| Autor: |
Upadhyay-Tiwari N; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan., Huang XJ; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan., Lee YC; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan., Singh SK; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan., Hsu CC; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan., Huang SS; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan., Verslues PE; Institute of Plant and Microbial Biology, Academia Sinica, Taipei 11529, Taiwan. |
| Abstrakt: |
The mechanisms of plant drought resistance are unclear but may involve membrane trafficking and metabolic reprogramming, including proline accumulation. Forward genetic screening using a proline dehydrogenase 1 ( ProDH1 ) promoter:reporter identified a drought hypersensitive mutant with a single-amino acid substitution (P335L) in the nonphototrophic hypocotyl 3 (NPH3) domain of NPH3/root phototropism 2-like 5 (NRL5)/naked pins in Yucca 8 (NPY8). Further experiments found that NRL5 and other NPH3 domain proteins are guanosine triphosphatases (GTPases). NRL5, but not NRL5 P335L , interacted with the RABE1c and RABH1b GTPases and the soluble N -ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) Vesicle-Associated Membrane Protein (VAMP)721/722. These proteins controlled NRL5 localization and connection to trafficking while also being genetically downstream of, and potentially regulated by, NRL5. These data demonstrate that NRL5-mediated restraint of proline catabolism is required for drought resistance and also reveal unexpected functions of the NPH3 domain such that the role of NPH3 domain proteins in signaling, trafficking, and cellular polarity can be critically reevaluated. |
