InterPro domain: IPR034361

This entry represents the RNA recognition motif 1 (RRM1) of PHIP1. A. thaliana PHIP1 and its homologues represent a novel class of plant-specific RNA-binding proteins that may play a unique role in the polarized mRNA transport to the vicinity of the cell plate [ 1 ]. PHIP1 is a peripheral membrane protein and is localized at the cell plate during cytokinesis in plants. In addition to phragmoplastin, PHIP1 interacts with two Arabidopsis small GTP-binding proteins, Rop1 and Ran2. However, PHIP1 interacted only with the GTP-bound form of Rop1 but not the GDP-bound form. It also binds specifically to Ran2 mRNA [ 2 ]. This group of proteins consist of multiple functional domains, including a lysine-rich domain (KRD domain) that contains three nuclear localization motifs (KKKR/NK), two RNA recognition motifs (RRMs), and three CCHC-type zinc fingers.

1. A novel RNA-binding protein associated with cell plate formation. Plant Physiol. 148, 223-34
2. Perinuclear and nuclear envelope localizations of Arabidopsis Ran proteins. Plant Cell Rep. 26, 1373-82