The sperm-oocyte switch in the C. elegans hermaphrodite is controlled through steady-state levels of the fem-3 mRNA.
Post-transcriptional control regulates many aspects of germline development in the Caenorhabditis elegans hermaphrodite. This nematode switches from spermatogenesis to oogenesis and is, therefore, capable of self-fertilization. This sperm-oocyte switch requires 3' UTR-mediated repression of the fem-3 mRNA. Loss of fem-3 repression results in continuous spermatogenesis in hermaphrodites. Although several factors regulating fem-3 have been identified, little is known about the mechanisms that control fem-3. Here, we investigate the steady-state levels of the fem-3 transcript and the expression pattern of its protein product. We show that FEM-3 is exclusively present in germ cells that are committed to spermatogenesis. We found that in fem-3(gf)/+ heterozygotes, mutant fem-3 gain-of-function transcripts are more abundant than their wild-type counterpart. Furthermore, we show that the penetrance of the fem-3(gf) allele correlates with inefficient FBF binding and extended poly(A) tail size of fem-3 mRNAs. Finally, we show that wild-type and gain-of-function mutated fem-3 mRNAs associate equally well with polyribosomes. We propose that the fem-3 mRNA is regulated through stabilization rather than through translatability.
Department of Biology, University of Fribourg, CH-1700 Fribourg FR, Switzerland.
Simone
S
Zanetti
Sonja
S
Grinschgl
Marco
M
Meola
Marco
M
Belfiore
Samantha
S
Rey
Pamela
P
Bianchi
Alessandro
A
Puoti
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D029742:Caenorhabditis elegans Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D018507:Gene Expression Regulation, Developmental; D005812:Genes, Switch; D057850:Hermaphroditic Organisms / Q000235:genetics*; D006579:Heterozygote; D008297:Male; D009865:Oocytes / Q000254:growth & development*; D009866:Oogenesis / Q000235:genetics / Q000502:physiology; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D013091:Spermatogenesis / Q000235:genetics / Q000502:physiology; D013094:Spermatozoa / Q000254:growth & development*
D029742:Caenorhabditis elegans Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C075059:fem-3 protein, C elegans; C109286:fem-3-binding protein, C elegans