. The enzyme IFR catalyzes a NADPH-dependent reduction and acts in the biosynthesis of important and related phenylpropanoid-derived plant defense proteins (Dixon and Steele, 1999;Verica et al, 2004). Lignins are extremely resistant to microbial degradation and are often induced at sites of pathogen infection, playing important roles in cell wall reinforcement and, consequently, increased defense response against infection (Lange et al, 1995;Kawasaki et al, 2006).…”

Construction and Analysis of SSH-cDNA Library from Leaves of Susceptible Rubber Clone Resistant to Powdery Mildew Induced by BTH

“…The mechanism of BTH induced resistance is activation of the plant defense genes and expression resistance-related proteins or enzymes [10]. The defense-related genes of BTH induced diseases resistance to rice, wheat [11], cucumber [12], papaya [13], coffee [14], cocoa [15] and so on were identified and analysed. In rubber tree susceptible clone against the diseases, the peroxidase, phenylalanine aminolyase and β-1,3 glucanase are increasing significantly in leaves after BTH treatment [4,5].…”