Expression of Mmus\Gcm-rs1^Scer\UAS.cRa under the control of Scer\GAL4^sca-537.4 results in lethality. The extent of nerve cord condensation in these embryos is less than in age-matched wild-type embryos. Extra glial-like cells form at the expense of neurons in embryos expressing Mmus\Gcm-rs1^Scer\UAS.cRa under the control of Scer\GAL4^sca-537.4; there is a 60-80% reduction in the number of neurons per hemisegment and a similar increase in glial cells. The five neurons of the pentascolopidial lateral chordotonal organ (LCH5) are usually missing from abdominal segments, although they do occasionally form. Expression of Mmus\Gcm-rs1^Scer\UAS.cRa under the control of Scer\GAL4^arm.PS results in the formation of repo-expressing cells in the ectoderm which have the elongated and irregular shape typical of glial cells. The RP2 neurons are missing in 28% of hemisegments. The U/CQ neurons are occasionally missing and there is a minor reduction in the number of aCC/pCC neurons.