Caenorhabditis elegans lin-25: cellular focus, protein expression and requirement for sur-2 during induction of vulval fates.
Induction of vulval fates in the C. elegans hermaphrodite is mediated by a signal transduction pathway involving Ras and MAP kinase. Previous genetic analysis has suggested that two potential targets of this pathway in the vulva precursor cells are two novel proteins, LIN-25 and SUR-2. In this report, we describe further studies of lin-25. The results of a genetic mosaic analysis together with those of experiments in which lin-25 was expressed under the control of an heterologous promoter suggest that the major focus of lin-25 during vulva induction is the vulva precursor cells themselves. We have generated antisera to LIN-25 and used these to analyse the pattern of protein expression. LIN-25 is present in all six precursor cells prior to and during vulva induction but later becomes restricted to cells of the vulval lineages. Mutations in genes in the Ras/MAP kinase pathway do not affect the pattern of expression but the accumulation of LIN-25 is reduced in the absence of sur-2. Overexpression of LIN-25 does not rescue sur-2 mutant defects suggesting that LIN-25 and SUR-2 may function together. LIN-25 is also expressed in the lateral hypodermis. Overexpression of LIN-25 disrupts lateral hypodermal cell fusion, suggesting that lin-25 may play a role in regulating cell fusions in C. elegans.
Nilsson
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L
Umeå Center for Molecular Pathogenesis, Umeå University, S-901 87 Umeå, Sweden.
Li
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X
Tiensuu
T
T
Auty
R
R
Greenwald
I
I
Tuck
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S
D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D012734:Disorders of Sex Development; D004627:Embryonic Induction; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D018507:Gene Expression Regulation, Developmental; D005838:Genotype; D015801:Helminth Proteins / Q000235:genetics*; D006720:Homozygote; D006358:Hot Temperature; D009030:Mosaicism; D011494:Protein Kinases / Q000235:genetics; D012045:Regulatory Sequences, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics* / Q000502:physiology; D014844:Vulva / Q000166:cytology / Q000196:embryology*
D029742:Caenorhabditis elegans Proteins; D004268:DNA-Binding Proteins; D015801:Helminth Proteins; C117637:LIN-25 protein, C elegans; C095846:Sur-2 protein, C elegans; D014157:Transcription Factors; D011494:Protein Kinases