P-subunit of human chorionic gonadotropin

Figure 33. (a) Condensed schematic diagram of the P-subunit of human chorionic gonadotropin... 

Scheme 10 Synthesis of p-subunit of human chorionic gonadotropin hormone, p-hCG[l-145]...

The amino acid sequence of the a and P subunits of human chorionic gonadotropin is known. The a subunit contains 92, the p subunit 147 amino acid residues. Except for deletion of the N terminus in human LSH-a, the a subunits of human LSH and HCG are identical. The P subunits from HCG and human LSH differ by the deletion of 30 amino acid residues at the C terminus in LSH-j8 and by the carbohydrate placement. While human LSH-j5 has one site of carbohydrate attachment, HCG-jS has five. 

Blomberg, K., Hurskainen, P. and Hemmila, I. (1999). Terbium and rhodamine as labels in a homogeneous time-resolved fluorometric energy transfer assay of the b-subunit of human chorionic gonadotropin in serum. Clin. Chem. 45, 855-61. 

Policastro P, Ovitt CE, Hoshina M, Fukuoka H, Boothby MR, Boime I. The [3 subunit of human chorionic gonadotropin is encoded by multiple genes. J Biol Chem 1983 258 11492-9. 

Korhonen J, Alfthan H, Ylostalo P, Veldhuis J, Stenman UH. Disappearance of human chorionic gonadotropin and its alpha- and beta-subunits after term pregnancy Chn Chem 1997 43 2155-63. 

One of the most common home pregnancy tests is an immunoassay that detects the hormone human chorionic gonadotropin (hcG) in urine. HcG is a protein consisting of 244 amino acids in two subunits called a and p. The P subunit is unique to hcG, but the a subunit is found in some other proteins. The hormone begins to be secreted shortly after conception. 

Talwar, G. P., Sharma, N. C., Dubey, S. K.., etal., 1976, Isoimmunization against human chorionic gonadotropin with conjugates of processed beta-subunit of the hormone and tetanus toxoid. Proc Natl Acad Sci USA 73 218-22. 

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