May act as a substrate-specific adapter of an E3 ubiquitin-protein ligase complex (CUL3-RBX1-BTB) which mediates the ubiquitination and subsequent proteasomal degradation of target proteins (By similarity). Acts redundantly with BOP2. BOP1/2 promote leaf and floral meristem fate and determinacy in a pathway targeting AP1 and AGL24. BOP1/2 act as transcriptional co- regulators through direct interaction with TGA factors, including PAN, a direct regulator of AP1. Controls lateral organ fate through positive regulation of adaxial-abaxial polarity genes ATHB-14/PHB, YAB1/FIL and YAB3, and through positive regulation of LOB domain-containing genes LOB, LBD6/AS2 and LBD36. Promotes and maintains a developmentally determinate state in leaf cells through the negative regulation of JAG, JGL and class I KNOX genes. Is also involved in nectary development, formation of normal abscission zones and suppression of bract formation. At2g41370 NPR5_ARATH Regulatory protein NPR5 Protein BLADE ON PETIOLE 2 BTB/POZ domain-containing protein NPR5 NPR5 F13H10.8 BOP2 491 MSNLEESLRSLSLDFLNLLINGQAFSDVTFSVEGRLVHAHRCILAARSLFFRKFFCGTDSPQPVTGIDPTQHGSVPASPTRGSTAPAGIIPVNSVGYEVFLLLLQFLYSGQVSIVPQKHEPRPNCGERGCWHTHCSAAVDLALDTLAASRYFGVEQLALLTQKQLASMVEKASIEDVMKVLIASRKQDMHQLWTTCSHLVAKSGLPPEILAKHLPIDVVTKIEELRLKSSIARRSLMPHNHHHDLSVAQDLEDQKIRRMRRALDSSDVELVKLMVMGEGLNLDESLALHYAVESCSREVVKALLELGAADVNYPAGPAGKTPLHIAAEMVSPDMVAVLLDHHADPNVRTVGGITPLDILRTLTSDFLFKGAVPGLTHIEPNKLRLCLELVQSAAMVISREEGNNSNNQNNDNNTGIYPHMNEEHNSGSSGGSNNNLDSRLVYLNLGAGTGQMGPGRDQGDDHNSQREGMSRHHHHHQDPSTMYHHHHQHHF