Mutation of Arabidopsis Plastid Phosphoglucose Isomerase Affects Leaf Starch Synthesis and Floral Initiation
Resource
Plant Physiol 123 (1): 319-326
Journal
PLANT PHYSIOLOGY
Pages
319-326
Date Issued
2000
Date
2000
Author(s)
Yu, Tien-Shin
Lue, Wei-Ling
Wang, Shue-Mei
Chen, Jychian
Abstract
We isolated pgi1-1, an Arabidopsis mutant with a decreased plastid phospho-glucose (Glc) isomerase activity. While pgi1-1 mutant has a deficiency in leaf starch synthesis, it accumulates starch in root cap cells. It has been shown that a plastid transporter for hexose phosphate transports cytosolic Glc-6-P into plastids and expresses restricted mainly to the heterotrophic tissues. The decreased starch content in leaves of the pgi1-1 mutant indicates that cytosolic Glc-6-P cannot be efficiently transported into chloroplasts to complement the mutant's deficiency in chloroplastic phospho-Glc isomerase activity for starch synthesis. We cloned the Arabidopsis PGI1 gene and showed that it encodes the plastid phospho-Glc isomerase. The pgi1-1 allele was found to have a single nucleotide substitution, causing a Ser to Phe transition. While the flowering times of the Arabidopsis starch-deficient mutants pgi1, pgm1, and adg1 were similar to that of the wild type under long-day conditions, it was significantly delayed under short-day conditions. The pleiotropic phenotype of late flowering conferred by these starch metabolic mutations suggests that carbohydrate metabolism plays an important role in floral initiation.
SDGs
File(s)![Thumbnail Image]()
Loading...
Name
05.pdf
Size
286.13 KB
Format
Adobe PDF
Checksum
(MD5):3b614df7871fc71e8975cb1fbf07d70e