Fig. 1.

Isolation of embryonic chick placode-derived cranial sensory neurons by dissection and FACS. A Schematic of cranial sensory ganglia in embryonic day 12 (HH38) chick (adapted from [6]). The ganglia are labelled: trigeminal ganglion as two separate lobes (Top: ophthalmic; Tmm: maxillomandibular); vestibulo-acoustic ganglion (VA); epibranchial series as three separate ganglia (G: geniculate; P: petrosal; N: nodose). Also labelled are the neural crest-derived superior– jugular ganglionic complex (S/J); the inner ear (IE); and forebrain (FB); midbrain (MB) and hindbrain (HB) of the CNS. Colours indicate the sensory modality of ganglion: blue: general somatosensory; magenta: special somatosensory; green: viscerosensory. B Representative dissections of cranial sensory ganglia: Top, Tmm and VA at HH18, and P and N at HH23. C, D Representative FACS plots of cells stained for live/dead stain and NFM. C Control cell population: limb bud cells devoid of neurons, containing 50 % dead cells. D Petrosal ganglion cell population: 36 % of cells are NFM positive and dead cell marker negative