Male Neuronal Support Cells - Spicules

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The spicules are used by the male during mating to probe for the vulval opening and to hold the vulva open during ejaculation (<a href="#Liu1995">Liu and Sternberg, 1995</a>;<a href="#Garcia2001"> Garcia et al, 2001</a>).</p> <div align="center"><img src="images/MaleSpicFIG1.jpg" alt="MaleSpicFIG 1 The male copulatory spicules" name="MaleSpicFIG1" width="799" height="480" border="0" align="middle" class="Galborder" id="MaleSpicFIG1"><a name="MaleSpiccFIG1" id="MaleSpiccFIG1"></a></div> <span class="picturetitle"> MaleSpicFIG 1: The male copulatory spicules.</span><span class="style2"> <strong>A. </strong>SEM of male tail tip featuring the fan and spicules, ventral view. (Image source: SEM [Hall] 434 H07_5.)</span> <hr class="page-splits"> <div align="center"><img src="images/MaleSpicFIG2.jpg" alt="MaleSpicFIG 2 Epifluorescent images of the spicules" name="MaleSpicFIG2" width="775" height="296" border="0" align="middle" class="Galborder" id="MaleSpicFIG2"><a name="MaleSpicFIG2" id="MaleSpicFIG2"></a></div> <span class="picturetitle style2"> MaleSpicFIG 2: </span><span class="picturetitle">Epifluorescent images of the spicules.</span><span class="style2"><strong> A.</strong> Transgenic animals expressing the<em> cat-2::GFP</em> reporter gene a socket cell of the adult tail, lateral view. (Strain source: R. Lints and S.W. Emmons.) (Cell identification by L.I. Jiang and P.W. Sternberg.) <strong> B. </strong>Transgenic animals expressing the<em> unc-55::GFP</em> reporter gene, dorsal view. (Strain source: G. Shan and W.W. Walthall.) </span> <hr class="page-splits"> <div align="center"><img src="images/MaleSpicTABLE1.jpg" alt="MaleSpicTABLE 1 Summary of spicule cells" name="MaleSpicTABLE1" width="697" height="447" border="0" align="middle" class="Galborder" id="MaleSpicTABLE1"><a name="MaleSpicTABLE1" id="MaleSpicTABLE1"></a> </div> <span class="picturetitle"> MaleSpicTABLE 1: Summary of spicule cells. </span> <p>The left and right spicules each contain the dendrites of 2 sensory neurons, <a href="../../neurons/Individual Neurons/SPDframeset.html" target="_blank">SPDL/R</a> and <a href="../../neurons/Individual Neurons/SPVframeset.html" target="_blank">SPVL/R</a> (<a href="#MaleSpicFIG3">MaleSpicFIG 3</a>). The neuron processes are surrounded by spicule sheath cell (SPsh) syncytium which, in turn, is surrounded by spicule socket cell (SPso) syncytium (<a href="#MaleSpicFIG4">MaleSpicFIG 4</a>, <a href="#MaleSpicFIG6">MaleSpicFIG 6)</a>. The sheath syncytium is a fusion of two cells (SPshD/VL or SPshD/VR), the socket syncytium a fusion of 4 cells (SPso1-4L or SPso1-4R) (<a href="#MaleSpicFIG5">MaleSpicFIG 5</a>; <a href="#MaleSpicTABLE1">MaleSpicTABLE 1</a>). The socket cells secrete a cuticle that covers the outside of the spicule and is sclerotized (<a href="#Sulston1980">Sulston et al., 1980</a>; <a href="#Jiang1999">Jiang and Sternberg, 1999</a>). The sensory endings of the neurons are exposed at the spicule tip and so possibly sense chemosensory cues on the hermaphrodite surface during spicule prodding or in the hermaphrodite uterine environment during spicule insertion. The cell bodies of spicule neurons are located in the male-specific cloacal ganglia (L/R), which flank the proctodeum. SPsh and SPso cell bodies lie more anteriorly (<a href="#MaleSpicFIG3">MaleSpicFIG 3</a>; <a href="#MaleSpicFIG6">MaleSpicFIG 6</a>; <a href="#Sulston1980">Sulston et al., 1980</a><a href="http://www.wormatlas.org/ver1/Sulston%20postembmale_1980/toc.html" target="_blank"></a>).</p></td> </tr> <tr> <td align="left" background="#Chinsang2000" class="style1"> <div align="center"><br> <img src="images/MaleSpicFIG3.jpg" alt="MaleSpicFIG 3 Spicule neurons and epithelial cells" name="MaleSpicFIG3" width="636" height="350" border="0" align="middle" class="Galborder" id="MaleSpicFIG3"><a name="MaleSpicFIG3" id="MaleSpicFIG3"></a><span class="picturename"> </span></div> <span class="picturetitle"> MaleSpicFIG 3: Spicule neurons and epithelial cells. </span><span class="style2"> Illustration shows the adult male tail, featuring the spicules and related neurons, lateral view. (PAG) Pre-anal ganglion; (SPsh) spicule sheath cell; (SPso) spicule socket cell. </span> <hr class="page-splits"> <span class="picturetitle style2"><br> </span> <div align="center"> <img src="images/MaleSpicFIG4.jpg" alt="MaleSpicFIG 4 Internal views of late L4 male spicule" name="MaleSpicFIG4" width="686" height="416" border="0" align="middle" class="Galborder" id="MaleSpicFIG4"><a name="MaleSpicFIG4" id="MaleSpicFIG4"></a> </div> <span class="picturetitle"> MaleSpicFIG 4: Internal views of a late L4 male spicule. </span><span class="style2">Diagram showing longitudinal views of and L4 male spicule with transverse sections shown from 3 different places along the length. (AJ) Adherens junction; (SPsh) spicule sheath cell; (SPso) spicule socket cell. (Adapted from<a href="#Sulston1980"> Sulston et al., 1980</a>.)</span> <p>Spicules are also associated with a third pair of neurons, the sensory-motor neurons <a href="../../neurons/Individual Neurons/SPCframeset.html" target="_blank">SPCL/R</a> (<a href="#MaleSpicFIG3">MaleSpicFIG 3</a>). In contrast to <a href="../../neurons/Individual Neurons/SPDframeset.html" target="_blank">SPD</a> and <a href="../../neurons/Individual Neurons/SPVframeset.html" target="_blank">SPV </a>neurons, <a href="../../neurons/Individual Neurons/SPCframeset.html" target="_blank">SPCL/R</a> do not enter the spicules. They are attached to and innervate the protractor muscles that surround the spicules and control spicule movement (<a href="#MaleSpicFIG6">MaleSpicFIG 6B</a>, <a href="#MaleSpicFIG7A">MaleSpicFIG 7A</a>). The sensory endings of <a href="../../neurons/Individual Neurons/SPCframeset.html" target="_blank">SPCL/R</a><a href="http://www.wormatlas.org/ver1/neurons.htm/spc.htm" target="_blank"></a> are attached directly to the dorsal proctractor muscle via hemidesmosomes (Hd) (<a href="#MaleSpicFIG6">MaleSpicFIG 6B</a>). Their commissures form NMJs with dorsal and ventral protractors as they pass between them (<a href="#MaleSpicFIG7BC">MaleSpicFIG 7B</a>; <a href="http://www.wormatlas.org/ver1/Sulston%20postembmale_1980/toc.html" target="_blank">Sulston et al., 1980</a>; <a href="http://wormwiring.org/male/male.php" target="_blank">The Male Wiring Project</a>).<span class="style2"><br> </span> </p> <div align="center"> <img src="images/MaleSpicFIG5.jpg" alt="MaleSpicFIG 5 The sheath and socket syncytiums" name="MaleSpicFIG5" width="800" height="480" border="0" align="middle" class="Galborder" id="MaleSpicFIG5"><a name="MaleSpicFIG5" id="MaleSpicFIG5"></a> </div> <span class="picturetitle"> MaleSpicFIG 5: The sheath and socket syncytiums. </span><span class="style2"><strong>A.</strong> Low-power TEM showing the two spicule sensory neurons which are surrounded by the sheath cell syncytium which in turn is surrounded by the socket cell sycytium, transverse view. (Image source: N2Y LP [MRC] 77.)<strong> B.</strong> Higher magnification TEM of <em>white boxed </em>region in <strong>A</strong>, transverse view. <strong>C. </strong>Xloser view of the gap junction from the <em>white boxed </em>region in <strong>B</strong> (Image source: N2Y [MRC] 840R.) (PAG) Pre-anal ganglion; (LG[L/R]) lumbar gangia; (DRG) dorso-rectal ganglion; (N) nucleus; (GJ) gap junction. </span> <hr class="page-splits"> <div align="center"><img src="images/MaleSpicFIG6.jpg" alt="MaleSpicFIG 6 Ultrastructure of the spicule channel" name="MaleSpicFIG6" width="800" height="451" border="0" align="middle" usemap="#MaleIntroFIG6Map" class="Galborder" id="MaleSpicFIG6"><a name="MaleSpicFIG6" id="MaleSpicFIG6"></a> <span class="picturename"> </span></div> <span class="picturetitle"> MaleSpicFIG 6: Ultrastructure of the spicule channel. </span><span class="style2"><strong>A.</strong> Low-power TEM showing the spicule channel and its relationship with the spicule muscle cells, transverse view. (Image source: N2Y [MRC] 60.) <strong>B.</strong> Higher magnification TEM of <em>white boxed </em>region in <strong>A</strong>, transverse view. (Image source: N2Y [MRC] 984L.) (PAG) Pre-anal ganglion; (Hd) hemidesmosome. </span> <hr class="page-splits"></td> <tr> <td align="left" background="#Chinsang2000" class="style1"><p><span class="subtitle"><a name="Spiculeneuronconnectivity2" id="Spiculeneuronconnectivity2"></a></span><span class="style10"><br> 2 Spicule <strong> </strong>Neuron Connectivity </span></p> <p>Major synaptic targets of the spicule neurons include each other, hook and PCS neurons, the protractor muscles and the gonad (<a href="http://wormwiring.org/male/male.php" target="_blank">The Male Wiring Project</a><a href="http://worms.aecom.yu.edu/pages/male_wiring_project.htm" target="_blank"></a>). These connections emphasize that spicule behavior must be coordinated with the preceding step of vulval location and the subsequent step of sperm transfer (reviewed in <a href="http://www.wormbook.org/chapters/www_malematingbehavior/malematingbehavior.html" target="_blank"> WormBook: Male Mating Behavior - Barr and Garcia, 2006</a>). During mating the <a href="../hook/Hookframeset.html" target="_blank">hook</a> and <a href="../postcloacal/PCSframeset.html" target="_blank">PCS</a> detect the general location of the vulva and trigger spicule prodding behavior by inducing periodic contraction of the spicule proctractor muscles (<a href="#MaleSpicMOVIE1">MaleSpicMOVIE 1</a>). This stimulation appears to be indirect as neither hook nor PCS neurons synapse onto the muscles. <a href="../../neurons/Individual Neurons/SPCframeset.html" target="_blank">SPCL/R</a>, having both proprioceptive and motor connections with the proctractor muscles, register when the vulval slit is breached and induce tonic muscle contraction and full spicule insertion (<a href="#MaleSpicFIG6">MaleSpicFIG 6B</a>; <a href="#MaleSpicFIG7BC">MaleSpicFIG 7B</a>; <a href="#Garcia2001">Garcia et al, 2001</a>). Sensory neurons <a href="../../neurons/Individual Neurons/SPVframeset.html" target="_blank">SPVL/R</a> are required to inhibit premature ejaculation (<a href="#Liu1995">Liu and Sternberg, 1995</a>) but surprisingly do not have direct connections to the gonad. These neurons may therefore exert their effect through their connections with <a href="../../neurons/Individual Neurons/SPCframeset.html" target="_blank">SPCL/R</a> and the PCS neurons which innervate vas deferens and cloacal cells in the gonad-cloacal junctional region (<a href="#MaleSpicFIG7BC">MaleSpicFIG 7C</a>). <a href="../../neurons/Individual Neurons/SPDframeset.html" target="_blank">SPDL/R</a> connectivity are not known however they are the major targets of <a href="../../neurons/Individual Neurons/SPVframeset.html" target="_blank">SPVL/R</a>. </p> <div align="center"><a href="../../movies/Spicules.mp4"><img src="../../movies/Spicules.jpg" alt="MaleSpicMOVIE 1 Spicule muscle contraction" name="MaleSpicMOVIE1" width="450" height="214" border="0" align="middle" class="Galborder" id="MaleSpicMOVIE1"></a><a name="MaleSpicMOVIE1" id="MaleSpicMOVIE1"></a> </div> <span class="picturetitle"> MaleSpicMOVIE 1: Spicule muscle contraction. </span><span class="style2">Periodic vs Prolonged Spicule Muscle Contraction (Image source: L. Rene Garcia.) Click on image to play movie. </span> <hr class="page-splits"> <div align="center"><img src="images/MaleSpicFIG7A.jpg" alt="MaleSpicFIG 7A Spicule muscles" name="MaleSpicFIG7A" width="562" height="420" border="0" align="middle" class="Galborder" id="MaleSpicFIG7A"><a name="MaleSpicFIG7A" id="MaleSpicFIG7A"></a></div> <span class="picturetitle">MaleSpicFIG 7A: Spicule muscles. </span><span class="style2">Diagram of location of spicule muscles and <a href="../../neurons/Individual Neurons/SPCframeset.html" target="_blank">SPC</a> neuron, lateral view. (PAG) Pre-anal ganglion; (NMJ) neuromuscular junction.</span> <div align="center"><br> <img src="images/MaleSpicFIG7BC.jpg" alt="MaleSpicFIG 7B&C Synapses in the spicules" name="MaleSpicFIG7BC" width="800" height="343" border="0" align="middle" class="Galborder" id="MaleSpicFIG7BC"><a name="MaleSpicFIG7BC" id="MaleSpicFIG7BC"></a> </div> <span class="picturetitle">MaleSpicFIG 7B&C: Synapses in the spicules. </span><span class="style2"> <strong>B.</strong> TEM of region indicated in<strong> 7A </strong>showing synapse between SPC and protractor muscles, transverse view. (Image source: N2Y [MRC] 1221.) <strong>C.</strong> TEM of region indicated in<strong> 7A </strong>showing synapse between PCC and the vas deferens, transverse view. (Image source: N2Y [MRC] PAG 875.)</span> <hr class="page-splits"> <span class="subtitle"><a name="Spiculedevelopment3" id="Spiculedevelopment3"></a></span><span class="style10"><br> 3 Spicule <strong> </strong>Development</span> <p>All spicule cells, including spicule neurons, are derived from the <a href="http://www.wormbase.org/species/all/anatomy_term/WBbt:0003825" target="_blank">rectal cell B</a> which is present in the L1 of both sexes but is a blast cell only in the male (<a href="#MaleSpicFIG8">MaleSpicFIG 8</a>; <a href="#Sulston1977">Sulston and Horvitz, 1977</a>; <a href="#Sulston1980">Sulston et al., 1980</a><a href="http://www.wormatlas.org/ver1/Sulston%20postembmale_1980/toc.html" target="_blank"></a>). In males, B generates 47 progeny which form the cloaca and spicule channels that house the spicules, as well as the spicules themselves. Spicule development can be divided into 2 phases (1) spicule cell generation and (2) spicule morphogenesis.</p> <div align="center"><img src="images/MaleSpicFIG8.jpg" alt="MaleSpicFIG 8 Lineal origin of spicule cells" name="MaleSpicFIG8" width="549" height="693" border="0" align="middle" class="Galborder" id="MaleSpicFIG8"><a name="MaleSpicFIG8" id="MaleSpicFIG8"></a><span class="picturename"> </span></div> <span class="picturetitle">MaleSpicFIG 8: Lineal origin of spicule cells. </span><span class="style2"> **α vs β and γ vs δ fates determined by positional cues (see <a href="#MaleSpicFIG9">MaleSpicFIG 9</a>). Socket cells (SPso1-4L/R) of the L/R side fuse forming a 4-cell syncytium. Sheath cells (SPshD/V L/R) of the L/R side fuse forming a 2-cell syncytium (see <a href="#MaleSpicTABLE1">MaleSpicTABLE 1</a>). *Spicule neurons. (Adapted from <a href="#Sulston1980">Sulston et al., 1980</a>; <a href="#Chamberlin1994">Chamberlin and Sternberg, 1994</a>; <a href="#Jiang1999">Jiang and Sternberg, 1999</a>.)</span><br> <strong><a name="Spiculecellgeneration31" id="Spiculecellgeneration31"></a><span class="style13"><br> 3.1 Spicule cell generation</span></strong></p> <p>The <a href="../../images/BYUFlineages.jpg" target="_blank">B cell lineage</a> is defined by three distinct phases: early division, short range migrations and late divisions (<a href="#MaleSpicFIG8">MaleSpicFIG 8</a>). The early divisions begin in late L1 where the B cell divides asymmetrically to produce a large anterior daughter (<a href="http://www.wormbase.org/species/all/anatomy_term/WBbt:0006985" target="_blank">B.a</a>) and a small posterior daughter (<a href="http://www.wormbase.org/species/c_elegans/anatomy_term/WBbt:0006986" target="_blank">B.p</a>). This asymmetry is regulated by the <a href="http://www.wormbook.org/chapters/www_wntsignaling/wntsignaling.html#d0e2650">Wnt pathway</a> (a <a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00003029" target="_blank">LIN-44</a> /<a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00003006" target="_blank">LIN-17 </a>pathway; <a href="#Sternberg1988">Sternberg and Horvitz, 1988</a>; <a href="#Herman1994">Herman and Horvitz, 1994</a>). By mid-L2 B.a and B.p produce a total of 10 cells (<a href="#MaleSpicFIG8">MaleSpicFIG 8</a>, <a href="#MaleSpicFIG9">MaleSpicFIG 9</a>): B.a generates 4 cell pairs and B.p 1 pair. The 4 B.a-derived pairs migrate a short distance, arranging themselves in 2 rings of 4 cells around the developing cloaca. Among the aa and pp cells migration of the left and right cell is variable; either the left or right member can take the anterior position near the cloaca. Signals from neighboring cells of the <a href="../../images/BYUFlineages.jpg" target="_blank">F, U</a> (EGF <a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00002992" target="_blank">LIN-3</a>/ <a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00002299" target="_blank">LET-23</a> signaling) and <a href="../../images/BYUFlineages.jpg" target="_blank">Y </a>lineages (<a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00003004" target="_blank">LIN-15</a>) promote differences between these otherwise equivalent cells causing them adopt an anterior fate (for aa's = α, for pp's=γ) or a posterior fate (for aa's = β; for pp's= δ) (distinguished by the lineage produced in later cell divisions; <a href="#Chamberlin1993">Chamberlin and Sternberg, 1993</a>; <a href="#Chamberlin1994">1994</a>). Thus, the B lineage represents one of the few cases in <em>C. elegans</em> where cell fate is not fixed by lineal origin and is determined by environmental cues. Cells of the B.p lineage are patterned by <a href="http://www.wormbook.org/chapters/www_notchembryo/notchembryo.html" target="_blank">Notch signaling</a> (<a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00003001" target="_blank">LIN-12</a>) (<a href="#MaleSpicFIG8">MaleSpicFIG 8</a>; <a href="#Chamberlin1994">Chamberlin and Sternberg, 1994</a>). During L3, precursors α, β, ζ and γ generate the cells of the spicules.<br> </p> <div align="center"><img src="images/MaleSpicFIG9.jpg" alt="MaleSpicFIG 9 Spicule precursor cell fates" name="MaleSpicFIG9" width="543" height="763" border="0" align="middle" class="Galborder" id="MaleSpicFIG9"><a name="MaleSpicFIG9" id="MaleSpicFIG9"></a> </div> <span class="picturetitle">MaleSpicFIG 9: Spicule precursor cell fates. </span><span class="style2">Diagram depicting interaction between cells which specifys fates of spicule precursor cells. α, γ and ε are anterior fates; β, δ and ζ are posterior fates. (Based on <a href="#Chamberlin1994">Chamberlin and Sternberg, 1994</a>; <a href="#Emmons1997">Emmons and Sternberg, 1997</a>.)<br> </span><strong><a name="Spiculemorphogenesis32" id="Spiculemorphogenesis32"></a><span class="style13"><br> 3.2 Spicule morphogenesis </span></strong> </p> <p>The B cell lineage is complete by the L3/L4 molt. Spicule morphogenesis occurs during L4 and is part of a larger process of tail remodeling that begins at mid-L4 (38-40hrs, 20°C) and ends by the final molt (45hrs) (<a href="#MaleSpicFIG9">MaleSpicFIG 9</a>; <a href="#MaleSpicFIG10">MaleSpicFIG 10</a>; <a href="#MaleSpicFIG11">MaleSpicFIG 11</a>; <a href="#MaleSpicFIG12">MaleSpicFIG 12</a>); for tail remodeling see <a href="../hypodermis/MaleHypframeset.html" target="_blank">Epithelial System of the Male - Hypodermis</a>). In the adult, 2 pairs of proctodeal cells, Bε(l/r).pv (aka B.a(l/r)appv) and Bε(l/r).apa (B.a(l/r)apapa), lie immediately dorsal and ventral of the spicules and line the spicule channels (<a href="#MaleSpicFIG10">MaleSpicFIG 10</a>). These cells play a major role in establishing the characteristic elongated morphology of the spicules and the channel. During morphogenesis Bε(l/r).pv and Bε(l/r).apa migrate anteriorly, establishing cellular molds (spicule traces) into which future spicule cuticle is secreted (<a href="#MaleSpicFIG10">MaleSpicFIG 10</a>). Their migration is dependent on a TGF-β (<a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00000936" target="_blank">DBL-1</a>) signal, possibly coming from dorsal sex muscles (<a href="#Baird1999">Baird and Ellazar, 1999</a>). </p> <div align="center"><img src="images/MaleSpicFIG10.jpg" alt="MaleSpicFIG 10 Spicule morphogenesis" name="MaleSpicFIG10" width="785" height="629" border="0" align="middle" class="Galborder" id="MaleSpicFIG10"><a name="MaleSpicFIG10" id="MaleSpicFIG10"></a> </div> <span class="picturetitle">MaleSpicFIG 10: Spicule morphogenesis. </span><span class="style2"><strong>A.</strong> Diagram of spicule development, lateral view, medial left. Bε = B.a(l/r)ap. (dsr) Dorsal retractor muscle; (SPso) spicule socket cell. (Based on <a href="#Sulston1980">Sulston et al., 1980</a>; <a href="#Baird1999">Baird and Eliazar, 1999</a>.) <strong>B. </strong>Transverse view of boxed region in <strong>A. </strong>Bε(l).apa is not visible in this section. <strong>C. </strong> Normarski DIC image of the spicule trace. </span> <p>Bε(l/r).pv insert "fingers" into the dorsal spicule retractor (dsr) muscles (<a href="#MaleSpicFIG10">MaleSpicFIG 10</a>; see also <a href="../proctodeum/images/MaleProcFIG7.jpg" target="_blank">MaleProcFIG 7</a> in <a href="../proctodeum/Procframeset.html" target="_blank">Epithelial System of the male - Proctodeum</a>). The forward movement of retractors during tail morphogenesis likely facilitates spicule trace elongation. An FGF signal (<a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00001185" target="_blank">EGL-17</a>), expressed in the SPso cells (<a href="#MaleSpicFIG11">MaleSpicFIG 11</a>), has also been implicated in the process (<a href="#Jiang1999">Jiang and Sternberg, 1999</a>; reviewed in <a href="http://www.wormbook.org/chapters/www_maledevelopment/maledevelopment.html" target="_blank">WormBook: Male Development - Emmons</a>). The SPso cells are essential for spicule elongation and also for secretion of the spicule cuticle, which begins at ca. 42 hrs (<a href="#Jiang1999">Jiang and Sternberg, 1999</a><a href="http://www.wormbase.org/db/misc/paper?name=WBPaper00003579;class=Paper" target="_blank"></a>). Both spicule elongation and cuticle formation depend on the activity of heterochronic transcription factor <a href="http://www.wormbase.org/species/c_elegans/gene/WBGene00003015" target="_blank">LIN-29</a> which is expressed in <a href="../../images/BYUFlineages.jpg" target="_blank">B lineage</a> cells (<a href="#Euling1999">Euling et al., 1999</a>).</p> <div align="center"><img src="images/MaleSpicFIG11.jpg" alt="MaleSpicFIG 11 Spicule trace elongation" name="MaleSpicFIG11" width="800" height="209" border="0" align="middle" class="Galborder" id="MaleSpicFIG11"><a name="MaleSpicFIG11" id="MaleSpicFIG11"></a> </div> <span class="picturetitle">MaleSpicFIG 11: Spicule trace elongation. </span><span class="style2"><strong>A.</strong> Nomarski DIC image of late L4 male tail formation showing location of SPso cell body, lateral view, left sublateral plane. <strong>B.</strong> Transgenic animals expressing the<em> egl-17::GFP</em> reporter gene in male tail. (Strain source: R.D. Burdine and M.J. Stern.) (Cell identification by L.I. Jiang and P.W. Sternberg.) </span> <hr class="page-splits"> <div align="center"><img src="images/MaleSpicFIG12.jpg" alt="MaleSpicFIG 12 Ultrastructure of the developing spicule" name="MaleSpicFIG12" width="800" height="546" border="0" align="middle" class="Galborder" id="MaleSpicFIG12"><a name="MaleSpicFIG12" id="MaleSpicFIG12"></a> </div> <span class="picturetitle">MaleSpicFIG 12: Ultrastructure of the developing spicule. </span><span class="style2"><strong>A.</strong> TEM of late L4 stage male featuring the spicules, transverse view. <span class="style18">(Image source: JSG [MRC] 270.)</span></span> <span class="picturetitle style2">B. </span><span class="style18">Detailed view of boxed region in <strong>A </strong>featuring the adherens junctions (AJs) between the proctodeal cells and spicule processes. </span> <hr class="page-splits"> <span class="subtitle"><a name="References4" id="References4"></a></span><span class="style10"><br> 4 References</span> <p><a name="Baird1999"></a>Baird, S.E. and Ellazar, S.A. 1999. TGFbeta-like signaling and spicule development in <em>Caenorhabditis elegans</em>. Dev. Biol. <strong>212: </strong>93-100. <a href="http://dx.doi.org/10.1006/dbio.1999.9322" target="_blank">Article</a></p> <p><a name="Chamberlin1993"></a>Chamberlin, H.M. and Sternberg, P.W. 1993. Multiple cell interactions are required for fate specification during male spicule development in <em>Caenorhabditis elegans</em>. Development <strong>188: </strong>297-324. <a href="http://dev.biologists.org/cgi/reprint/118/2/297" target="_blank">Article</a> </p> <p><a name="Chamberlin1994" id="Chamberlin1994"></a>Chamberlin, H.M. and Sternberg, P.W. 1994. The <em>lin-3/let-23</em> pathway mediates inductive signalling during male spicule development in <em>Caenorhabditis elegans</em>. <strong>120: </strong>2713-21. <a href="http://dev.biologists.org/cgi/reprint/120/10/2713" target="_blank">Article</a></p> <p><a name="Emmons1997"></a>Emmons S.W. and Sternberg, P.W. 1997. Male Development and Mating Behavior. In <em>C. elegans II</em> (ed. D. L. Riddle et al.). Chapter 12. pp.295-334. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York.<a href="http://www.ncbi.nlm.nih.gov/books/NBK20073/" target="_blank"> Article</a></p> <p><a name="Euling1999"></a>Euling, S., Bettinger, J.C. and Rougvie, A.E. 1999. TGFbeta-like signaling and spicule development in <em>Caenorhabditis elegans</em>. Dev. Biol. <strong>206: </strong>142-56. <a href="http://linkinghub.elsevier.com/retrieve/pii/S0012-1606(99)99322-3" target="_blank">Article</a></p> <p><a name="Garcia2001"></a>Garcia, L.R., Mehta, P. and Sternberg, P.W. 2001. Regulation of distinct muscle behaviors controls the <em>C. elegans</em> male's copulatory spicules during mating. Cell <strong>107</strong>: 777-788. <a href="http://dx.doi.org/10.1016/S0092-8674(01)00600-6" target="_blank">Article</a></p> <p><a name="Herman1994"></a>Herman, M.A. and Horvitz, H.R. 1994. The <em>Caenorhabditis elegans</em> gene <em>lin-44</em> controls the polarity of asymmetric cell divisions. Development <strong>120: </strong>1035-47. <a href="http://dev.biologists.org/cgi/reprint/120/5/1035" target="_blank">Article</a> </p> <p><a name="Jiang1999"></a>Jiang, L.I. and Sternberg, P.W. 1999. Socket cells mediate spicule morphogenesis in <em>Caenorhabditis elegans</em> males. Dev. Biol. <strong>211: </strong>88-99. <a href="http://dx.doi.org/10.1006/dbio.1999.9293" target="_blank">Article</a></p> <p><a name="Liu1995"></a>Liu, K.S. and Sternberg, P.W. 1995. Sensory regulation of male mating behavior in <em>Caenorhabditis elegans</em>. Neuron <strong>14</strong>: 79-89. <a href="http://dx.doi.org/10.1016/0896-6273(95)90242-2" target="_blank">Article</a></p> <p><a name="Sternberg1988"></a>Sternberg, P.W. and Horvitz, H.R. 1988. <em>lin-17</em> mutations of<em> Caenorhabditis elegans</em> disrupt certain asymmetric cell divisions. Dev. Biol. <strong> 130: </strong>67-73. <a href="http://dx.doi.org/10.1016/0012-1606(88)90414-9" target="_blank">Abstract</a></p> <p><a name="Sulston1977"></a>Sulston, J.E. and Horvitz, H. R. 1977. Post-embryonic cell lineages of the nematode <em>Caenorhabditis elegans</em>. Dev. Biol. <strong>56</strong>: 110-156. <a href="http://www.wormatlas.org/ver1/postemblin_1977/toc.html" target="_blank">Article</a></p> <p><a name="Sulston1980"></a>Sulston, J.E., Albertson, D.G. and Thomson, J.N. 1980. The <em>Caenorhabditis elegans</em> male: Postembryonic development of nongonadal structures. Dev Biol. <strong>78</strong>: 542-576. <a href="http://www.wormatlas.org/ver1/Sulston postembmale_1980/toc.html" target="_blank">Article</a> </p> <p><a name="Sulston1983"></a>Sulston, J.E., Schierenberg, E., White J.G. and Thomson, J.N. 1983. The embryonic cell lineage of the nematode <em>Caenorhabditis elegans</em>. Dev. Biol. <strong>100</strong>: 64-119. <a href="../../ver1/Sulstonemblin_1983/toc.html" target="_blank">Article</a></p> <hr class="page-splits"></td> </tr><tr> <td align="left" class="style1"> <a href="#top"><img src="../../picts/topoff.gif" border="0" onMouseOver="this.src='../../picts/topon.gif'" onMouseOut="this.src='../../picts/topoff.gif'"> </a><br> This chapter should be cited as: Lints, R. and Hall, D.H. 2009. Male neuronal support cells, spicules. In<em> WormAtlas</em>.  doi:<a href="http://dx.doi.org/10.3908/wormatlas.2.11" target="_blank">10.3908/wormatlas.2.11</a><br> Edited for the web by Laura A. Herndon. 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