C. elegans morphogenesis is a complex process requiring numerous short-range migrations, rearrangements, and concerted cell movements. Several vab (variable abnormal) mutations have been identified, which disrupt essential morphogenic events, resulting in severe body deformities. We have isolated a novel vab mutation
vab-22 . The body morphology in
vab-22 mutants is variably abnormal in the region between posterior end of pharynx and vulva. In addition, morphologies of ventral and dorsal nerve cord, alae and muscle are also abnormal in this region. We examined the embryonic morphogenesis of
vab-22 embryos by using
jam-1::GFP . When wild-type embryos enclose the ventral hypodermis, their bodies rotate 90 o in the eggshells (termed as body rotation). In
vab-22(
km6) mutant embryos, the body rotation occurs at posterior regions but not at anterior regions, suggesting that
vab-22 is involved in the control of coordinated body rotation. We cloned the
vab-22 gene by SNP. The VAB-22 protein contains two zinc-finger like domains similar to the DNA-binding region of mammalian DRE-binding factor DREF. These results suggest that
vab-22 may regulate the transcription of components which participate in the embryonic body rotation.