hCG and hyperglycosylated
hCG : the horror stories of the evolution of pregnancy
failures :: Learn more
about Hormone Family
The glycoprotein hormone family of molecules all evolved from TGFβ over
hundreds of millions of years. In many respects, the stories of humans and
evolution of hCG and hyperglycosylated hCG are all interrelated. Unfortunately,
these stories are also one and the same with the horror stories of the
evolution of pregnancy failures and the evolution of human cancers. This is
because the evolution of hCG and hyperglycosylated hCG led to the evolution of
humans, and led to human pregnancy failures and human malignancies. All are all
driven by variants of hCG and hyperglycosylated hCG.
Glycoprotein
Hormones:-
The glycoprotein hormone
family includes TSH, and the two gonadotropins. The three glycoprotein hormones are synthesized
and stored in pituitary basophils and,
as their name implies, each contains sugar moieties covalently linked to asparagine residues
in the polypeptide
chains. All three are comprised
of two peptide subunits, designated alpha and beta, which, though tightly coupled,
are not covalently linked. The alpha
subunit of all three
hormones is identical in its amino
acid sequence, and is the product of a
single gene located on chromosome
6.But the beta
subunits of each are somewhat
larger than the alpha subunit and confer physiological specificity. Both alpha
and beta subunits contribute to receptor
binding and both must be
present in the receptor binding pocket to produce a biological response.
Beta subunits are encoded in separate genes located on different chromosomes:for
example :- TSH β on chromosome
1, FSH β on chromosome
11, and LH β on chromosome
19, but there is a great
deal of homology in their amino acid sequences. Both subunits contain
carbohydrate moieties that are considerably less constant in their composition
than are their peptide chains. Alpha subunits are synthesized in excess over
beta subunits, and hence it is synthesis of beta subunits that appears to be
rate-limiting for production of glycoprotein hormones. Pairing of the two
subunits begins in the rough
endoplasmic reticulum and continues in the Golgi
apparatus, where processing of
carbohydrate components of the subunits is completed. The loosely paired
complex then undergoes spontaneous refolding in secretory
granules into a stable,
active hormone. Control of expression of the alpha and beta subunit genes is
not perfectly coordinated, and free alpha and the beta subunits of all three
hormones may be found in blood plasma.

The glycoproteins.
Which
genes control synthesis * & later controlled release of abnormal molecules hCG molecules(phantom hCG)??The placental
hormone, human chorionic gonadotropin (hCG), is closely related chemically and
functionally to the pituitary gonadotropic hormones. It, too, is a glycoprotein
and consists of an alpha and a beta chain. The alpha chain is a product of the
same gene as the alpha chain of pituitary glyco-protein hormones. The peptide sequence of the beta
chain is identical to that of LH except that it is longer by 32 amino acids at
its carboxyl terminus.
Curiously, although
there is only a single gene for each beta subunit of the pituitary
glyco-protein hormones, the human
genome contains 7 copies of the hCG beta gene, all located on chromosome 19
in close proximity to the LH beta gene. Not surprisingly, hCG has biological
actions that are similar to those of LH, as well as a unique action on the
corpus luteum
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