Type: Interneuron
Connectivety:
- In MoW: AIB
- In WormWiring: AIBL_h, AIBR_h, AIBL_m, AIBR_m
- In Nemanode: AIB
In Wormbase: AIB, AIBL, AIBR
Lineage: AB plaapappa, AB praapappa
Location: Lateral ganglia in the head
Description: Amphid interneurons. The process of each AIB neuron travels through the amphid commissure to enter the ventral cord. From there, it travels anteriorly to enter the nerve ring. The process then runs dorsally and after making a brief anterior turn at the midline, it runs round the nerve ring. It reenters the ventral cord on the other side and ends within the ventral ganglion.
Neurotransmitter/ Neuropeptide:
- Glutamate
- FLP-20; FMRFamide-like neuropeptide
(Pereira et al., 2015; Li and Kim, 2008)
Innexin expression:
- INX-1
- INX-2
- INX-6 (only in dauer)
- INX-7
- INX-10a
- INX-18a
- UNC-7
- UNC-9
(Altun et al., 2009; Bhattacharya et al., 2019)

Receptor expression:
- GLR-1; glutamate-activated cation channel
- GLR-2; glutamate-activated cation channel
- Possibly GLR-5; kainate (non-NMDA)-type ionotropic glutamate receptor
- Possibly GGR-1; GABA-A/glycine receptor-like protein
- Possibly MGL-2; metabotropic glutamate receptor
(Wormbase; Fujiwara et al., 1996; Maricq et al., 1995; Brockie et al., 2001; Kang and Avery, 2009; O. Hobert, pers. comm.)
Function: Integration of information from amphid sensory neurons; AIBL/R is one of the four first layer amphid interneuron pairs (AIA, AIB, AIY, and AIZ) that receives and processes synaptic output from the amphid sensory neurons. AIA pair is suggested to sum inputs from various chemosensory neurons before passing the information on to AIB pair, which synapses onto motor neurons (AIA-AIB connections are likely to be inhibitory) (Wakayabashi et al., 2004).
- Functions in locomotion: Among the interneurons, AIA and AIY inhibit turns, AIB and RIA does not affect turning rates (Garrity et al., 2010; Wakayabashi et al., 2004).
- Functions in information processing within the AWC-AIB-AIY circuit that controls food- and odor-evoked behaviors (Chalasani et al., 2007). After animals are removed from bacterial food, they initiate a local search behavior consisting of reversals and deep omega-shaped turns. This is followed by dispersal ~30 min later, as reversals and turns are suppressed. Local search behavior is triggered by AWC olfactory neurons, ASK gustatory neurons, and AIB interneurons while dispersal is promoted by ASI gustatory neurons and AIY interneurons (Gray et al., 2005). AWC neurons are activated by odor removal and activate the AIB interneurons through AMPA-type glutamate receptors, while they inhibit AIY interneurons through glutamate-gated chloride channels; odor presentation relieves this inhibition and results in activation of AIY interneurons. The opposite regulation of AIY and AIB interneurons generates a coordinated behavioral response.
- Regulates lifespan and starvation response (starvation induces heat-shock resistance, oxidative stress resistance and extension of life-span). Certain amino acids (such as leu, gln, ala, val, ile) might act as signaling molecules that modulate the starvation response by acting as anti-hunger signals. The amino acid signal activates AIY neurons and inhibits AIB neurons by modulating the activities of MGL-1 and MGL-2 metabotropic glutamate receptors, respectively. AIY then inhibits the starvation response, whereas AIB activates it (Shen et al, 2010; Kang and Avery, 2009).
Reporters:
- At CGC:
- Other: ZQ281 lin-15B&lin-15A(n765) X; zwEx101[inx-1p::GFP + lin-15(+)] (Altun et al., 2009)