The coordinated control of Ca2+ signaling is essential for development in eukaryotes. Cyclic nucleotide-gated channel (CNGC) family members mediate Ca2+ influx from cellular stores in plants1-4. Here we report the unusual genetic behavior of a quantitative gain-of-function CNGC mutation (brush) in Lotus japonicus resulting in a leaky tetrameric channel. brush resides in a cluster of redundant CNGCs encoding subunits which resemble metazoan voltage-gated potassium (Kv1-Kv4) channels in assembly and gating properties. Plants homozygous for brush are impaired in root development and infection by nitrogen-fixing rhizobia which segregated as a recessive monogenic trait. The brush allele exhibited quantitative behavior since overexpression of the cluster subunits was required to suppress the brush phenotype. The results reveal a mechanism by which quantitative competition between channel subunits for tetramer assembly can impact the phenotype of the mutation carrier.
- Kristina Haage
- Petra Dietrich
- Martin Parniske
- Martin Parniske
- David M Chiasson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Maria J Harrison, Boyce Thompson Institute for Plant Research, United States
© 2017, Chiasson et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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