AVA
The Mind of 
	a Worm

Members: AVAL, AVAR.

AVA is a pair of interneurons with cell bodies situated in the lateral ganglia adjacent to the neuropile of the nerve ring. Processes from the cell bodies enter the nerve ring laterally and run round it, near the outside and posterior faces, to the contralateral side, eventually leaving the ring ventrally and entering the ventral cord. They then run the length of the cord positioned near the centre of the process bundle (figure 18), ending near the posterior extremity of the cord in the pre-anal ganglion. The processes of AVA are rather large and lightly staining (a); together with those of AVB they are the most prominent interneurons in the ventral cord. In the nerve ring they are exclusively postsynaptic and receive extensive synaptic input. The main presynaptic partners in this region are: SAA (*b), FLP (*a), RIC (*a), DVC (*c), PVP (*c), AUA (*c), ASH (*b), AQR (*c), ADL (*d), SDQ (*b), DVA (*c) and RIB (*g); there are gap junctions to RIM, URY and itself (a). In the ventral cord AVA is both pre- and postsynaptic, although the chemical synapses that it makes have rather few vesicles (b, c, d, e). The main synaptic output is to the ventral cord motoneurons: VAn (c), DAn (d), ASn (e) and also to PVC (b) and SAB. PVC (*g), VAn (*b), DAn (*c), ASn (*c) and SAB (*c) have gap junctions with AVA. There is considerable synaptic input from AVD (*a), AVE (*a) and AVB (*b) distributed along the length of the cord as well as some less extensive input from PVC (*f), ADE (*b) and PLM (*f). In the pre-anal ganglion, AVA receives synapses from PHB (*a), PQR (*g) and LUA (*a). Magnifications: (a-e) x 17000.


AVA ventral cord synapses (MoW Table Guide)
partners gap junctions synapses from synapses to and corecipients
PVC 10 3+11 m 7, 5LUA, 4PVC, 4DA8, 2PDE, VA10, DB5, VA4, DB3, DA7, DA5
VA11 8 - 6AS11, 3DA8, 2DA9, VA12, VA10, VD13
DA8 1 - 4PVC, 3VA11, 2AS11, VA12, DA7, DA9, VA10, VD13
DA4 5 - 3, 4DA3, 2DA5, 2VA3, VA4
VA10 2 - 1, 3AS10, 2DA7, PVC, VA11, AS11, DA8
DA5 5 - 2, 3V A5, 2DA4, PVC, DA6
DA3 2 - 2, 4DA4, 2DA2, VA3
AS11 - - 6VA11, 2DA8, VA10
DA7 2 - 2AVA, 2VA10, AS10, DA8, PVC
VA5 6 - 3DA5, V A6, AS6, DA6
LUA - 1 + 19 m 5PVC
DA9 - - 2, 2VA11, DA8
AS5 2 - 3VA6, AVB
DA1 8 - 2, AVA, SABD
AS10 1 - 3VA10, DA7
VA4 3 - PVC, DA4, AS4, DB3
DA2 3 - 1, 2DA3, AVE
VA6 5 - 3AS5, VA5
VA3 3 - 1, 2DA4, DA3
AVE - 8+30 m 2AS3, AS1, DA2
AVA 4 3m 2DA7, DA1
VA2 3 - 1, 2AS2
AS2 - - 1, 2VA2
AVD - 7 +56 m SABV, AS6
DB5 2 - 1, PVC
VA12 1 - DA8, VA11
SABV 4 - 1,AVD
AS6 2 - VA5, AVD
AS4 - - 1, VA4
VD13 - 2m DA8, VA11
DB3 - - PVC, VA4
DA6 - - DA5, VA5
PDE - - 2 PVC
AVB - 21+6 m 1, AS5
AS3 3 - 2AVE
SABD 4 - DA1
AS1 4 - AVE
PHB - 21 m -
PQR - 5 + 14 m -
FLP - 3+14m -
PLM - 1+4m -
PVN - 2+4m -
AVJ 2 2m -
PVD - 3m -
VD11 - 2 -
AVG - 1+1m -
VA7 5 - -
VA1 2 - -
VA5 1 - -
DA2 1 - -
VA8 1 - -
BDU - 2m -


Web adaptation, Thomas Boulin, for Wormatlas, 2001, 2002