Mutants are shifted to 29^oC at the time of microchaetae precursor determination (14-10 hours APF). Mutants differentiate a large number of extra microchaetes, phenotype is more severe in medial than lateral areas of the thorax. The mutant phenotype results from the development of an excess of neural precursors at the expense of epidermal cells. Clones generated during the first and second larval stages present a strong neurogenic phenotype and bristles along the border can be either wild type or mutant. Occasionally a mutant bristle can be found adjacent to a wild type one. Mutant cells are defective in both sending and receiving the lateral signal.

temperature-sensitive temperature of adult paralysis: 29^oC temperature of larval paralysis: 29^oC temperature causing developmental defects: 29^oC viability of allele over deficiency: very weak