InterPro domain: IPR044700

This entry includes PAMP-induced secreted peptide 2 (PIP2) and PAMP-INDUCED PEPTIDE-LIKE 1 (PIPL1, also known as CEP16 or PREPIPL1) from Arabidopsis, which are part of the PIP/PIPL family [ 1 , 2 ]. These secreted proteins contain two conserved core SGPS motifs at the C terminus and the GxGH motif at the extreme C terminus [ 3 ]. The double peptide motif might be processed into two different peptides or, alternatively, may act as a functional unit, being able to interact with distinct binding sites resulting in the activation of different pathways. PIP2 is involved in innate immune and stress responses. It also acts as a negative regulator of root growth [ 3 ]. PIPL1 is involved in seed development and was also induced by stress [ 3 ].

1. The secreted peptide PIP1 amplifies immunity through receptor-like kinase 7. PLoS Pathog. 10, e1004331
2. The IDA/IDA-LIKE and PIP/PIP-LIKE gene families in Arabidopsis: phylogenetic relationship, expression patterns, and transcriptional effect of the PIPL3 peptide. J Exp Bot 66, 5351-65