Fanconi anemia proteins FANCA, FANCC, and FANCG/XRCC9 interact in a functional nuclear complex.
Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome with at least eight complementation groups (A to H). Three FA genes, corresponding to complementation groups A, C, and G, have been cloned, but their cellular function remains unknown. We have previously demonstrated that the FANCA and FANCC proteins interact and form a nuclear complex in normal cells, suggesting that the proteins cooperate in a nuclear function. In this report, we demonstrate that the recently cloned FANCG/XRCC9 protein is required for binding of the FANCA and FANCC proteins. Moreover, the FANCG protein is a component of a nuclear protein complex containing FANCA and FANCC. The amino-terminal region of the FANCA protein is required for FANCG binding, FANCC binding, nuclear localization, and functional activity of the complex. Our results demonstrate that the three cloned FA proteins cooperate in a large multisubunit complex. Disruption of this complex results in the specific cellular and clinical phenotype common to most FA complementation groups.
Garcia-Higuera
I
I
Department of Pediatric Oncology, Dana-Farber Cancer Institute, Department of Pediatrics, Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Kuang
Y
Y
Näf
D
D
Wasik
J
J
D'Andrea
A D
AD
D000818:Animals; D018797:Cell Cycle Proteins; D002461:Cell Line, Transformed; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005199:Fanconi Anemia / Q000378:metabolism*; D052218:Fanconi Anemia Complementation Group C Protein; D052241:Fanconi Anemia Complementation Group G Protein; D051856:Fanconi Anemia Complementation Group Proteins; D006801:Humans; D009687:Nuclear Proteins; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D011817:Rabbits
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C497651:FANCC protein, human; C499909:FANCG protein, human; D052218:Fanconi Anemia Complementation Group C Protein; D052241:Fanconi Anemia Complementation Group G Protein; D051856:Fanconi Anemia Complementation Group Proteins; D009687:Nuclear Proteins; D011506:Proteins