AVAL, AVAR

Type: Interneuron
In MoW: AVA
Male Wiring Project: AVAL, AVAR
In Wormbase: AVA, AVAL, AVAR
Lineage: AB alppaaapa, AB alaappapa
Location: Lateral ganglia of head
Description:
One of four bilaterally symmetric interneuron pairs (AVA, AVB, AVD, and PVC) with large-diameter axons that run the entire length of the ventral nerve cord and provide input to the ventral cord motor neurons. Synapse onto A-type (VA, DA) and AS motor neurons. Formerly called alpha. In males, AVAL receives input from PQR, PVY and PVX (Jarrell et al., 2012)
Neurotransmitter/ Neuropeptide:
- Acetylcholine
- FLP-1; FMRFamide-like peptide
- FLP-18; FMRFamide-related neuropeptide
(Although earlier reports suggested AVA might be glutamatergic, more recent studies showed it is not)
(Pereira et al., 2015; Serrano-Saiz et al., 2013; Ohnishi et al., 2011; Rogers et al., 2003; Nelson et al., 1998)

Innexin expression:
- INX-7
- UNC-7
- UNC-9
(Altun et al., 2009)
Receptor expression:
- Possibly GGR-3 ; GABA-A/glycine receptor-like protein
- GLR-1; glutamate receptor subunit
- GLR-2; glutamate receptor subunit
- GLR-4; glutamate receptor subunit
- GLR-5; glutamate receptor subunit
- NMR-1; glutamate receptor subunit
- NMR-2; glutamate receptor subunit




- UNC-8, a DEG/ENaC family member homologous to subunits of a candidate mechanically-gated, cation-specific ion channel
(Wormbase; Altun, 2011; Brockie et al., 2001; Tavernarakis et al., 1997; Fujiwara et al., 1996; Maricq et al., 1995)
Function: Command interneuron.
- Locomotion; functions as driver cell for backward locomotion (reversal). Drives backward movement of the animal along with touch modulator AVD neuron, AVE and A-type motor neurons. However, although AVA/AVD/AVE are important for initiating reversals, they are not essential, since worms lacking these neurons can still initiate reversals although at a reduced frequency (Piggott et al., 2011)


 
 

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AVAL (AB alppaaapa) development in the embryo.
Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of AVAL; dark grey spheres: apoptotic cells; other cells follow the WA color code (after they acquire specific cell or tissue identities). 0 min is fertilization. Click on the movie for higher resolution rendition (by A. Santella & Z. Bao).

 
 

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AVAR (AB alaappapa) development in the embryo.
Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of AVAR; dark grey spheres: apoptotic cells; other cells follow the WA color code (after they acquire specific cell or tissue identities). 0 min is fertilization. Click on the movie for higher resolution rendition (by A. Santella & Z. Bao).

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