Table 1.
Comparison of the stomatin signal with other released morphogens involved in predator/prey interactions in aquatic environments
| Property | Source of signal
|
|||||
|---|---|---|---|---|---|---|
| Tetrahymena (ciliate) Stomatin signal | Chaoborus (midge) Kairomone | Asplanchna (rotifer) signal | Lembadion (ciliate) signal | Amoeba (ciliate) signal | Stenostomum (turbellarian) signal | |
| Appearance | Pale yellow to brownish | Pale yellow to brownish | — | — | — | — |
| Molecular mass | <1.8 kDa | <0.5 kDa | — | 31.5 kDa | 5–10 kDa | 17.5 kDa |
| Heat stable (>90°C) | Yes | Yes | No | No | — | No |
| Stable at low pH | Yes | Yes | — | — | — | — |
| Protease sensitive | No | No | Yes | Yes | Yes | Yes |
| Resin binding | ||||||
| Cationic | Yes | Weak | — | — | — | — |
| Anionic | No | Yes | — | — | — | — |
| Released by | Prey | Predator | Predator | Predator | Predator | Predator |
| Target organism | Polymorphic Tetrahymena | Daphnia (cladoceran) | Brachionus (rotifer) | Euplotes (ciliate) | Euplotes | Euplotes |
| Molecular form(s) | Multiple | Water: single Homogenate: multiple | Single | Single | Single | Single |
| Characterized as | Complexed hypoxanthine, uracil and Fe2+ | Nonolefinic hydroxyl-carboxylic acid | Protein | Polypeptide | Peptide | Polypeptide |
| Reference | (11, 12); this paper | (36, 37) | (32) | (29) | (30) | (31) |