part_of part of part of has_part has part has part develops_from develops from develops from immediate transformation of brain midbrain hindbrain midbrain-hindbrain boundary isthmus/MHB mid-hindbrain junction midbrain hindbrain boundary isthmo-cerebellar region isthmic organizer territory The part of the brain that is the morphological boundary between the midbrain and hindbrain and that is the location of an organizing center which patterns the midbrain and hindbrain primordia of the neural plate. mid-hindbrain boundary MHB isthmus ectoderm-derived structure anatomical junction midbrain hindbrain boundary neural plate structure with developmental contribution from neural crest