EST libraries

Efforts to elucidate the genetic basis of biosynthetic pathways tend to result in the identification of structural genes, i.e. genes encoding enzymes that catalyze the conversion of intermediates in a specific pathway. This is in part due to the relatively high expression of the structural genes, which results in abundant representation in expressed sequence tag (EST) libraries, or high probability of identification when cDNA subtraction methods or other methods that rely on differential expression are used. 

Selected siRNA sequences should be aligned against Expressed Sequence Tag (EST) libraries to ensure that only one gene will be targeted. 

Recently, a putative mixed-link (/3-1,3/1,4)-glucanase gene was identified within a EST library of in p/arafa-expressed genes of C. purpurea (see below), perhaps opening the way for a functional analysis also of this enzyme system. 

Within an EST library of C. purpurea (see below), a gene encoding a classical (single-unit) class II hydrophobin (cphl) has been detected the gene is expressed in most stages of infection and is induced by copper (see above), but a specific role has not yet been assigned to it. 

Based on known cinnamate 4-hydroxylase sequences from Jerusalem artichoke and mung bean a homology search in an EST library identified an EST clone with 84-86% sequence identity, which was then used as a probe to isolate the CYP73A5 from a genomic library. ... 

Comparison of the number of EST-clones corresponding to each of the PttCesA genes in the different hybrid aspen EST libraries revealed that, similar to Arabidopsis, different sets of CesA genes seem to characterize primary and secondary cell wall synthesis (Figure 6-4) (Djerbi et al. 2004). 

Figure 6-4. Relative abundance of the ten different PttCesA clones in the different tissue specific EST libraries from Populus tremula (L.) x tremuloides (Michx.). Data from Djerbi et al. 2003 See Color Plate of this figure beginning on page 355)...

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