Biology subjects

Smejkal, M.

Publications and source records attributed to Smejkal, M..

4 recordsLinked to original sources

bioRxiv2025

TMK interacting network of receptor like kinases for auxin canalization and beyond

Receptor-like kinases (RLKs), particularly the Transmembrane Kinase (TMK) family, play essential roles in signaling and development, with TMKs being key components of auxin perception and downstream phosphorylation events. While TMKs involvement in auxin canalization, a process essential for vasculature formation and regeneration, has been established, nonetheless, the additional signaling and regulatory partners remain poorly understood. In this study, we identify and characterize seven leucine-rich repeat RLKs (TINT1-TINT7) as novel interactors of TMK1, revealing their diverse evolutionary, structural, and functional characteristics. Our results show that TINTs interact with TMK1 and highlight their roles in regulating various developmental processes. Majority of TINTs contributes, together with TMK1, to auxin canalization, with TINT5 linking TMK1 to other canalization component CAMEL. Beyond canalization, we also establish the role of TINT-TMK1 interactions in processes such as stomatal movement and the hypocotyls gravitropic response. These findings suggest that TINTs, through their interaction with TMK1, are integral components of various signaling networks, contributing to both auxin canalization and broader plant development.

plant biology↗

bioRxiv2024

Hungry catfish - effect of prey availability on movement dynamics of a top predator

O_LIThe availability and spatial distribution of prey determines the energetic costs of predators foraging and largely drives their space use, activity level and foraging timing. Consequently, predators in ecosystems with different prey availability and distribution should adjust their movement patterns to optimise their foraging success in order to maximise efficiency. C_LIO_LIThe aim of this study was to investigate the ability of a top predator, European catfish (Silurus glanis), to adapt its space use, temporal activity and diet patterns in environments with varying prey density and distribution, and to examine the consequences for the catfishs body growth. C_LIO_LICatfish activity, tracked with high-resolution acoustic telemetry positioning systems deployed in two oligotrophic lakes with limited fish prey and one eutrophic reservoir with abundant fish prey, showed clear differences in their spatial and foraging behaviour. In oligotrophic, prey-poor lakes, catfish showed larger space use, altered diurnal activity patterns, reduced use of the open water, increased variability in inter- and intra-individual space use and had a more diverse diet compared to their conspecifics in the eutrophic, prey-rich reservoir. However, despite these behavioural alterations the reduced food availability in prey-poor lakes ultimately led to a reduced catfish growth, as these behavioural changes could not fully compensate for the lower prey fish abundance. C_LIO_LIThe study showed that top predators can combine different behavioural mechanisms and individual strategies to adapt to different ecological contexts. The observed ability of catfish to optimize activity, space use and diet highlights the evolutionary need to maximise foraging efficiency and overall fitness in different habitats, giving catfish a significant competitive advantage. Such competitive abilities are prerequisites for the actual catfish success as an invasive species within a Europe. C_LI

ecology↗

bioRxiv2023

First record of highly invasive Chinese sleeper Perccottus glenii Dybowski, 1877 (Perciformes: Odontobutidae) in the Elbe River Basin, Czechia

The Chinese sleeper (Perccottus glenii) has invaded European freshwaters and we present evidence of its first documented occurrence in the Elbe River basin in Czechia. The individual fish was caught by a fisherman and posted on social media. After immediately contacting the person in question, we obtained a live fish from him. The Chinese sleeper appears to have been present in interconnected ponds and streams for ten years and may have spread over a larger area. We recommend that eradication measures be implemented to prevent further spread. Statement of SignificanceThe Chinese sleeper has invaded many European countries in the last 50 years, and it is expected to invade western Europe because of the favourable conditions for its establishment. This finding indicates that it could spread in the Elbe River Basin, which could have serious impacts on floodplain and wetland ecosystems. To prevent this scenario, eradication measures should be implemented.

ecology↗

bioRxiv2021

Influence of internal seiche dynamics on vertical movement of fish

O_LIInternal seiches are common in stratified lakes, with significant effects on stratification patterns, hydrodynamics and vertical nutrient transport. In particular, seiche can change the vertical distribution of the thermocline and the cold hypolimnetic and warm epilimnetic water masses by several meters on a timescale of a few hours. The results are rapid and strong changes in temperature profiles and oxygen availability that can have profound effects on vagrant and sessile organisms. Internal seiche dynamics could therefore affect fish communities directly through physiological stress and elevated mortality, and indirectly through prey distribution. C_LIO_LIThe aim of this study was to analyze the effects of internal seiche dynamics on lacustrine fish behaviour, and to characterize fish reaction patterns, with the main focus on vertical movement of fish in the vicinity of a shifting thermocline, and avoidance of cold hypolimnetic water. C_LIO_LIThe analysis was based on acoustic telemetry data from Lake Milada, a post-mining lake in the Czech Republic, with a total of 55 tracked individuals of four species: northern pike (Esox lucius), wels catfish (Silurus glanis), tench (Tinca tinca) and rudd (Scardinius erythropthalmus). C_LIO_LIThe effects of seiche dynamics on the four species studied were weak but significant during the day, but only on rudd during the night. Upward seiche produced stronger reactions in fish than downward seiche, and the effects were manifested only during the strongest seiche events. C_LIO_LIThermocline shifting during seiche events may induce a transient reduction in habitat for seiche-reacting species, thus potentially affecting predation and other inter- and intra-specific interactions, and probably affecting fish community dynamics. C_LI Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

ecology↗