A SINGLE-LOCUS ON HUMAN-CHROMOSOME-21 DIRECTS THE EXPRESSION OF A RECEPTOR FOR ADENOVIRUS TYPE-2 IN MOUSE A9 CELLS

The receptors on human cells which mediate adsorption of adenoviruses hare not been identified. We found that murine A9 cells and Chinese ha mster ovary (CHO) cells failed to bind significant levels of radiolabe led adenovirus type 2 (Ad2) virions but that derivatives of these cell s carrying human chromosome 21 exhibited high levels of virus binding that was specific for the viral fiber protein. G418-resistant A9 cell transformants expressing Ad2 receptors were detected at a frequency of about 10(-4) following cotransfection with high-molecular-weight DNAs from mouse cells containing human chromosome 21 and plasmid DNA conta ining a neomycin resistance gene. The Ad2 receptors on the transformed A9 cells were similar to those on human cells with respect to their c oncentration on the cell membrane, their affinity for the viral fiber protein, and their ability to direct virus into cells along a pathway leading to delivery of the viral DNA genome into the cell nucleus. Fur thermore, identical human DNA fragments were present in three independ ent mouse cell transformants expressing Ad2 receptors, supporting the conclusion that these human DNA fragments correspond to a gene or locu s on chromosome 21 that directs the expression of Ad2 receptors in the se cells.