Comparison of features distinguishing plateins from other articulins
| . | Articulins . | Plateins . |
|---|---|---|
| Cellular location | Cytoplasmic (sub-plasmalemmal) | Within membranous cisternae (intra-alveolar) |
| N-terminal signal sequence | Absent | Present |
| Major repetitive domain (`core') | VP-rich 12-mers (VPVPV...) | VP-rich 12-mers (VP-charged) |
| Second repetitive domain (number of repeats) | Pseudomicrothorax dubius: | 5-mers (P-rich, no G) |
| ||
| Euglena gracilis: | α1,2: N-terminal (15; 14) | |
| β/γ: C-terminal (17) | |
| Charged amino acids: total (%) (net charge) | P. dubius: | α1: 24.3% (-47) |
| α2: 24.0% (-39) | |
| E. gracilis: | β/γ: 29.4% (-34) | |
| ||
| Predicted pI: entire protein (`core' domain only) | P. dubius: | α1: 4.75 (4.43) |
| α2: 4.77 (4.39) | |
| E. gracilis: | β/γ: 4.88 (4.66) | |
| ||
| Anomalous gel retardation (gene-derived versus SDS-PAGE Mrs; `n'=apparent gel Mr) | P. dubius: | |
| α: 56.3-60.9 →→ `125' kDa | |
| E. gracilis: | β/γ: 72.8 →→ `95-99' | |
|
| . | Articulins . | Plateins . |
|---|---|---|
| Cellular location | Cytoplasmic (sub-plasmalemmal) | Within membranous cisternae (intra-alveolar) |
| N-terminal signal sequence | Absent | Present |
| Major repetitive domain (`core') | VP-rich 12-mers (VPVPV...) | VP-rich 12-mers (VP-charged) |
| Second repetitive domain (number of repeats) | Pseudomicrothorax dubius: | 5-mers (P-rich, no G) |
| ||
| Euglena gracilis: | α1,2: N-terminal (15; 14) | |
| β/γ: C-terminal (17) | |
| Charged amino acids: total (%) (net charge) | P. dubius: | α1: 24.3% (-47) |
| α2: 24.0% (-39) | |
| E. gracilis: | β/γ: 29.4% (-34) | |
| ||
| Predicted pI: entire protein (`core' domain only) | P. dubius: | α1: 4.75 (4.43) |
| α2: 4.77 (4.39) | |
| E. gracilis: | β/γ: 4.88 (4.66) | |
| ||
| Anomalous gel retardation (gene-derived versus SDS-PAGE Mrs; `n'=apparent gel Mr) | P. dubius: | |
| α: 56.3-60.9 →→ `125' kDa | |
| E. gracilis: | β/γ: 72.8 →→ `95-99' | |
|
Articulins described from the ciliate P. dubius(Huttenlauch et al., 1998a)and the euglenoid flagellate E. gracilis(Marrs and Bouck, 1992) are used to represent the standard articulins. Amino acid composition and pI predictions for entire proteins (minus signal sequences for the plateins) and the major repeat core domains were derived using the ProtParam tool (ExPASy proteomics server of the Swiss Institute of Bioinformatics).