AVK

AVKL, AVKR

Type: Interneuron
Connectivity:
- In MoW: AVK
- In WormWiring: AVKL_h, AVKR_h, AVKL_m, AVKR_m
- In Nemanode: AVK
In Wormbase: AVK, AVKL, AVKR
Lineage: AB plpapapap, AB prpapapap
Location: Ventral ganglion of head
Description: Unipolar ventral cord interneurons. The processes of each AVK neuron enter the nerve ring and cross the midline into the contralateral side. The processes then exit the nerve ring into the ventral cord where they extend to the preanal ganglion. The AVKR axon runs on the left side of the ventral cord while AVKL axon runs on the right side of the ventral cord. In males, AVKL has input from PDER and AVKR makes gap junctions to hypodermis and PVS (Jarrell et al., 2012).
Neurotransmitter/ Neuropeptide:
- FLP-1; FMRFamide-like peptide
(Nelson et al., 1998)
Innexin expression:
- INX-2
- INX-6
- INX-7
- INX-8
- INX-9
- INX-10a
- INX-12
- INX-14
- INX-18a
- INX-19
- UNC-7
- UNC-9
(Altun et al., 2009; Bhattacharya et al., 2019)

Receptor expression:
- GLR-5; glutamate receptor subunit
(Brockie et al., 2001)
Function:
- Regulates downstream SMB head motor neurons to modulate anterior bending (Ji et al., 2023)
- Mediates pathogen avoidance (Marquina-Solis et al., 2024)
Reporters:
- At CGC: MU1085 bwIs2 [flp-1::GFP + rol-6(su1006)]
- Other: ZX1834

Click pictures for higher resolution images and to play movie

IDENTIFICATION:

The three neurons, AIM, AIY and AVK resemble pearls-on-a-string, located posterior and slightly more superficial to the excretory cell nucleus on the right and left sides of the head. The nucleus of the excretory cell is the biggest one on the ventral side, below the terminal bulb of the pharynx and looks like an egg with a sunny-side-up appearance. The three neuronal nuclei can easily be located immediately posterior to the excretory cell nucleus, the most anterior one being AIM, the middle, AIY, and the most posterior one, AVK. On the right side, sometimes RIS nucleus accompanies these three nuclei.Cell and axon structures of AIY and AIM are very similar; care must be taken to differentiate between the two when identifying these two cells with fluorescent markers.

Click here for larger version
AVKL (AB plpapapap) development in the embryo. Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of AVKL; 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).

Click here for larger version
AVKR (AB prpapapap) development in the embryo. Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of AVKR; 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).

Last revision: September 12, 2025