Program of the 2004 East Coast Worm Meeting - Caenorhabditis ...

21. mig-10 functions downstream of unc-6 and slt-1 to mediate axon guidance.
Christopher C. Quinn 1 , Elizabeth Stovall 2 , Elizabeth F. Ryder 2 , William G. Wadsworth 1
1Dept. of Pathology, Robert Wood Johnson Medical School, Piscataway, NJ
2Biology and Biotechnology, Worcester Polytechnic Institutute, Worcester, MA
Migrating axons are guided through the developing nervous system by extracellular guidance
cues. These cues interact with transmembrane receptors, causing an attractive or repulsive
response to the guidance cue. While many extracellular guidance cues and their receptors have
been identified, the intracellular mechanisms that mediate the response to the guidance cues are
largely unknown.
The ventral migrations of the AVM and PVM axons are guided by attraction to netrin/UNC-6
and repulsion from slit/SLT-1 (Gitai et al, 2002, Neuron 37,53-65; C.C.Q, unpublished
observations). We have found that MIG-10 is expressed in the AVM and PVM axons where it
functions cell-autonomously to mediate the axon’s response to both netrin/UNC-6 and slit/SLT-1.
This function occurs in parallel to UNC-34/enabled, a regulator of actin polymerization that acts
downstream of netrin/UNC-6 and slit/SLT-1 (Yu et al, 2002, Nat. Neurosci. 5, 1147-1154). MIG-10
is a cytoplasmic protein that includes several proline rich domains as well as a Ras Association
domain and a Plekstrin Homology domain. We propose that MIG-10 serves as a
signaling/adaptor protein that can integrate the repulsive and attractive guidance signals received
by these axons.