[H]Amino acid selection of aminoacyl-tRNA synthetase mutants of CHO cells: Evidence of homo- vs. hemizygosity at specific loci.

Further application of the tritiated amino acid suicide selection procedure, designed to select conditional protein synthesis mutants, has yielded over 300 aminoacyl-tRNA synthetase mutants of Chinese hamster ovary cells, representing seven complementation groups. A number of these mutants and their revertants were used to examine the extent of X-chromosome linkage or other functional hemizygosity in CHO cells. Our results indicated that none of the seven different aaRS loci tested was X linked, and the the glnRS locus, unlike the asnRS and leuRS loci, does not appear to be functionally hemizygous in CHO cells. [ABSTRACT FROM AUTHOR]