Worm Breeder's Gazette 15(2): 26 (February 1, 1998)

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

SET: Point Sept

Remi Terranova, Malek Djabali, Jonathan Ewbank

CIML, case 906, 13288 Marseille cedex 9, France.

     Hox genes specify cell fates in successive antero-posterior body
domains in vertebrates, insects and nematodes (1,2). Polycomb and
trithorax group genes are responsible for the initiation and maintenance
of Hox gene expression, as shown by their mutant phenotypes in
drosophila and mouse. Nematode homologues of these genes have been
discovered and their function is being studied in several labs. We are
interested in the function of a domain which is shared between trithorax
and polycomb members: the SET domain. This domain which is shared
between antagonistic proteins is very conserved and may play an
important role in the assembly of either transcriptional activating or
repressing protein complexes during development (3). In C. elegans, the
130 amino acid SET motif is present in MES-2, a protein similar to E(z)
(4). It is also present in T26A5.7 ('point sept' in French), which is
predicted to be a 288 residue protein.

     We have determined the expression pattern of T26A5.7 in worms
carrying a GFP reporter transgene. Early in development, T26A5.7 is
expressed in the majority of cells, its expression being more and more
restricted as development progress. The later expression pattern of
T26A5.7 is reminiscent of the expression pattern of the ensemble of
Hom-C genes (5). This change in the pattern with the GFP-fusion
construct is consistent with the variation of transcript levels during
development. To study further the function of this gene, we are looking
at the expression of the transgene in several other genetic backgrounds.
Also, in collaboration with D. Baillie  and N. O'Neil, we are currently
screening lethals that map to T26A5 in the hope of obtaining a strain in
which T26A5.7 is inactivated.

     Special thanks to J.-C. Labbe, A. Fire and T. Burglin.

1/ Kenyon C. (1994). Cell 78, 175-180
2/ Emmons S. W. (1996). Nature 382, 301-302
3/ Laible et al. (1997). EMBO J. 16, 3219-3232
4/ Holdeman R., Nehrt S., Strome S. (1996) Midwest Worm Meeting
5/ Wang et al., (1993). Cell 74, 29-42