Subject: Re: spdo/tmod split
Dear David,
(Hugo \- I agreed with everything you wrote but felt I should copy you anyway)
>Dear Hugo and James,
>
>I'm currently engaged in the tricky task of trying to split FlyBase's current
>record for spdo into 2 (tmod/CG1539 & spdo/CG31020), based on the data in
>'O'Connor-Giles and Skeath, 2003, Dev. Cell 5(2): 231--243'.
>
>I'd like to check with you that my proposed partitioning of the alleles fits
>with your understanding of their behaviour. Any additional complementation or
>molecular data that could help with this partitioning would be most welcome. I
>can curate such data as a personal communication to FlyBase.
>
>The tough question is what to do with 'spdoH7'(*) and its associated data.
>
> On the basis of the mapped insertion 'P{lacW}spdoH7' (now to be renamed
>P{lacW}tmod)H7) it needs to be an allele of tmod. On the basis of
>failure to
>complement spdoC55 (see below), it needs to be an allele of spdo. The most
>obvious explanation is that the 'H7' chromosome has mutations in both genes \-
>suggesting I should make both alleles. This still leaves the problem of where
>to put the phenotypic data.
>
>Any suggestions?
I agree with Hugo. It most likely hits two or more genes. The only
anecdotal light I may be able to shed is that Kate thought it might
be a deletion \- as when she performed plasmid rescue the right rescue
was always from tmod and the left rescue was from the original P
insert. spdo is found between these two genes.
As for phenotype, our lab does not know the phenotype of tmod either.
The asymmetric division phenotype appears to arise from a defect in
spdo. But, the phenotype of tmod is unclear to me.
>Here is how I plan to split the rest of the alleles between the two genes:
>
>Alleles remaining spdo/CG31020:
>
>1. lesions mapped by O'Conner-Giles & Skeath:
>
>spdoC55
>spdoG104
>spdoK433
>
>spdoZZ27 (a deficiency removing spdo/CG31020 : data from FBrf0162056 ==
>O'Connor-Giles and Skeath, 2003, Dev. Cell)
> Strictly we only make alleles from Dfs when one of their
>breakpoints is in the
>gene in question \- Is this the case?
We have not mapped the endpts of the df. But, I am fairly that
neither of the bkpts is in spdo \- rather spdo is completely contained
within the deficiency.
>2. On the basis of complementation:
>
>spdoS097002b
>Separable from: P{lacW}S097002a
>data from: FBrf0099763 Salzberg et al., 1997:
>Fails to complement: spdoC55
>Southern analysis reveals a chromosomal rearrangement.
>Lethality not revertible by Δ2-3-induced mobilization
>
>Fails to complement: spdoC55
>Isolation of spdoH7 by failure to complement spdoC55 is described in
>'Dye et al., '98 FBrf0102830'
>
>Alleles to split out as tmod:
>1. constructs:
>spdohs.PDL is the only one of these
>'rescue' data for 'spdoH7' \- should this now be recorded as partial
>suppression of a spdoH7 phenotype by hs-tmod?
>
>2. Insertions mapped to CG1539:
>
>spdo02288
>spdo00848
>
>3. Leision mapped to CG1539
>
>spdoS130910
>A portion of the CG1539 gene is deleted. (data Dye et al., '98 FBrf0102830)
>
>spdoZZ27 (a deficiency removing tmod/CG1539: data from FBrf0162056 ==
>O'Connor-Giles and Skeath, 2003, Dev. Cell)
> Strictly we only make alleles from Dfs when one of their
>breakpoints is in the
>gene in question \- Is this the case?
see above.
>
>4. On basis of complementation only:
>
>spdorG347
>Fails to complement: spdo00848
>(data from BDGP)
>
>Thanks in advance
I concur with what Hugo said about the origin of the confusion on this stuff.
The only thing potentially to add is that we have identified the
molecular lesion for a number of other spdo alleles. These data are
in the Dev Cell paper \- if Flybase is interested in adding them to
the listing.
take care,
Jim