InterPro domain: IPR027356

The NRL (for NPH3/RPT2-Like) family is formed by signaling molecules specificto higher plants. Several regions of sequence and predicted structuralconservation define members of the NRL family, with three domains being mostnotable: an N-terminal BTB domain, a centrally located NPH3domain, and a C-terminal coiled coil domain. The function of the NPH3 domainis not yet known [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ].

Some proteins known to contain a NPH3 domain include:

• Arabidopsis non-phototropic hypocotyl 3 (NPH3), may function as an adapter or scaffold protein in plants.
• Arabidopsis root-phototropisme 2 (RPT2), a signal transducer involved in phototropic response and stomatal opening in association with phototropin 1 (phot1).
• Oriza coleoptile phototropism 1 (CPT1), the rice ortholog of NPH3. It is required for phototropism of coleoptiles and lateral translocation of auxin.

This entry represents the NPH3 domain.

1. Arabidopsis NPH3: A NPH1 photoreceptor-interacting protein essential for phototropism. Science 286, 961-4
2. RPT2. A signal transducer of the phototropic response in Arabidopsis. Plant Cell 12, 225-36
3. RPT2 is a signal transducer involved in phototropic response and stomatal opening by association with phototropin 1 in Arabidopsis thaliana. Plant Cell 16, 887-96
4. The Rice COLEOPTILE PHOTOTROPISM1 gene encoding an ortholog of Arabidopsis NPH3 is required for phototropism of coleoptiles and lateral translocation of auxin. Plant Cell 17, 103-15
5. Regulation of phototropic signaling in Arabidopsis via phosphorylation state changes in the phototropin 1-interacting protein NPH3. J. Biol. Chem. 282, 19992-20001
6. Leaf positioning of Arabidopsis in response to blue light. Mol Plant 1, 15-26
7. Understanding phototropism: from Darwin to today. J. Exp. Bot. 60, 1969-78
8. Modulation of phototropic responsiveness in Arabidopsis through ubiquitination of phototropin 1 by the CUL3-Ring E3 ubiquitin ligase CRL3(NPH3). Plant Cell 23, 3627-40