Doug! at nih.gov
Tue Mar 23 12:29:13 EST 1999
I noticed a misconception in your quiz that might be shared by other members
of this newsgroup. It is the concept that telomerase expression equals
telomere maintenance. This is not entirely true. The TRAP assay simply
determines the presence of telomerase in a cell extract. It does not prove
that the telomerase in the cell is actually maintaining the cell's
telomeres. There are other factors which, in addition to telomerase
expression, determine whether the telomeres shorten or not.
Therefore, telomerase expression by itself does not predict "unlimited
cellular proliferation." A good example is human lymphocytes, which have
transient expression of telomerase but still experience telomere shortening.
TIGER GIL wrote in link
Unlimited cellular proliferation is found in :
a. cancer cells
b. myeloma cells and stem cell lines
c. gastrointestinal crypt cells
d. hair follicular cells
e. all of the above
ans. e They have a transient expression of telomerase which leads to slowing
of the erosion rate of telomere bases.
ref. JAMA 1998 Jun 3;279(21):1732-5
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