Mutant Name: fra7
| Gene Name | SAC1 |
| Protein Name | Phosphoinositide Phosphatase |
| Mutagen | EMS |
| Category | forward genetics |
| Organism | Arabidopsis thaliana |
| Ecotype | Col |
| Donor | |
| General Description |
1.Mutation of the AtSAC1 gene in the fragile fiber7 (fra7) mutant caused a dramatic decrease in the wall thickness of fiber cells and vessel elements, thus resulting in a weak stem phenotype. 2.The fra7 mutation also led to reduced length and aberrant shapes in fiber cells, pith cells, and trichomes and to an alteration in overall plant architecture. |
| Organ Specificity | The AtSAC1 gene was found to be expressed in all tissues in elongating organs; however, it showed predominant expression in vascular tissues and fibers in nonelongating parts of stems. |
| Impact on Wall |
1.The force required to break the basal mature stems was four times lower in fra7 compared with the wild type. 2.Examination of fiber wall thickness by transmission electron microscopy revealed that the wall thickness of fra7 fiber cells was reduced to 51% of that of the wild type. |
| Impact on Sugar Composition | crystalline cellulose in the mutant was reduced to 87% of that in the wild type. Cell wall sugar composition analysis revealed a slight decrease in the amount of glucose and xylose in the mutant compared with the wild type |
| Reference | Zhong R, Burk DH, Nairn CJ, Wood-Jones A, Morrison WH 3rd, Ye ZH. Mutation of SAC1, an Arabidopsis SAC Domain Phosphoinositide Phosphatase, Causes Alterations in Cell Morphogenesis, Cell Wall Synthesis, and Actin Organization. Plant Cell. 2005 May;17(5):1449-66. |