Isolation and initial characterization of virescent mutants ofArabidopsis thaliana

✍ Scribed by Judy A. Brusslan; Elaine M. Tobin

• Publisher: Springer
• Year: 1995
• Tongue: English
• Weight: 413 KB
• Volume: 44
• Category: Article
• ISSN: 0166-8595
• DOI: 10.1007/bf00018298

✦ Synopsis

In higher plants, development of the chloroplasts must be coordinated with development of the leaf. In order to study the signals that synchronize these two developmental processes, we have isolated virescent (delayed in greening) mutants ofArabidopsis thaliana. Two such mutants that have pale-green young leaves which gradually green more fully during leaf maturation have been partially characterized. The two, virl and vir2, are due to separate nuclear recessive mutations. The pale leaves of virl and vir2 both had reduced 77 °K fluorescence emission at 730-734 nm relative to that at 686-687 nm, indicating a reduction in the relative amount of LHC I compared to WT. As leaves greened, the amount of LHC I increased to near wildtype levels. The shift in the fluorescence emission peak from 730 nm to 734 nm, characteristic of maturing LHC I, was seen for virl, but not vir2, suggesting that virl is a regulatory mutant while vir2 may be defective in a specific aspect(s) of LHC I function.