Table 4.
Capacity of E. coli-expressed R. communis phloem sap proteins to move from cell to cell when microinjected into mesophyll cells within the cotyledons of C. maxima plants
| Injected material | Protein concentration, mg⋅ml−1 | Micro- injections* | Extent of movement |
|---|---|---|---|
| LYCH | — | 18 (18; 100%) | 20–30 cells |
| 20-kDa FD | — | 0 (18; 0%) | 0 cells |
| FITC-glutaredoxin | 5.0 | 10 (17; 59%) | 10–12 cells |
| Glutaredoxin + 20-kDa FD | 2.5 | 6 (12; 50%) | 10–12 cells |
| Glutaredoxin + 40-kDa FD | 2.5 | 1 (12; 8%) | 4 cells† |
| FITC-cystatin | 2.3 | 5 (11; 45%) | 10–12 cells |
| Cystatin + 20-kDa FD | 1.7 | 6 (12; 50%) | 10–12 cells |
| Cystatin + 40-kDa FD | 1.7 | 1 (10; 10%) | 3 cells† |
| Ubiquitin‡ + 20-kDa FD | 1.0 | 1 (10; 10%) | 3 cells† |
| FITC-ubiquitin§ | 3.0 | 0 (16; 0%) | 0 cells |
| FITC-ΔC-ubiquitin§ | 3.0 | 2 (12; 16%) | 3–4 cells† |
| FITC-ΔC-ubiquitin§ + PP2 | 2.0 + 2.0 | 0 (8; 0%) | 0 cells |
| FITC-ΔC-ubiquitin§ + KN1 | 2.0 + 2.0 | 1 (10; 10%) | 3 cells† |
FD, FITC-dextran.
*
Details as in Table 1.
†
When movement of fluorescence was detected, it was confined to adjacent cells.
‡
Ubiquitin extracted from the phloem sap of R. communis.
§
E. coli-expressed A. thaliana ubiquitin (wild-type) and ΔC-ubiquitin (C-terminal deletion mutant).