The carboxyl terminus of FANCE recruits FANCD2 to the Fanconi Anemia (FA) E3 ligase complex to promote the FA DNA repair pathway.
Fanconi anemia (FA) is a genome instability syndrome characterized by bone marrow failure and cellular hypersensitivity to DNA cross-linking agents. In response to DNA damage, the FA pathway is activated through the cooperation of 16 FA proteins. A central player in the pathway is a multisubunit E3 ubiquitin ligase complex or the FA core complex, which monoubiquitinates its substrates FANCD2 and FANCI. FANCE, a subunit of the FA core complex, plays an essential role by promoting the integrity of the complex and by directly recognizing FANCD2. To delineate its role in substrate ubiquitination from the core complex assembly, we analyzed a series of mutations within FANCE. We report that a phenylalanine located at the highly conserved extreme C terminus, referred to as Phe-522, is a critical residue for mediating the monoubiquitination of the FANCD2-FANCI complex. Using the FANCE mutant that specifically disrupts the FANCE-FANCD2 interaction as a tool, we found that the interaction-deficient mutant conferred cellular sensitivity in reconstituted FANCE-deficient cells to a similar degree as FANCE null cells, suggesting the significance of the FANCE-FANCD2 interaction in promoting cisplatin resistance. Intriguingly, ectopic expression of the FANCE C terminus fragment alone in FA normal cells disrupts DNA repair, consolidating the importance of the FANCE-FANCD2 interaction in the DNA cross-link repair.
Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, Florida 33620.
David
D
Polito
Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, Florida 33620.
Scott
S
Cukras
Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115.
Xiaozhe
X
Wang
Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, Florida 33620.
Paige
P
Spence
Cytogenetics Core Laboratory, Dana-Farber Cancer Institute, Boston, Massachusetts 02115.
Lisa
L
Moreau
Department of Radiation Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts 02115.
Alan D
AD
D'Andrea
Department of Cell Biology, Microbiology, and Molecular Biology, College of Arts and Sciences, University of South Florida, Tampa, Florida 33620. Electronic address: Ykee@usf.edu.
Younghoon
Y
Kee
D000595:Amino Acid Sequence; D004260:DNA Repair; D005199:Fanconi Anemia / Q000235:genetics / Q000378:metabolism*; D052236:Fanconi Anemia Complementation Group D2 Protein / Q000378:metabolism*; D052239:Fanconi Anemia Complementation Group E Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D052240:Fanconi Anemia Complementation Group L Protein / Q000378:metabolism; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D010649:Phenylalanine / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*; D054875:Ubiquitination
D052236:Fanconi Anemia Complementation Group D2 Protein; D052239:Fanconi Anemia Complementation Group E Protein; D010649:Phenylalanine; D052240:Fanconi Anemia Complementation Group L Protein; D044767:Ubiquitin-Protein Ligases
DNA Damage; DNA Repair; E3 Ubiquitin Ligase; Protein Degradation; Protein Dynamics; Protein Folding; Protein Targeting; Protein-protein Interactions; Ubiquitin