Type: Sensory neuron, motor neuron
Male Wiring Project: PCAL, PCAR
In Wormbase: PCA, PCAL, PCAR
Lineage: Y.plppd, Y.prppd
Location: L/R Cloacal ganglia
Description: One of 3 bilateral pairs of male specific sensory neurons (PCAL/R, PCBL/R, PCCL/R) that innervate the left and right post-cloacal sensilla (P.C.S.) in the male tail (Sulston et al., 1980). Unlike SPC, PCB and PCC, the PCA neurons do not make chemical synapses with the gonad (Jarrell et al., 2012; Male Wiring Project). However, similar to the PCB and PCC they have outputs onto the gubernacular erector (gec) and the oblique (aob, pob) muscle arms (see Male Wiring Project) and so may have motor as well as sensory function. PCAL/R have a cilium, a short striated rootlet and a basal body (Altun & Hall, unpub. observ., 2014; Sulston et al., 1980)
- Glu
(LeBoeuf et al., 2014)
Innexin expression:
Make gap junctions mainly to HOA and SPC. Less frequent gap junctions to each other, AVG, PVQ, PHA and PVX (see Male Wiring Project)
Receptor expression:
- The P.C.S. functions redundantly with the hook in several steps of male mating behavior: locating the vulva, promoting backing over the vulval region and inducing spicule prodding behavior which is used to precisely locate the vulval opening. P.C.S. neurons are responsible for coordinating the sensing of vulva position with spicule prodding; they sense vulva position using sensory processes that project posteriorly from the cloacal opening. They then stimulate oblique and gubernaculum muscles, which in turn, lead to twitch contractions in spicule protractors via gap junctions. The twitching in these muscles are transduced into prodding via hemidesmosome attachments between the protractor muscles and spicule cuticle. Once prodding leads to partial penetration, SPC neurons induce full insertion.
(LeBoeuf et al., 2014; Garcia et al., 2001; Liu and Sternberg, 1995; see Mating Movie)
- PCA neurons facilitate sperm release; ablation of PCB along with SPC decreases sperm ejaculation significantly. The remaining sperm release is likely due to PCA (LeBoeuf et al., 2014)


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