SIB

SIBDL, SIBDR, SIBVL, SIBVR

Type: Interneuron, (sublateral) motor neuron
Connectivity:
- In MoW: SIB
- In WormWiring: SIBDL_h, SIBDR_h, SIBVL_h, SIBVR_h, SIBDL_m, SIBDR_m, SIBVL_m, SIBVR_m
- In Nemanode: SIB
In Wormbase: SIB, SIBDL, SIBDR, SIBVL, SIBVR
Lineage: AB plppaaaaa, AB prppaaaaa,
AB plpapaapp, AB prpapaapp
Location: SIBV are in the ventral ganglion, while SIBD are in the lateral ganglia of the head
Description: SIB neurons extend their processes anteriorly into the nerve ring. These processes then exit the nerve ring posteriorly within the ventral or dorsal sublateral cords.
Neurotransmitter/Neuropeptide:
- Acetylcholine
(Although earlier reports suggested SIB might be glutamatergic, more recent studies showed it is not)
(Serrano-Saiz et al., 2013; Ohnishi et al., 2011;
Loer and Rand, 2022; Duerr et al., 2008; Rand and Nonet, 1997-Appendix 2)
Innexin expression:
- INX-1a
- INX-1b
- INX-2a
- INX-7
- INX-9
- INX-10a
- INX-12
- INX-14
- UNC-7
- UNC-9
(Bhattacharya et al., 2019; Altun et al., 2009)
Receptor expression:

Function:
- In wild type animals the NR is positioned around the center of the isthmus of the pharynx. CWN-2, the C. elegans Wnt5 homolog, and SIA and SIB neurons play an essential role in placement of the NR correctly in this position. CWN-2 is required at the time of nerve ring formation and functions through the Wnt receptor CAM-1. CWN-2 is a ligand for CAM-1 (Ror receptor) and CAM-1 expression in SIA and SIB neurons facilitates this function. When this pathway is perturbed the NR is displaced towards the anterior (Kennerdell et al., 2009).
Reporters:
- At CGC:
- Other:

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SIBDL(AB plppaaaaa) development in the embryo. Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of SIBDL; 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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SIBDR (AB prppaaaaa) development in the embryo. Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of SIBDR; 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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SIBVL (AB plpapaapp) development in the embryo. Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of SIBVL; 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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SIBVR (AB prpapaapp) development in the embryo. Dorsal view. Bottom is left side of the embryo. Spheres indicate individual nuclei. Black sphere: ancestors of SIBVR; 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: July 26, 2025