VUM precursor FBbt:00001428 Midline precursor neuroblast of the ventral nerve cord located posteriorly to MP3 precursor and anteriorly to MNB neuroblast. It divides once, during embryonic development, to give rise to one motorneuron and one interneuron. There are 3 VUM precursors in each segment (MP4-6). VFB:FBbt_00001428 fly_anatomy.ontology embryonic ventral midline neuroblast