Subunits of human sex hormone binding globulin. Interindividual variation in size.

摘要: Sex hormone binding globulin (SHBG), a dimeric plasma glycoprotein with molecular mass of about 90 kDa, was purified from healthy individuals by rapid two-step procedure using immunoaffinity chromatography on monoclonal antibody column followed fast protein liquid chromatography. The individual SHBGs so isolated were pure several criteria, and the overall yield usually 20% according to radioimmunoassay. analyzed polyacrylamide gel electrophoresis in presence sodium dodecyl sulfate which showed SHBG most subjects be composed subunits two different sizes (52 49 kDa) present approximate ratio 10:1 (double-banded SHBG). remaining contained third subunit an estimated 56 kDa (triple-banded In this kind SHBG, heavy approximately equal amounts, suggesting that triple-banded are heterozygotes for genetic variant protein. various separated individually subjected amino-terminal amino acid sequence analysis. They all had heterogeneous terminus, but since sequences obtained seemed identical, structural differences between would appear reside other parts molecules. On isoelectric focusing, both kinds resolved into 10 components, steroid-binding activity. Differences noted double-banded latter having greater abundance acidic species. Screening 121 involving small-scale isolation Western blotting revealed SHBG. This new found persons sexes children as well adults.