DHXT1, a Virulence Factor of Dactylellina haptotyla, Regulates Pathogenicity by Participating in Trap Formation and Metabolite Synthesis.

The capsule-associated protein 10 gene (CAP10) is indispensable due to its involvement in pod formation and virulence maintenance in Cryptococcus neoformans. The function of the CAP10 gene in nematode-predatory fungi remains unreported. As a typical nematode-trapping fungus, Dactylellina haptotyla efficiently captures nematodes using adhesive knobs, which has potential applications in the biological control of plant-parasitic nematodes. In this study, we investigated the function of DHXT1 (a CAP10 homologous protein) in D. haptotyla-nematode interactions based on the disruption and overexpression of DHXT1, phenotypic analysis and metabolomic analysis. As a result, it was shown that the disruption of the DHXT1 gene causes a marked decrease in the number of adhesive knobs, and on the contrary, the overexpression of the DHXT1 gene causes a substantial increase in the number of adhesive knobs. Interestingly, the variety of metabolites increased with the disruption of the DHXT1 and decreased with the overexpression of the DHXT1 gene. The results suggest that DHXT1 effects pathogenicity through its involvement in adhesive knobs' formation and metabolite synthesis and serves as a key virulence factor in D. haptotyla.

Improved small moving target detection method in infrared sequences under a rotational background.

The infrared image sequence contains both the rotational background and a moving target, causing great difficulties in target detection and the occurrence of massive false alarm rates. This paper proposes an improved method using an optical flow field, which can estimate and compensate for the rotational motion background, thus detecting a small moving target. First of all, we select the Shi-Tomasi angular points for image detection and represent the background rotation with the sparse optical flow field of a complete image. Then we use the least squares method to estimate the parameters of the perspective model of background rotation so as to reconstruct the background motion vector field and compensate for background rotation. Finally we detect the small moving target with the differential method and the morphological treatment. The experimental results verify that this method can accurately detect a small moving target against the violently rotational background and provide an idea for the target interception algorithm under the condition that an infrared imaging seeker is overlooking.