Abstract
Root hairs of Legume plants carry unique feature in symbiosis with Rhizobia. Once root hair receives signals from its symbiont, the tip of the root hairs curls (Hac). However, nodulation minus mutants of Lotus japonicus lack complete Hac response to Nod factor signals. Therefore, the lack of distinct polarity at the tip of growing root hairs may result in deficiency of symbiosis. To investigate this hypothesis, we observed 4 different Nod- mutants. sym70 barely exhibit root hair responses, whereas other mutants of sym71, sym72, sym73 showed Had phenotype. We also performed actin staining for 4 mutants, showing different actin cytoskeleton pattern from a wild type. Moreover, sym72 could not reinitiate root hair growth after 2hrs of NF applications. These observations suggest that the factors affected in these 4 mutants may regulate re-direction of root hair cells after NF signal perception.
