Mutant Name: acw1(altered cell wall 1)
| Gene Name | KOR1 |
| Protein Name | glucanase (endo, membrane-bound) |
| Mutagen | EMS |
| Category | forward genetics |
| Organism | Arabidopsis thaliana |
| Ecotype | Col |
| Donor | |
| General Description |
1.acw1 is a temperature-senditive allele of kor1. 2.At the non-permissive temperature of 31C, the mutation impaired tissue elongation; otherwise, tissue development was normal. Hypocotyl cells that had established cell walls at 21 C under light-dark cycles ceased elongation and swelled when the mutant was shifted to 31 C and darkness. 3.Mutants showed a strong reduction in crystaline cellulose at the restrictive temperature,which was compensated for by an increase in pectic material. 4.The recessive mutation was mapped to chromosome V, and map-based cloning identified it as a single GA transition (resulting in a Gly429 to Arg substitution) in KORRIGAN, which encodes a membrane-bound endo-beta-1,4-glucanase. |
| Organ Specificity | |
| Impact on Wall |
1.Field emission scanning electron microscopy suggested that the structure of cellulose bundles was affected by the mutation; X-ray diffraction, however, revealed no change in the crystallite size of cellulose microfibrils. 2.The regeneration of cellulose microfibrils from naked mutant protoplasts was substantially delayed at 31C. 3.The increased amounts of pectin in the mutant were bound tightly to cellulose microfibrils. |
| Impact on Sugar Composition |
1.The cellulose content of mutants was reduced to 40% and the pectin content was increased to 162% of the corresponding values for the wild type. 2. No change in the content of hemicellulose was apparent in the 31 C-adapted mutant. |
| Reference | Sato S, Kato T, Kakegawa K, Ishii T, Liu YG, Awano T, Takabe K, Nishiyama Y, Kuga S, Sato S, Nakamura Y, Tabata S, Shibata D. Role of the putative membrane-bound endo-1,4-beta-glucanase KORRIGAN in cell elongation and cellulose synthesis in Arabidopsis thaliana. Plant Cell Physiol. 2001 Mar;42(3):251-63. |