Mutant Name: gcs1-2
| Gene Name | GCS1 |
| Protein Name | alpha-glucosidase I |
| Mutagen | T-DNA |
| Category | forward genetics |
| Organism | Arabidopsis thaliana |
| Ecotype | Ws |
| Donor | |
| General Description |
1. Mutants produce abnormal shrunken seeds, the morphogenesis of gcs1-1 embryos blocked at the heart stage of development. 2.The mutant seeds accumulate a low level of storage proteins, have no typical protein bodies, display abnormal cell enlargement and show occasional cell wall disruptions. 3. Biochemical analyses have confirmed that trimming of the alpha1,2- linked glucosyl residue constitutive of the N-glycan precursor is blocked in this mutant. 4.Sequencing of the mutated gene revealed that a T-DNA was inserted in the 15th intron between nucleotides 4627 and 4688 (Figure 2). Thus, the insertion gave rise to a small deletion of the genomic DNA (60 bp). |
| Organ Specificity | GCS1 mRNA was detected in all the tissues tested, at a similar level. The results suggested that the expression of GCS1 is constitutive. |
| Impact on Wall |
1.In contrast to wild-type embryos, the radicle and cotyledons did not elongate to form a torpedo shape. Instead, embryos increased in size by radial cell expansion, leading to the filling of the whole seed. 2.The number of cell layers was not modified in hypocotyls and cotyledons of mutant embryos compared with wild-type embryos at the heart stage of development. 3.cell wall disruptions were occasionally observed in mutant cells. |
| Impact on Sugar Composition | |
| Reference | Boisson M, Gomord V, Audran C, Berger N, Dubreucq B, Granier F, Lerouge P, Faye L, Caboche M, Lepiniec L. Arabidopsis glucosidase I mutants reveal a critical role of N-glycan trimming in seed development. EMBO J. 2001 Mar 1;20(5):1010-9. |