Subject: 'W3' confusion
Hi Rachel--
Enzo Munoz and I have been corresponding about a case of confusing
synonymy. I thought I'd summarize what we have figured out. Perhaps you
can archive this note in case someone tries to work on these genes and alleles.
There are two mutant strains called 'W3'. One of the mutated X chromosomes
carries mutations in the run and unc loci, and the other strain carries a
mutation in shakB. The relevant allele entries are
run9 FBal0014854
uncW3a FBal0095151
shakB15 FBal0015588
The W3 chromosome carrying run9 and uncW3a was described in Lifschytz
and Yakobovitz (Molec. Gen. Genet. 1978  161:275--284  = FBrf0032163). They
described recombination experiments that mapped lethality both to the left
of l(1)19Ec (=l(1)J9) and shakB (=l(1)R-9-29) and to the right of l(1)19Ec.
They also showed that the Dp(1;Y)mal+-linked lethal l(1)YT14 failed to
complement W3.
Lindsley and Zimm (DIS 68: 110, 1990) cite unpublished results of George
Lefevre, Jr. showing that 'l(1)W3b' is an allele of shakB. In this
reference l(1)W3b was called pas15. (Passover is a synonym for shaking
B.) In Lindsley and Zimm, 1992 (the Redbook), the synonym for shakB15
is l(1)N36, but I suspect 'N36' was simply a case of 'W3b' being written
down illegibly.
Enzo received both W3 lines from Lifschytz and maintained them as distinct
stocks. Crosses made by Abe Schalet and Enzo showed that the run9
uncW3a stock failed to complement run4 (=l(1)LB19), run2 (=l(1)AA33),
run18 (=l(1)17-26), run17-44, run19 (=l(1)17-169) and Df(1)16-3-53
for lethality and Df(1)17-351 for the unc phenotype, yet complemented
shakB6 (=l(1)E81), shakB11 (=l(1)R-9-29), shakB19 (=l(1)17-189) and
l(1)19Ec8 (=l(1)R-9-28).
Enzo worked less with the shakB15 stock, but nevertheless showed that it
failed to complement
shakB6 (=l(1)E81) and shakB11 (=l(1)R-9-29), yet complemented Df(1)17-351.
The distinction between the two W3 stocks must have been clear to Lifschytz
and Lefevre, because references to the run9 uncW3a chromosomes use
'W3a' in allele designations and references to the shakB15 chromosomes
use 'W3b'.
Nevertheless, the distinction was blurred in both Lindsley and Zimm 1990
and 1992, where l(1)YT14 was listed as an allele of shakB (=shakB17)
(presumably because both l(1)YT14 and shakB alleles failed to complement
something called 'W3'!). In Figure 2 of Lifschytz and Yakobovitz, 1978,
l(1)YT14 is shown mapping to the left of shakB, a position consistent with
it being an allele of run, rather than an allele of unc. This position of
l(1)YT14 was probably determined from complementation tests with deletions
to the left of shakB.
I recommend the following changes to FlyBase entries: (1) The shakB17
allele entry should be eliminated and a new allele entry created for
l(1)YT14 under the run gene--perhaps as runYT14. (The l(1)YT14
chromosome is extinct, so the purpose of this is to correct a historical
mistake and prevent confusion.) (2) l(1)W3 and l(1)W3b should be listed
as synonyms for shakB15.
Thanks!
Kevin