Behavioral genetics of caenorhabditis elegans unc-103-encoded erg-like K(+) channel. Academic Article uri icon

abstract

  • The Caenorhabditis elegans unc-103 gene encodes a potassium channel whose sequence is most similar to the ether-a-go-go related gene (erg) type of K+ channels. We find that the n 500 and e 1597 gain-of-function (gf) mutations in unc-103 cause reduced excitation in most muscles, while loss-of-function (lf) mutations cause mild muscle hyper-excitability. Both gf alleles change the same residue near the cytoplasmic end of S6, consistent with this region regulating channel activation. We also report additional dominant-negative and lf alleles of unc-103 that can antagonize or reduce the function of both gf and wild-type alleles. The unc-103 locus contains 6 promoter regions that express unc-103 in different combinations of body-wall and sex-specific muscles, motor-, inter- and sensory-neurons. Each promoter drives transcripts containing a unique first exon, conferring sequence variability to the N-terminus of the UNC-103 protein, while three splice variants introduce variability into the UNC-103 C-terminus. unc-103(0) hermaphrodites prematurely lay embryos that would normally be retained in the uterus and lay eggs under conditions that inhibit egg-laying behavior. In the egg-laying circuit, unc-103 is expressed in vulval muscles and the HSN neurons from different promoters. Supplying the proper UNC-103 isoform to the vulval muscles is sufficient to restore regulation to egg-laying behavior.

published proceedings

  • J Neurogenet

author list (cited authors)

  • Reiner, D. J., Weinshenker, D., Tian, H., Thomas, J. H., Nishiwaki, K., Miwa, J., ... Garcia, L. R.

complete list of authors

  • Reiner, David J||Weinshenker, David||Tian, Hong||Thomas, James H||Nishiwaki, Kiyoji||Miwa, Johji||Gruninger, Todd||Leboeuf, Brigitte||Garcia, L Rene

publication date

  • January 1, 2006 11:11 AM