From stevaux@XXXX Tue Mar 12  00:00:45  2002
To: Rachel Drysdale (Genetics) <rd120@XXXX>,
Kevin Cook <kcook@XXXX>
Subject: Re: Are you interested?
Dear Rachel,
Here is a detailed description of deletions in the CG4287 and CG5516 genes.
The region is ordered as follow :
\-----CG4287----CG5516----------RBF2--moira---P2000----
P2000 is described in a previous communication about RBF2. P2000 is
male sterile at 25[o]C but fertile at 18[o]C and is inserted roughly
600bp upstream of moira.
I have hopped P2000 and created the following chromosome:
\-----CG4287---P16C3--CG5516----------RBF2--moira---P2000----
This new insertion P16C3 is viable and fertile at 18[o]C, 16C3 is
inserted exactly upstream of CG5516 (which doesn't have ESTs, so it
is debatable if it is a real gene) and 200 bp upstream of the
transcriptional start site of CG4287 (which does have an EST).
The line containing P16C3 and P2000 was crossed to the transposase
and precise deletions of the region between the 2 P-elements were
recovered. The deletions take out moira, RBF2, CG5516, and
potentially, bits of the CG4287 promoter as will become evident
later. The ends of the two P-elements are still intact and one
mini-white is still present in this background (from eye color and
PCR data).
\-----CG4287---P16C3--CG5516----------RBF2--moira---P2000----
\-----CG4287---[ 16C3 deletion
]---- (16C3 deletion, embryonic lethal)
This deletion is embryonic lethal. It is lethal over several moira alleles.
Genomic rescue constructs for moira were re-introduced. The
phenotype turned into a larval lethality. This deletion with moira in
the background complemented several null moira alleles Mor6 and Mor7.
\-----CG4287---[ 16C3 deletion
]-------<up>moira rescue</up>--- (larval lethal)
A genomic rescue construct covering RBF2, CG5516 and which cuts into
CG4287 DOES NOT rescue the larval lethality of the deletion with the
Moira rescue construct. However, a genomic rescue construct covering
CG4287 and CG5516 and which cuts into RBF2 RESCUES the larval
lethality. Hence, the larval lethality is due to the CG4287 gene.
The phenotype is as follow: small larvae (2nd or early 3rd instar)
crawl up the walls as if trying to pupate, but instead, they slow
down and die, turning black. Two stable stocks are available. One
has the 16C3 deletion, and the moira rescue construct and the other
has the 16C3 deletion and the RBF2, CG5516 genomic rescue construct.
When crossed to each other, the progeny displays the larval lethal
phenotype and specifically removes CG4287. If CG5516 is indeed a
gene, our 16C3 insertion P-element may inactivate it as it is
inserted within 30bp upstream of the predicted ATG, but that
insertion does not have a visible phenotype. We recovered three EMS
alleles that are lethal over the 16C3 mutation but that are viable
over two null moira alleles and are not mutated in RBF2 by
sequencing. However, the lethality is no longer larval and some
escapers occur when the EMS alleles are crossed to each other. These
might be EMS mutants of CG4287 called alleles F, K and R.
Best wishes,
Olivier Stevaux
\--