Mutant Name: sos5
| Gene Name | SOS5 |
| Protein Name | Adhesion Protein (putative) |
| Mutagen | EMS |
| Category | forward genetics |
| Organism | Arabidopsis thaliana |
| Ecotype | Col |
| Donor | |
| General Description |
1. Root growth of sos5 plants is hypersensitive to salt stress but not osmotic stress caused by mannitol. 2.The predicted SOS5 protein contains an N-terminal signal sequence for plasma membrane localization, two arabinogalactan protein-like domains, two fasciclin-like domains, and a C-terminal glycosylphosphatidylinositol lipid anchor signal sequence. 3. The SOS5 protein was present at the outer surface of the plasma membrane. |
| Organ Specificity | 1.The sos5 mutant has root-swelling phenotype under salt stress. 2.During vegetative growth in soil, sos5 rosette-stage plants had slightly larger leaves with longer petioles than wild-type plants. 3.sos5 plants produced shorter siliques. |
| Impact on Wall |
1. Under salt stress, the root tips of sos5 mutant plants swell and root growth is arrested. The root-swelling phenotype is caused by abnormal expansion of epidermal, cortical, and endodermal cells. 2. In the sos5 mutant, the middle lamella was missing and the primary cell walls appeared less organized than those of the wild type. In addition, the cell walls in sos5 were thinner than those in the wild type. In the tips of roots treated with 100 mM NaCl, the cell membrane appeared less tightly attached to the wall in sos5 than in the wild type |
| Impact on Sugar Composition | |
| Reference | 1. Shi H, Kim Y, Guo Y, Stevenson B, Zhu JK. The Arabidopsis SOS5 locus encodes a putative cell surface adhesion protein and is required for normal cell expansion. Plant Cell. 2003 Jan;15(1):19-32. |