Subject: FlyBase query
Dear Dr. Frasch,
I am curating the paper Cai and Levine, 1997, EMBO J. 16: 1732--1741 for
FlyBase, in which a mod(mdg4) mutation obtained from you is used.
This mutation is called E(var)93D-P142.4D15 in the EMBO paper, and is
described in your paper:
Azpiazu and Frasch, 1993, Genes Dev. 7: 1325--1340, where it is called
P142delta15.
I have a number of questions about this mutation.
1. In the Materials and Methods section of the 1993 paper (top of page
1338, second column) you state that 'delta15 and delta32 also do not
complement the latter mutations' - the 'latter mutations' being in 'an
uncharacterized gene upstream of tin'. I would be grateful if you could
confirm whether this uncharacterized gene is in fact mod(mdg4).
2. Could you also confirm whether delta15, delta32, and the original
P(w+)142 insertion alter the expression of both tinman and the
uncharacterized gene (mod(mdg4)?), or if they just alter expression of one
of the genes ? In addition, what sequences are deleted in the delta15 and
delta32 mutants ?
I look forward to hearing from you,
Gillian Millburn
\--------------------------------------------------------------
Gillian Millburn.
FlyBase (Cambridge),
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>
Subject: Re: FlyBase query - answers
>Dear Dr. Frasch,
>
>I am curating the paper Cai and Levine, 1997, EMBO J. 16: 1732--1741 for
>FlyBase, in which a mod(mdg4) mutation obtained from you is used.
>
>This mutation is called E(var)93D-P142.4D15 in the EMBO paper, and is
>described in your paper:
>
>Azpiazu and Frasch, 1993, Genes Dev. 7: 1325--1340, where it is called
>P142delta15.
>
>I have a number of questions about this mutation.
>
>1. In the Materials and Methods section of the 1993 paper (top of page
>1338, second column) you state that 'delta15 and delta32 also do not
>complement the latter mutations' - the 'latter mutations' being in 'an
>uncharacterized gene upstream of tin'. I would be grateful if you could
>confirm whether this uncharacterized gene is in fact mod(mdg4).
It is mod(mdg4), which is also called E(var)3-93D (Dorn et al. 1993)
>
>2. Could you also confirm whether delta15, delta32, and the original
>P(w+)142 insertion alter the expression of both tinman and the
>uncharacterized gene (mod(mdg4)?), or if they just alter expression of one
>of the genes ? In addition, what sequences are deleted in the delta15 and
>delta32 mutants ?
>
P(w+)142 is inserted 27bp upstream of mod(mdg4) (based on the sequence of
the longest (at 5') class of cDNAs obtained). delta 15 deletes from here
into the transcribed region of mod(mdg). delta 32 deletes from here towards
the tin transcription start site, i.e., most of the intergenic region
between mod(mdg) and tin, but doesn't disrupt tin transcription unit - the
breakpoint is ca. 100bp upstream of tin). Neither of the two deletions show
an obvious reduction of tin expression, although they don't complement tin
mutations. The expression of mod(mdg) was not tested.
Please let me know in case you have additional questions.
Sincerely,
Manfred Frasch