sma-4 acts in a TGF-B signal transduction pathway affecting body size and male ray and spicule patterning.
sma-4 mutants are approximately 50% smaller than wildtype, have crumpled spicules and a characteristic transformation of ray 7 into ray 6, with an occassional transformation of ray 5 into ray 4. In characterizing
sma-4, we have found two distinct enhancer regions. One rescues only the body size (SMA) in a transformation rescue assay, and the other rescues both male tail phenotypes (MAB). The SMA enhancer has been narrowed down to a 1.5kb region, and we are in the process of narrowing down the MAB enhancer to a 100bp region. We are also looking at the expression patterns for each enhancer using gfp and lacZ expression vectors. This will give additional evidence that we have determined the location of each enhancer.