Null Mutations in the lin-31 Gene Indicate Two Functions During Caenorhabditis elegans Vulval Development

• Published in: Genetics (Austin) 2000-12, Vol.156 (4), p.1595-1602
• Main Authors: Miller, Leilani M, Hess, Heather A, Doroquez, David B, Andrews, Noelle M
• Format: Article
• Language: English
• Subjects: Alleles; Amino Acid Sequence; Amino Acid Substitution; Animals; Binding Sites; Caenorhabditis elegans; Caenorhabditis elegans - embryology; Caenorhabditis elegans - genetics; Caenorhabditis elegans Proteins; Cellular biology; Codon, Nonsense; Deoxyribonucleic acid; Disorders of Sex Development; DNA; DNA Mutational Analysis; DNA, Helminth - genetics; DNA, Helminth - metabolism; DNA-Binding Proteins - genetics; DNA-Binding Proteins - physiology; Female; Genes; Genes, Helminth; Genetics; Helminth Proteins - genetics; Helminth Proteins - physiology; lin-31 gene; Male; Molecular Sequence Data; Morphogenesis; Multigene Family; Mutation; Mutation, Missense; Phenotype; Protein Structure, Tertiary; Sequence Alignment; Sequence Deletion; Sequence Homology, Amino Acid; Transcription Factors - genetics; Transcription Factors - physiology; Vulva - abnormalities; Vulva - cytology; Vulva - embryology; Worms
• ISSN: 0016-6731; 1943-2631; 1943-2631
• DOI: 10.1093/genetics/156.4.1595

The lin-31 gene is required for the proper specification of vulval cell fates in the nematode Caenorhabditis elegans and encodes a member of the winged-helix family of transcription factors. Members of this important family have been identified in many organisms and are known to bind specific DNA targets involved in a variety of developmental processes. DNA sequencing of 13 lin-31 alleles revealed six nonsense mutations and two missense mutations within the DNA-binding domain, plus three deletions, one transposon insertion, and one frameshift mutation that all cause large-scale disruptions in the gene. The missense mutations are amino acid substitutions in the DNA-binding domain and probably disrupt interactions of the LIN-31 transcription factor with its DNA target. In addition, detailed phenotypic analysis of all 19 alleles showed similar penetrance for several characteristics examined. From our analysis we conclude: (1) the null phenotype of lin-31 is the phenotype displayed by almost all of the existing alleles, (2) the DNA-binding domain plays a critical role in LIN-31 function, and (3) direct screens for multivulva and vulvaless mutants will probably yield only null (or strong) alleles of lin-31.