Plant-specific insert

The plant-specific insert (PSI) or plant-specific sequence (PSS) is an independent domain, exclusively found in plants, consisting of approximately 100 residues, found on the C-terminal lobe on some aspartic proteases (AP) called phytepsins. The PSI, as an independent entity separate from its parent AP, is homologous to saposin and belongs to the saposin-like protein family (SAPLIP).

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