Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
Record number 411969
Title A phylogenetic strategy based on a legume-specific whole genome duplication yields symbiotic cytokinin type-A Response Regulators
Author(s) Camp, R. Op den; Mita, S. De; Lillo, A.; Cao, Q.; Limpens, E.H.M.; Bisseling, T.; Geurts, R.
Source Plant Physiology 157 (2011)4. - ISSN 0032-0889 - p. 2013 - 2022.
Department(s) Laboratory of Molecular Biology
Publication type Refereed Article in a scientific journal
Publication year 2011
Keyword(s) lateral root-formation - nodule organogenesis - medicago-truncatula - lotus-japonicus - signal-transduction - diverse roles - white clover - gene family - arabidopsis - nodulation
Abstract Legumes host their rhizobium symbiont in novel root organs, called nodules. Nodules originate from differentiated root cortical cells that de-differentiate and subsequently form nodule primordia, a process controlled by cytokinin. A whole genome duplication (WGD) has occurred at the root of the legume Papilionoideae subfamily. We hypothesize that gene pairs originating from this duplication event and are conserved in distinct Papilionoideae lineages have evolved symbiotic functions. A phylogenetic strategy was applied to search for such gene pairs in order to identify novel regulators of nodulation, using the cytokinin phosphorelay pathway as a test case. In this way two paralogous type-A cytokinin Response Regulators were identified that are involved in root nodule symbiosis. MtRR9 and MtRR11 in Medicago truncatula, and an ortholog in Lotus japonicus, are rapidly induced upon rhizobium Nod factor signaling. Constitutive expression of MtRR9 results in arrested primordia that have emerged from cortical, endodermal and pericycle cells. In legumes lateral root primordia are not exclusively formed from pericycle cells, but also involves the root cortical cell layer. Therefore, the MtRR9 induced foci of cell divisions show a strong resemblance to lateral root primordia, suggesting an ancestral function of MtRR9 in this process. Together, these findings provide a proof of principle for the applied phylogenetic strategy to identify genes with a symbiotic function in legumes.
There are no comments yet. You can post the first one!
Post a comment
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.