Multiple roles for the E/Daughterless ortholog HLH-2 during C. elegans gonadogenesis.
HLH-2 is the Caenorhabditis elegans ortholog of the Drosophila Daughterless and mammalian E basic helix-loop-helix (bHLH) transcriptional activators that function during diverse events during animal development. HLH-2 has been implicated in cell fate specification in different neural lineages and in the LIN-12/Notch-mediated anchor cell (AC)/ventral uterine precursor cell (VU) decision in the somatic gonad. Here, we show that hlh-2 plays several distinct roles during somatic gonadogenesis. Our analysis suggests that hlh-2 is required to endow specific somatic gonadal cells with the competence to undergo the AC/VU decision, as well as functioning in the AC/VU decision per se; this novel "proAC" role appears to be analogous to the proneural role of Drosophila Daughterless. In addition to its two distinct roles in the specification of the AC, hlh-2 is also required for correct differentiation and function of the AC. hlh-2 also acts at an independent point in the gonadal lineage both to specify distal tip cells (DTCs) and in DTC differentiation and function.
Karp
Xantha
X
Department of Genetics and Development, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA. xek1@columbia.edu
Greenwald
Iva
I
D000818:Animals; D030801:Animals, Genetically Modified; D051792:Basic Helix-Loop-Helix Proteins; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics; D029742:Caenorhabditis elegans Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002454:Cell Differentiation / Q000235:genetics; D019070:Cell Lineage; D004268:DNA-Binding Proteins / Q000502:physiology; D012734:Disorders of Sex Development / Q000235:genetics; D029721:Drosophila Proteins / Q000502:physiology; D004625:Embryo, Nonmammalian; D005260:Female; D018507:Gene Expression Regulation, Developmental; D007814:Larva; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D038081:Organogenesis / Q000502:physiology*; D034622:RNA Interference; D051880:Receptors, Notch; D014157:Transcription Factors / Q000502:physiology*; D014599:Uterus / Q000002:abnormalities / Q000166:cytology / Q000196:embryology*
D051792:Basic Helix-Loop-Helix Proteins; D029742:Caenorhabditis elegans Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D008565:Membrane Proteins; D051880:Receptors, Notch; D014157:Transcription Factors; C090080:Da protein, Drosophila; C106514:HLH-2 protein, C elegans; C082460:Lin-12 protein, C elegans; C086488:lag-2 protein, C elegans