Supplementary Materials Supplemental Data supp_24_2_810__index. arbuscular mycorrhizal fungi to host root cells. In addition, the GOF-CCaMK variants without the regulatory domains partly restore AMS but fail to support rhizobial contamination in mutants. These data show that AMS, the more ancient type of symbiosis, can be mainly regulated by the kinase activity of CCaMK, whereas RNS, which developed more recently, Dinaciclib distributor requires complex regulation performed by the regulatory domains of CCaMK. INTRODUCTION Legume plants benefit from two major mutualistic plantCmicrobe interactions: arbuscular mycorrhizal symbiosis (AMS) and root nodule symbiosis (RNS). AMS and RNS provide inorganic materials (mainly phosphate and nitrogen sources, respectively) to host plants. In return, the host herb supplies photosynthetic products to the symbionts and an anaerobic environment for RNS. These symbiotic nutrient materials have contributed to survival and fitness of the host plants on land. Arbuscular mycorrhizal (AM) fungi absorb inorganic materials and water from your rhizosphere through extraradical hyphae, which attach to and penetrate into the host root (Harrison, 2005). The intraradical hyphae elongate longitudinally in the apoplastic spaces between cortical cells, in which a tree-like symbiotic structure called the arbuscule is usually surrounded by the herb membrane (Bonfante and Perotto, 1995; Gianinazzi-Pearson, 1996). In the arbuscule, nutrients are exchanged across the fungal and herb membranes by transporters (Harrison and van Buuren, 1995; Bago et al., 2003). In RNS, the root nodule is usually a symbiotic secondary organ that evolves on the host roots for accommodation of the symbiont. Symbiotic partner rhizobia colonize root hairs and secrete rhizobial symbiosisCsignaling molecules called Nod factors (Lerouge et al., 1990; Dnari and Cullimore, 1993). Cortical cell division is usually stimulated by acknowledgement of Nod factors, resulting in nodule formation. The host herb takes rhizobia into the nodule cells through an contamination thread, a structure that allows bacterial access into the host roots (Gage, 2004). In the nodules, rhizobia produce nitrogenase to fix (convert) Rabbit Polyclonal to MOS atmospheric nitrogen into ammonia, which provides a usable nitrogen source for the host plants (Udvardi and Day, 1997). The host herb produces the oxygen Dinaciclib distributor binding protein leghemoglobin in the infected cells and maintains the anaerobic environment necessary for nitrogenase function. AMS and RNS share several similarities despite the differences between fungal and bacterial symbionts. These similarities have presumably originated from a common evolutionary origin. RNS, which is the more recent type of symbiosis, has retained some of the same symbiosis factors and mechanisms as the more ancient AMS type of symbiosis (Parniske, 2008; Markmann and Parniske, 2009). Indeed, previous studies have identified symbiosis mutants in legume plants that abolish both AMS and RNS. Several such symbiosis (((Tirichine et al., 2006). The kinase domain of the mutated CCaMK contains a Thr-to-Ile amino acid substitution at residue 265 (T265I), which is believed to mimic autophosphorylation for deregulation/activation of the CCaMK kinase domain. In mutants, deregulation of CCaMK appears to activate the RNS signaling pathway, which results in formation of a nodule-like structure called the spontaneous nodule (SPN) in the absence of rhizobia. Dinaciclib distributor In addition, another type of GOF-CCaMK has been identified in by truncation of the regulatory domains, resulting in similar phenotypes (Gleason et al., 2006). This indicates that the common Sym pathway is sufficient for activation of cortical cell division and consequent nodule formation in RNS (Hayashi et al., 2010; Madsen et al., 2010). However, the functions of GOF-CCaMK in AMS are largely unknown. Since AMS does not trigger obvious structural changes, such as nodule formation, induction of AMS-related genes can be used as a proxy to examine the functions of GOF-CCaMK in AMS. In and the phosphate transporter gene is induced by AM fungal infection (Takeda et al., 2009, 2011). Expression of is exclusively induced in AMS not in RNS, which is under the regulation of the common Sym pathway. RNA interference silencing of reduces hyphal Dinaciclib distributor elongation and arbuscule formation in the host roots (Takeda et al., 2009). Lj is an apparent Dinaciclib distributor ortholog of the Mt gene isolated from (Liu et al., 1998; Harrison et al., 2002; Guether et al., 2009). Mt is required for AMS, essential for maintenance of arbuscules in.