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Ford, K. L.

Publications and source records attributed to Ford, K. L..

3 recordsLinked to original sources

Genomic innovation and horizontal gene transfer shaped plant colonization and biomass degradation strategies of a globally prevalent fungal pathogen

Members of the fungal genus Armillaria are necrotrophic pathogens with efficient plant biomass-degrading strategies. The genus includes some of the largest terrestrial organisms on Earth, spreading underground and causing tremendous losses in diverse ecosystems. Despite their global importance, the mechanism by which Armillaria evolved pathogenicity in a clade of dominantly non-pathogenic wood-degraders (Agaricales) remains elusive. Here, using new genomic data, we show that Armillaria species, in addition to widespread gene duplications and de novo gene origins, appear to have at least 775 genes that were acquired via 101 horizontal gene transfer (HGT) events, primarily from Ascomycota. Functional and expression data suggest that HGT might have affected plant biomass-degrading and virulence abilities of Armillaria, two pivotal traits in their lifestyle. We further assayed gene expression during root and cambium colonization, and report putative virulence factors, extensive regulation of horizontally acquired and wood-decay related genes as well as novel pathogenicity-induced small secreted proteins (PiSSPs). Two PiSSPs induced necrosis in live plants, suggesting they are potential virulence effectors conserved across Armillaria. Overall, this study details how evolution knitted together horizontally and vertically inherited genes in complex adaptive traits, such as plant biomass degradation and pathogenicity, paving the way for development of infection models for one of the most influential pathogens of temperate forest ecosystems.

genomics↗

A molecular mechanism for salt stress-induced microtubule array formation in Arabidopsis

Microtubules are filamentous structures necessary for cell division, motility and morphology, with dynamics critically regulated by microtubule-associated proteins (MAPs). We outline the molecular mechanism by which the MAP, COMPANION OF CELLULOSE SYNTHASE1 (CC1), controls microtubule bundling and dynamics to sustain plant growth under salt stress. CC1 contains an intrinsically disordered N-terminus that links microtubules at evenly distributed distances through four conserved hydrophobic regions. NMR analyses revealed that two neighboring residues in the first hydrophobic binding motif are crucial for the microtubule interaction, which we confirmed through live cell analyses. The microtubule-binding mechanism of CC1 is remarkably similar to that of the prominent neuropathology-related protein Tau, indicating evolutionary convergence of MAP functions across animal and plant cells.

cell biology↗

From Armament to Ornament: Performance Trade-Offs in the Sexual Weaponry of Neotropical Electric Fishes

The evolution of sexual weaponry is thought to have marked effects on the underlying static allometry that builds them. These weapons can negatively affect organismal survivability by creating trade-offs between trait size and performance. Here we use three-dimensional geometric morphometrics to study the static allometry of two species of sexually dimorphic electric fishes (Apteronotus rostratus and Compsaraia samueli) in which mature males grow elongate jaws used in agonistic male-male interactions. We quantify jaw mechanical advantage between the sexes of both species to track changes in velocity and force transmission associated with the development of sexual weaponry. We find evidence for trade-offs between skull shape and mechanical advantage in C. samueli, where males with longer faces exhibit lower mechanical advantages, suggesting weaker bite forces. In contrast, males, and females of A. rostratus exhibit no difference in mechanical advantage associated with facial elongation. We hypothesize that differences in the functionality of the sexual weaponry between the two species may drive divergences in the allometric scaling of mechanical advantage.

evolutionary biology↗