Title: Characterization of calcium oxalate defective (cod) 3 mutant from Medicago truncatula Authors
|Mcconn, Michelle -|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2009
Publication Date: N/A
Technical Abstract: Many plants invest a considerable amount of resources and energy into the formation of calcium oxalate crystals. Assigned roles for plant crystal formation include functions in defense, calcium regulation, and aluminum tolerance. From a human health standpoint, oxalate present in edible plant tissues can act as an anti-nutrient and potential toxin. Although calcium oxalate plays important roles in plant development and impacts human health, the mechanisms regulating plant crystal formation remain unknown. To gain insight into these mechanisms we initiated a mutant screen to identify the genetic determinants. In this study we report the characterization of one of these mutants, cod3, which was isolated from an EMS-mutagenized Medicago truncatula population by visually screening for alterations in crystal formation. Microscopic examination of the cod3 revealed that this mutant had an increase in crystal number compared to wild type. This increase in calcium oxalate formation was confirmed by measuring calcium and oxalate levels. The mutant had a similar amount of calcium and about 38% more oxalate than wild type. Genetic mapping studies were conducted as an initial step toward positional cloning of the affected gene. The presented studies indicate that the cod3 is important in maintaining cell-specific crystal deposition and that disruption of the normal encoded function results in an expansion of the crystal accumulation profile. It is our hope that the information gained through the characterization and analysis of such calcium oxalate mutants will be applicable toward future efforts to improve the production and nutritional content of plant foods.