Lisa Ruthig at Wistar Institute writes:
>In article <2s627i$d9s at nwfocus.wa.com>, venezia at zgi.com (Domenick Venezia)
>wrote:
>>>> Sidney Shall says that the RNA moiety has been cloned but the protein
>> moiety has not been. I'm not sure which organisms Sidney is talking about,
>> but at least the yeast protein moiety has been cloned. Lundblad, V. and
>> Szostak, J.W. "A Mutant with a Defect in Telomere Elongation Leads to
>> Senescence in Yeast", Cell 57:633-643. Search for locus EST1 in
>> PIR and/or EST1_YEAST in SWISS-PROT. The RNA moiety has been cloned from
>> about 8 ciliates (Cell 67:343-353).
>>>From " An Alternative Pathway for Yeast Telomerase Maintenance Rescues
>ext1- Senescence," Cell 73:347-360 Lundblad and Blackburn:
>>EST1 mutants show a continuous decline in telomere length and increases
>in frequency of cell death and chromosome loss. "These phenotypes are
>consistent with the hypothesis that the EST1 gene encodes an essential
>component of the yeast telomere replication machinery, such as telomerase,
>although other mechanisms for the failure to replicate telomeres are not
>excluded."
>> Note that they do not claim to have definitely cloned telomerase.
I agree that they do not state that, and in fact in a review of the
references immediately at my disposal no one in an original paper makes
the statement. So I stand corrected and allow me to ammend my previous
statement to state that a putative telomerase has been cloned.
Domenck Venezia
ZymoGenetics
Seattle, WA
venezia at zgi.com