CONTROL OF NEURAL PRECURSOR SPECIFICATION BY PRONEURAL PROTEINS IN THE CNS OF DROSOPHILA

Formation of neural precursors in Drosophila is determined by proneura l genes. The distinctive pattern of expression of some genes of the ac haete-scute complex in the embryonic neuroectoderm has prompted the sp eculation that they could also function in the specification of neural precursor identity in the CNS. To test this hypothesis, we have analy sed the capacity of different proneural proteins to promote the develo pment of a particular CNS precursor, the MP2 precursor, Our results in dicate that: (i) all known proneural proteins are similarly able to su pport the formation of a neural precursor at the position of MP2; (ii) different proneural proteins promote the expression of different char acteristics of MP2; and (iii) a totally normal specification of the MP 2 fate can only be attained by the proneural genes achaete or scute.