Pod-2, along with pod-1, defines a new class of genes required for polarity in the early Caenorhabditis elegans embryo.
The asymmetric division of the one-cell Caenorhabditis elegans zygote gives rise to two cells of different size and fate, thereby establishing the animal's anterior--posterior (a-p) axis. Through genetics, a number of genes required for this polarity have been characterized, but many components remain unidentified. Recently, our laboratory discovered a mutation in the pod-1 gene (for polarity and osmotic defective) that uniquely perturbed polarity and osmotic protection. Here, we describe a new C. elegans polarity gene identified during screens for conditional embryonic lethals. Embryos in which this gene has been mutated show a loss of physical and developmental asymmetries in the one-cell embryo, including the mislocalization of PAR and POD-1 proteins required for early polarity. Furthermore, mutant embryos are osmotically sensitive, allowing us to designate this gene pod-2. Thus, pod-2, along with pod-1, defines a new class of C. elegans polarity genes. Genetic analyses indicate that pod-2 functions in the same pathway as pod-1. Temperature-shift studies indicate that pod-2 is required during oogenesis, indicating that aspects of embryonic polarization may precede fertilization. pod-2 mutant embryos also exhibit a unique germline inheritance defect in which germline identity localizes to the wrong spot in the one-cell embryo and is therefore inherited by the wrong cell at the four-cell stage. Our data suggest that pod-2 may be required to properly position an a-p polarity cue.
Tagawa
A
A
Division of Biology, Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, California 92093, USA.
Rappleye
C A
CA
Aroian
R V
RV
D000483:Alleles; D000818:Animals; D019521:Body Patterning / Q000235:genetics*; D017173:Caenorhabditis elegans / Q000196:embryology* / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins; D016764:Cell Polarity / Q000235:genetics; D005260:Female; D017238:Genes, Helminth; D008297:Male; D008840:Microfilament Proteins / Q000235:genetics*; D009154:Mutation; D009865:Oocytes / Q000166:cytology; D013696:Temperature
D029742:Caenorhabditis elegans Proteins; D008840:Microfilament Proteins; C401782:POD-1 protein, C elegans