Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Subscribe

Logo for

Development 130 (19): 4553-4566

Modulation of EGF receptor-mediated vulva development by the heterotrimeric G-protein G{alpha}q and excitable cells in C. elegans

Nadeem Moghal1,*,{ddagger}, L. Rene Garcia2,*,{ddagger}, Liakot A. Khan3,{dagger}, Kouichi Iwasaki3, and Paul W. Sternberg1

1 Howard Hughes Medical Institute and Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
2 Department of Biology, Texas A&M University, 3258 TAMU, College Station, TX 77843, USA
3 Laboratory of Molecular Neurobiology, Neuroscience Research Institute AIST, Tsukuba, 305-8566, Japan



View larger version (114K):

[in a new window]
 
Fig. 1. Expression patterns of the regulatory elements contained in the aex-3 and myo-3 transgenic constructs. Left-hand images are Nomarski, and right-hand images are fluorescence. Scale bars: 20 µm. (A,B,G,H) Body-wall muscle. (C,D,I,J) Ventral cord neurons. (E,F,K,L) Vulval precursor cells. (A-F) Neuronal-specific expression of yfp from the aex-3 promoter in the presence of the last intron from egl-30. Animal is an early L3 stage hermaphrodite containing the pha-1(e2123ts) mutation, and rescued by the extrachromosomal array syEx570 [pha-1, aex-3::yfp::egl-30]. (B,F) Background fluorescence is from neuronally expressed YFP in other focal planes. (G-L) Muscle-specific expression of the egl-19 genomic coding region fused to gfp from the myo-3 promoter. Animal is an early L3 stage hermaphrodite containing the egl-19(n582) mutation and the extrachromosomal array syEx476 [myo-3::egl-19::gfp]. (J,L) Background fluorescence is from body-wall muscle-expressing GFP in other focal planes. AC, anchor cell.

 


View larger version (102K):

[in a new window]
 
Fig. 2. Expression pattern of the unc-18 promoter. Left-hand images are Nomarski, and right-hand images are fluorescence. Scale bars: 20 µm. Animals are pha-1(e2123ts) hermaphrodites at the early L3 stage, rescued by the extrachromosomal array syEx594 [pha-1, unc-18::yfp::egl-30]. (A,B) Head. (C,D) Tail. (E,F) Ventral cord. (G,H) Vulval precursor cells. (I,J) Body-wall muscle. Background fluorescence in H and J is from neuronal expression of the reporter. AC, anchor cell.

 


View larger version (146K):

[in a new window]
 
Fig. 3. Growth in a liquid environment promotes vulval induction. Scale bars: 20 µm. Animals are L4 stage hermaphrodites. (A) A wild-type animal displaying normal vulval induction that developed on standard NG plates. (B) A let-23(sy1) mutant animal displaying a vulvaless phenotype that developed on standard NG plates. (C) A let-23(sy1) mutant animal displaying normal vulval induction that developed in a liquid M9 environment.

 


View larger version (28K):

[in a new window]
 
Fig. 4. Depiction of vulval induction in the context of the whole animal. (A) A schematic transverse section through a developing hermaphrodite. The dorsal side of the worm is up. Dorsal and ventral nerve cord, blue circles labeled N; body-wall muscles in the four lateral quadrants, red cells labeled Mu; gonadal tissue, inverted U-shaped tissue; anchor cell, green circle labeled AC. Representative vulval precursor cell (grey cell labeled VPC). (B) One model for EGL-30 modulation of LET-23-mediated vulva development. Neurons (blue, N) are directly stimulated by environmental conditions and transduce a signal to muscle (red, Mu) via EGL-30, and possibly the UNC-13 and UNC-64 synaptic transmission proteins. Excitation of muscle by neuronally expressed (and possibly also by muscle-expressed) EGL-30 leads to activation of downstream components that include EGL-19 voltage-gated calcium channels. The muscle cells provide a modulatory signal that may upregulate BAR-1 activity in P6.p (grey cell, VPC) to cooperate with LIN-3 from the anchor cell (green, AC) to facilitate vulval induction. Hyp, hypodermis; Int, intestine.

 


To Advertise     Find Products


Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882