Subject: RE: AS-C question
Dear Aubrey:
I have checked our records on T7 and T9 and have asked Sonsoles
Campuzano who has a fantastic memory about data obtained long ago. As
far as we know, nobody has done anything else with these transcripts.
What we know is that T9 should be transcribed from somewhere else in the
genome, since Sonsoles observed it in Northerns containing RNA from the
sc2 = ase1 deletion, which removes its putative transcription unit. With
respect to T7, we did see it occasionally in our Northerns, but it
seemed to be removed by more stringent washing of the blots.
Incidentally, in Figure 2 of the Alonso and Cabrera paper I do not know
for sure which transcript corresponds to which blot since the size and
developmental profile of the T8 transcript (1.6 kb, present only in
embryos) is very different from what we found (2.8 kb, present in
embryos and late larva and early pupa; Gonzalez et al., 1989, EMBO J. 8,
3553-35623). And our results have been verified by the sequencing of
cDNAs, primer extension experiments ( which indicate a minimal size for
the mRNA, without the poly(A) tail, of 2.26 kb) and hybridizations in
situ (which demonstrated its presence in late larva and early pupa).
This is all I can say about these transcripts. I hope it is of some help.
You can cite my e-mail in the fly base. Take care. Best regards,
Juan