Species	Reference gene ID	Possible function	Papers / DOI
Arabidopsis	At1g05180	Regulatory subunit of the dimeric ECR1-AXR1 E1 enzyme.	Multiple ubiquitin ligase-mediated processes require COP9 signalosome and AXR1 function.; 2002; DOI: 10.1105/tpc.003434; PMID: 12368504; https://pubmed.ncbi.nlm.nih.gov/12368504/ | AXL and AXR1 have redundant functions in RUB conjugation and growth and development in Arabidopsis.; 2007; DOI: 10.1111/j.1365-313x.2007.03211.x; PMID: 17655650; https://pubmed.ncbi.nlm.nih.gov/17655650/ | AXR1-ECR1 and AXL1-ECR1 heterodimeric RUB-activating enzymes diverge in function in Arabidopsis thaliana.; 2011; DOI: 10.1007/s11103-011-9750-8; PMID: 21311953; https://pubmed.ncbi.nlm.nih.gov/21311953/ | Crossover localisation is regulated by the neddylation posttranslational regulatory pathway.; 2014; DOI: 10.1371/journal.pbio.1001930; PMID: 25116939; https://pubmed.ncbi.nlm.nih.gov/25116939/ | Arabidopsis auxin-resistance gene AXR1 encodes a protein related to ubiquitin-activating enzyme E1.; 1993; DOI: 10.1038/364161a0; PMID: 8321287; https://pubmed.ncbi.nlm.nih.gov/8321287/
Arabidopsis	At2g32410	Regulatory subunit of the dimeric ECR1-AXL1 E1 enzyme.	AXR1-ECR1 and AXL1-ECR1 heterodimeric RUB-activating enzymes diverge in function in Arabidopsis thaliana.; 2011; DOI: 10.1007/s11103-011-9750-8; PMID: 21311953; https://pubmed.ncbi.nlm.nih.gov/21311953/