This is a family of sequences found exclusively in plants. They are similar to kinase interacting protein 1 (KIP1), which has been found to interact with the kinase domain of PRK1, a receptor-like kinase [1]. This particular region contains two coiled-coils, which are described as motifs involved in protein-protein interactions [1]. It has also been suggested that the protein's coiled- coils allow it to dimerise in vivo [1].

1: Isolation and characterization of kinase interacting protein 1, a pollen protein that interacts with the kinase domain of PRK1, a receptor-like kinase of petunia. Skirpan AL, McCubbin AG, Ishimizu T, Wang X, Hu Y, Dowd PE, Ma H, Kao T; Plant Physiol 2001;126:1480-1492. PMID:11500547