Disease relevance of CSY1

• A gene for Arabidopsis mitochondrial CS was overexpressed in canola using an Agrobacterium tumefaciens-mediated system [1].

High impact information on CSY1

• We tested the hypothesis that peroxisomal citrate synthase (CSY) is required for carbon transfer from peroxisomes to mitochondria during respiration of triacylglycerol in Arabidopsis thaliana seedlings [2].
• Two genes encoding peroxisomal CSY are expressed in Arabidopsis seedlings, and seeds from plants with both CSY genes disrupted were dormant and did not metabolize triacylglycerol [2].
• These results suggest that peroxisomal CSY in Arabidopsis is not only a key enzyme of the glyoxylate cycle but also catalyzes an essential step in the respiration of fatty acids [2].
• These observations indicated that the transport of glyoxysomal citrate synthase is mediated by its N-terminal presequence and that the transport system is functional in all plant microbodies [3].
• Modulation of citrate metabolism alters aluminum tolerance in yeast and transgenic canola overexpressing a mitochondrial citrate synthase [1].

Biological context of CSY1

• Increased levels of CS gene expression and enhanced CS activity were observed in transgenic lines compared with the wild type [1].
• Searches of the Arabidopsis database revealed that there are several genes encoding putative citrate synthase and luminal binding protein [4].
• In strains that are deficient in the mitochondrial isoform of citrate synthase there is an up-regulation of the peroxisomal isoform [5].

Anatomical context of CSY1

• Thus, it appears that the CS polypeptides by ectopic expression of DcCS were processed into the mature form and localized in the mitochondria of A. thaliana [6].
• These included citrate synthase, which is known to be targeted to mitochondria, peroxisomes and glyoxysomes, and luminal binding protein, which is an ER (endoplasmic reticulum)-resident protein [4].

Associations of CSY1 with chemical compounds

• A hybrid Arabidopsis variety was generated which accumulates two kinds of originally bacterial proteins, beta-glucuronidase (GUS) and a GUS chimeric protein designated as CS-delta C42-GUS, that carries the N-terminal targeting signal for glyoxysomal citrate synthase [7].

Other interactions of CSY1

• Recombinant AtFKBP42 prevents aggregation of citrate synthase in almost equimolar concentrations, and can be cross-linked to calmodulin [8].

References