Involved in disease resistance via the salicylic acid (SA) signaling pathway (PubMed:18315541, PubMed:27016096). Involved in shoot architecture development via the cytokinin signaling pathway (PubMed:18315541, PubMed:27016096). Interacts with RPT2A. A number of isoforms are produced. According to EST sequences. The LRR repeats probably act as specificity determinant of pathogen recognition. The gain-of-function mutant uni-1D (T-DNA tagging) exhibits bushy and severe dwarf phenotype, due to altered shoot architecture caused by enhanced axillary branch formation via the cytokinin pathway (PubMed:18315541). Uni-1D plants exhibit constitutive expression of pathogenesis-related (PR) genes through salicylic acid accumulation (PubMed:18315541). 'Uni' means sea urchin in Japanese (PubMed:18315541). Belongs to the disease resistance NB-LRR family. Functional and comparative genomics of disease resistance gene homologs