We have identified
Conserved Non-
coding Elements (CNEs) in the regulatory region of
Caenorhabditis elegans and
Caenorhabditis briggsae mab-9, a T-box gene known to be important for
cell fate spe
cifi
cation in the developing
C. elegans hindgut. Two adja
cent CNEs (a region 78 bp in length) are both ne
cessary and suffi
cient to drive reporter gene expression in posterior hypodermal
cells. The failure of a genomi
c mab-9c="http://www.sciencedirect.com/scidirimg/entities/2237.gif" alt="two colons" title="two colons" border="0">gfp constru
ct la
cking this region to express in posterior hypodermis
correlates with the inability of this
constru
ct to
completely res
cue the
mab-9 mutant phenotype. Transgeni
c males
carrying this
constru
ct in a
mab-9 mutant ba
ckground exhibit tail abnormalities in
cluding morphogeneti
c defe
cts, altered tail autofluores
cen
ce and abnormal le
ctin-binding properties. Hermaphrodites display redu
ced sus
ceptibility to the
C. elegans pathogen
Microbacterium nematophilum. This
comparative genomi
cs approa
ch has therefore revealed a previously unknown role for
mab-9 in hypodermal fun
ction and we suggest that MAB-9 is required for the se
cretion and/or modifi
cation of posterior
cuti
cle.