It is shown that rational dilation fails on broad collection of distinguished
varieties associated to constrained subalgebras of the disk algebra of the form
C + B A(D), where B is a finite Blaschke product with two or more zeros. This
is accomplished in part by finding a minimal set of test functions. In
addition, an Agler-Pick interpolation theorem is given and it is proved that
there exist Kaijser-Varopoulos style examples of non-contractive unital
representations where the generators are contractions.Comment: Page proof corrections included in this version

Annegret Kohler (44529)

Christophe Plomion (209802)

Delphine Vincent (2131087)

Emilie Solier (2131096)

Francis Martin (44535)

Johann Joets (193933)

Julien Gibon (2131090)

Marc-Henri Lebrun (44537)

Stephane Claverol (2131093)

English

arXiv

The ectomycorrhizal basidiomycete Laccaria bicolor has a dual lifestyle with a transitory soil saprotrophic phase and a longer mutualistic interaction with tree roots. Recent evidence suggests that secreted proteins play key roles in host plant colonisation and symbiosis development. However, a limited number of secreted proteins have been characterized, and the full spectrum of effectors involved in the mycobiont invasion and survival remains unknown. We analyzed the extracellular proteins secreted in growth medium by free-living mycelium of L. bicolor as a proxy for its saprotrophic phase. The proteomic analyses (two-dimensional electrophoresis and shotgun proteomics) were substantiated by whole-genome expression transcript profiling on ectomycorrhizal roots. Among the 224 proteins identified were carbohydrate-acting enzymes likely involved in the cell wall remodelling linked to hyphal growth as well as secreted proteases possibly digesting soil organic compounds and/or fending off competitors, pathogens, and predators. Evidence of gene expression was found in ectomycorrhizal roots for 210 of them. These findings provide the first global view of the secretome of a mutualistic symbiont and shed some light on the mechanisms controlling cell wall remodelling during the hyphal growth. They also revealed many novel putative secreted proteins of unknown function, including one mycorrhiza-induced small secreted protein

FigShare

Secretome of the Free-living Mycelium from the Ectomycorrhizal Basidiomycete Laccaria bicolor

https://figshare.com/articles/Secretome_of_the_Free_living_Mycelium_from_the_Ectomycorrhizal_Basidiomycete_i_Laccaria_bicolor_i_/2566078