Search

Several type III effector proteins from Pseudomonas syringae have been shown to be targeted to the host plasma membrane. In the same study it was shown that efficient membrane association enhances function. Plant innate immune systems evolved disease resistance genes to recognize some type III effectors, Avirulence (Avr) proteins.

The alpha-TIP (tonoplast intrinsic proteins) and the TIP-Ma27 antibodies defines the functional implications of the compartments of protein vacuoles. The alpha-TIP defines a compartment for protecting storage-type proteins from enzyme degradation. The TIP-Ma27 defines a separate acidic lytic compartment. Barley lectin vacuolar proteins were detected in alpha-TIP vacuoles while aleurain proteins were contained in TIP-Ma27. This mechanism indicates a receptor-mediated pathway for two separate vacuolar compartments.

The movement of proteins into the peroxisomal lumen involves the recognition of a peroxisomal targeting signal (PTS) by its cognate receptors. The receptors target the proteins to the translocation pathway. Proteins without a PTS associate with the PTS-containing proteins to penetrate the peroxisome. The PTS1 receptors of yeast and humans are structurally similar. In human peroxisomal diseases, the translocation of proteins is defective. Peroxisomes are able to translocate oligomeric proteins unlike the mitochondria and chloroplast.

Analysis of the role of spore coat proteins in Dictyostelium discoideum by comparing the integrity of spores in wild-type strains and strains deficient in SP96, SP60 or SP70 spore coat proteins reveals that the spore coat proteins generate a protective outer layer for the spores but are not necessary for the development and structural feature determination of the spores. The spores in the mutant strains are similar to those in the wild-type strains but are sensitive to ricin A staining. Decrease in the spore coat proteins enhances the intensity of staining.