part of fasciculates with develops from peptide hormone secreting cell MP1 precursor larval MP1 neuron FBbt:00001599 fly_anatomy.ontology VFB:FBbt_00001599 Interneuron residing slightly anterior and ventral to the posterior commissure in the corner formed by the connectives and the posterior commissure (Bossing and Technau, 1994). Its ipsilateral projection bifurcates in an anterior and posterior branch (which spans up to three neuromeres) that run within the medial sector of the connective. It is a peptidergic neurosecretory cell (Manning et al., 2012). midline precursor 1 cell MP1 tract larva neuron mesectodermal derivative larval neurosecretory neuron larval interneuron primary interneuron larval peptidergic neuron larval medial midline neuron