Subject: Re: FlyBase Query (cy360)
Dear Chihiro Yamada,
hopefully the answers enclosed will be helpful.
1. gro alleles.
These 5 alleles are described in
Preiss, A., D. Hartley and S. Artavanis-Tsakonas (1988).
The molecular genetics of Enhancer of split, a gene required for embryonic
neural development in Drosophila. EMBO J. 7: 3917-3928
In Lindsley and Zimm (1992), they were renamed r17 - r22, however, these
names are not commonly used in the literature.
All five are EMS induced alleles in an e4 tx background. They uncover the
recessive phenotype of gro1 and are lethal in trans and over deficiencies.
Therefore, they were named alleles of l(3) gro.
The mutations all affect the transcription unit m9/m10 in the E(spl)
region because they can be rescued with a respective trans-gene.
I am not aware that any of these alleles affect the neighboring
transcription unit E(spl) bHLH m8 and it seems rather unlikely because
they do not show any obvious molecular or cytological aberrations.
However, as long as there are no sequence data of these alleles available,
a double hit in m8 cannot be excluded. As far as I can tell, mutations in
m8 do not give any apparent phenotype. Therefore, a separation of
mutations in the two genes can only occur at the molecular level.
There is some confusion in naming the genes in the E(spl) region which is
based on the problems in their original characterization. Two 'historical'
alleles, gro and E(spl) have been name giving. E(spl) is a mutation in m8
which has little apparent phenotype on its own but enhances the eye
roughening of the recessive split allele of Notch in a dominant manner
(thus: E(spl)D). Revertants of E(spl)D were generated that are mostly
structural mutations (deletions and translocations) which affect several
genes in the region. Nearly all of them affect the neighboring gro gene
with exception of the three mutations mentioned in the paper. This is why
the name E(spl) was extended towards the whole region and the respective
genes that are further identified by their transcription unit label (m8 -
mdelta).
..
Best regards, Anette Preiss
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Prof. Dr. Anette Preiss
University of Hohenheim
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>
Subject: FlyBase Query (cy360)
Dear Dr Preiss,
I am currently curating your paper for FlyBase:
Nagel et al., 1999, Dev. Genet. 25(2): 168--179
I have a few questions I was hoping you could help me with.
1. gro alleles.
In your materials and methods section, you mention a number of gro
alleles: E28, E48, E73, E75, E105. Looking through our records, we
don't have all of these as alleles of gro, some of these appear as
alleles of m8. Are these all definitely alleles of gro? Are they
also alleles of m8? If they are alleles of both, are the gro and m8
phenotypes known to be separable? It is not clear from our records
what the situation is for these alleles and it would be very helpful if
you could help me sort this out.
..
Any information you give would be entered as a 'personal communication to FlyBase
from you to FlyBase, provided you are happy with that.
Thanks and Best wishes,
Chihiro
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Chihiro Yamada.
FlyBase (Cambridge),
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