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<div>In plants, immunity mediated by nucleotide-binding leucine-rich repeat (NLR) immune receptors often requires the formation of NLR hetero-pairs. As the partner has not yet been identified for the Arabidopsis NLR SUPRESSOR OF NPR1, CONSTITUTIVE 1 (SNC1), a reverse genetic screen was undertaken and the NLRs SIDEKICK SNC1 1 (SIKIC1), SIKIC2, and SIKIC3 were found to be redundantly required for SNC1-mediated defense. IP-MS analyses indicated that the SIKICs indeed interact with SNC1 as typical NLR pairs. Furthermore, the protein levels of the SIKICs are regulated by either MUTANT, <i>SNC1</i>-ENHANCING 1 (MUSE1) or MUSE2, two previously uncharacterized redundant E3 ubiquitin ligases that were identified from a genetic screen for <i>snc1</i> enhancers. As SNC1 accumulation is regulated by the E3 ligase SCF^CPR1, this report provides the first evidence that the homeostasis of individual components of a typical NLR pair are subject to differential regulation via ubiquitin-mediated protein degradation.</div>