Affiliation: | aLaboratory of Structural Biology, National Institute of Arthritis, Musculoskeletal and Skin Diseases, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, 20892;bNational Institute of Arthritis, Musculoskeletal and Skin Diseases, Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, 20892 |