Arabidopsis DDB1-CUL4 ASSOCIATED FACTOR1 forms a nuclear E3 ubiquitin ligase with DDB1 and CUL4 that is involved in multiple plant developmental processes.
The human DDB1-CUL4 ASSOCIATED FACTOR (DCAF) proteins have been reported to interact directly with UV-DAMAGED DNA BINDING PROTEIN1 (DDB1) through the WDxR motif in their WD40 domain and function as substrate-recognition receptors for CULLIN4-based E3 ubiquitin ligases. Here, we identified and characterized a homolog of human DCAF1/VprBP in Arabidopsis thaliana. Yeast two-hybrid analysis demonstrated the physical interaction between DCAF1 and DDB1 from Arabidopsis, which is likely mediated via the WD40 domain of DCAF1 that contains two WDxR motifs. Moreover, coimmunoprecipitation assays showed that DCAF1 associates with DDB1, RELATED TO UBIQUITIN-modified CUL4, and the COP9 signalosome in vivo but not with CULLIN-ASSOCIATED and NEDDYLATION-DISSOCIATED1, CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1), or the COP10-DET1-DDB1 complex, supporting the existence of a distinct Arabidopsis CUL4 E3 ubiquitin ligase, the CUL4-DDB1-DCAF1 complex. Transient expression of fluorescently tagged DCAF1, DDB1, and CUL4 in onion epidermal cells showed their colocalization in the nucleus, consistent with the notion that the CUL4-DDB1-DCAF1 complex functions as a nuclear E3 ubiquitin ligase. Genetic and phenotypic analysis of two T-DNA insertion mutants of DCAF1 showed that embryonic development of the dcaf1 homozygote is arrested at the globular stage, indicating that DCAF1 is essential for plant embryogenesis. Reducing the levels of DCAF1 leads to diverse developmental defects, implying that DCAF1 might be involved in multiple developmental pathways.
Peking-Yale Joint Center of Plant Molecular Genetics and Agrobiotechnology, College of Life Sciences, Peking University, Beijing 100871, China.
Yu
Y
Zhang
Suhua
S
Feng
Fangfang
F
Chen
Haodong
H
Chen
Jia
J
Wang
Chad
C
McCall
Yue
Y
Xiong
Xing Wang
XW
Deng
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D044842:Cullin Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D006801:Humans; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D019697:Onions / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000196:embryology / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D044767:Ubiquitin-Protein Ligases
D029681:Arabidopsis Proteins; C514806:CULLIN4 protein, Arabidopsis; D044842:Cullin Proteins; C088435:DET1 protein, Arabidopsis; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; C036483:T-DNA; C450820:COP10 protein, Arabidopsis; D044763:Ubiquitin-Conjugating Enzymes; C471983:AT2G32950 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases