Fig. 3.

The addition of leucine residues in the spotted hyena SHBG secretion polypeptide increases it production/secretion. The production of wild-type and mutant spotted hyena SHBG by CHO cells was determined by the ratio of SHBG concentration in the culture medium to SHBG mRNA in cells (shown above the horizontal brackets). The SHBG concentration in the medium was determined by a steroid-binding capacity assay, and the mRNA levels were determined by quantitative RT-PCR (see Materials and Methods for details). Data represent the means ± sd of triplicate cell cultures.