Stiff backing. Presumptive null. This strain carries two CRISPR-engineered deletions to ensure complete knockout of ubr-1 function. hp821 is a deletion in the 5 ' end of ubr-1 and hp833 is a deletion near the 3' end of the gene. Reference: Chiturri J, et al. PLoS Genet. 2018 Apr 12;14(4):e1007303. doi: 10.1371/journal.pgen.1007303. eCollection 2018 Apr. PMID: 29649217.