Class 1 alleles (loss-of-function) n526n540ird : precocious heterochronic lineage alterations in ectoderm; abnormal development of vulva endoderm and mesoderm; abnormal cuticle formation; ES2; male more severely affected only three molts gonadal development abnormal. Similar phenotype in n536n540/Df. NA > 10 (n179ts etc.; also Class 1a n355n679ird ts (only early events precocious); Class 1b n360ts (only late events precocious). Class 2 alleles (gain-of-function) n536sd : retarded heterochronic alterations in many lineages abnormal vulval development cuticle formation supernumerary molts extra divisions in sex mesoblasts intestine etc.; gonadal lineages normal. ES3. ME0? NA2 (n355sd). For both Class 1 and Class 2 mutations late lineages are less affected if animal develops via dauer stage.
[C.elegansII] n526n540ird : lf allele (Class II, a-b-), precocious heterochronic lineage alterations in ectoderm; abnormal development of vulva,endoderm and mesoderm; abnormal cuticle formation; precocious dauer entry at L1 molt; ES2; male more severely affected, only three molts, gonadal development abnormal. Similar phenotype in n536n540/Df. OA>10: n179ts, etc.; also n355n679ird,ts (Class V, a-b+, only early events precocious); n360ts(Class III, a+b-, only late events precocious). Also gain-of-function alleles: n536sd (Class I, retarded heterochronic alterations in many lineages; abnormal vulval development, cuticle formation, supernumerary molts, extra divisions in sex mesoblasts, intestine etc.; gonadal lineages normal. ES3), n355sd(similar). Numerous intragenic revertants. For both lf and gf mutations, late lineages are less affected if animal develops via dauer stage. Cloned: two 3.5 kb transcripts, differing 5',encoding 70 kD novel proteins; antibodies stain nuclei; protein levels high in L1, reduced or absent later. Gain-of-function mutations affect3' UTR. [Ruvkun and Giusto 1989; Wightman et al. 1993; GR; VT]