CENTRIOLE NUMBER AND PROCESS FORMATION IN ESTABLISHED NEURO-BLASTOMA CELLS AND PRIMARY DORSAL-ROOT GANGLION NEURONS

Abstract

EM on serial sections has been used to compare the number and position of centrioles and processes in 4 mouse neuroblastoma clones and in primary dorsal root ganglion neurons. Studies of Neuro-2a and NB41, and further experiments on N18 and N115 confirm that a sizeable percentage of the cells in all 4 neuroblastoma clones have multiple centrioles (2-12 per cell). No significant differences were seen between the number and arrangement of centrioles in the undifferentiated or differentiated states. Primary dorsal root ganglion neurons, although characterized by multiple processes, exhibit only 2 centrioles per cell, usually located as a pair on one side of the nucleus. The observation that both dorsal root ganglion neurons, and neuroblastoma cells with only 2 centrioles were capable of multiple process formation suggests that multiple centrioles are not obligatory for multiple process formation. No consistent relationship was seen between the location of the centrioles and the position of the processes casting further doubts on models which assume a direct relation between these characteristics.