Congruence patterns of aquatic communities in a tropical river basin, Malaysia

The loss of aquatic biodiversity in tropical streams of SE Asia is evident due to increasing anthropogenic activities. Therefore, there is a necessity for immediate and feasible conservation plans. Effective conservation planning depends on successful application of surrogate groups. However, progress of this approach is hindered by the paucity of relevant reports based on cross-taxon congruence analysis. In this study, we investigated congruence patterns among aquatic groups (Plecoptera, Trichoptera, Ephemeroptera, Odonata and fish) in six rivers located in the Kerian River Basin (KRB), Malaysia. Species richness was significantly correlated among aquatic groups (except for Ephemeroptera and Trichoptera where r = 0.040 and P = 0.202). The strongest relationship in species richness was reported between Ephemeroptera and Plecoptera. The Mantel's r coefficient of similarity matrices (based on the Bray-Curtis distance measure) showed a positive correlation between the matrices of Ephemeroptera-Trichoptera and Plecoptera-Trichoptera. However, a negative relationship was reported between Odonata-fish matrices. The relationships between average Trichoptera-Odonata distance to the centroid (i.e. beta diversity) among the aquatic groups were also investigated. The strongest relationship in the average to the centroids was reported between Ephemeroptera and Odonata (R2 = 0.424, P < 0.05). However, the weakest relationship was reported between Trichoptera and fish with R2 value of 0.024. It is concluded that richness of Plecoptera, Odonata and fish showed correlations patterns, and these can be used as surrogates for each other with some restrictions

Sensitivity and specificity of the antigen-based anterior nasal self-testing programme for detecting SARS-CoV-2 infection in schools, Austria, March 2021.

This study evaluates the performance of the antigen-based anterior nasal screening programme implemented in all Austrian schools to detect SARS-CoV-2 infections. We combined nationwide antigen-based screening data obtained in March 2021 from 5,370 schools (Grade 1-8) with an RT-qPCR-based prospective cohort study comprising a representative sample of 244 schools. Considering a range of assumptions, only a subset of infected individuals are detected with the programme (low to moderate sensitivity) and non-infected individuals mainly tested negative (very high specificity)

Developmental analysis and comparison of non-visual opsins in medaka and zebrafish

Für einen Organismus ist Licht ein sehr wichtiges Signal aus der Umwelt, das molekulare Prozesse und Verhalten beeinflusst. Diese Informationen werden von Photorezeptoren verarbeitet, welche von Opsinen kodiert werden. Sie werden in unterschiedliche Typen und Funktionen unterteilt, sind über den ganzen Körper verteilt und unterschiedliche Opsine werden oft gleich in mehreren Geweben exprimiert. Einer dieser Gruppen ist als TMT-Opsin bekannt. Diese sind nicht visuelle Ziliar-Opsine. Es wurde bereits Forschungsarbeiten publiziert, die sich auf diese Gruppe konzentrieren, mit einem speziellen Fokus auf tmt-opsin1b und tmt-opsin2 in Medakafischen. In dieser Arbeit hat man die Resultate dieser Forschung als Basis genommen und versucht, die Funktion von tmt-opsin1b und tmt-opsin2 noch klarer zu machen. Es konnte gezeigt werden, dass ein Knockout von diesen Opsinen zu keinen Entwicklungsproblemen oder -verzögerungen führt. Dadurch kann davon ausgegangen werden, dass eventuelle Entdeckungen in Knockout-Modellen einen Einfluss von dem gefragten Opsin zeigen, anstatt Nachwirkungen von Abweichungen in der Entwicklung. Weiters wurde gezeigt, dass der zuvor entdeckte Einfluss von tmt-opsin1b auf sst1b spezifisch ist. Hierbei wurde die Expression von Genen, welche mit sst1b co-lokalisieren, in tmt-opsin1b Mutanten analysiert. Um die Expression von Genen in Fischen besser visualisieren zu können, wurde versucht smFISH in Medaka zu etablieren. Zusätzlich wurden erste Versuche unternommen, das bisher gewonnenen Wissen von tmt-opsin1b in Medaka mit Zebrafischen zu vergleichen. Hierfür wurden Transkripte, welche unterschiedliche Regulationen in tmt-opsin1b Medakamutanten zeigen, hergenommen und deren Orthologe in Zebrafisch tmt-opsin1b Mutanten verglichen. Hier konnte gezeigt werden, dass einige dieser Gene spezifisch bei Medaka von tmt-opsin1b reguliert werden. Schlussends wurden die ersten Schritte zur Generation eines tmt-opsin2b Mutanten in Zebrafischen mithilfe von CRISPR/Cas9 unternommen.An important environmental cue for organisms is light, affecting molecular processes and their behavior. This information is processed by photoreceptors, which are encoded by opsins. In case of vertebrates, over a thousand different opsins have been found until today. Their types and functions are many, and alone in zebrafish over 40 different opsins have been found. These opsins are spread across the whole body, and many are expressed in more than one tissue. One group of these opsins are called TMT-Opsin, which are non-visual, ciliary type opsins. Research has already been done trying to characterize this group, with a special focus on tmt-opsin1b and tmt-opsin2 in medakafish. This work focusses on these findings and tries to elucidate the workings of tmt-opsin1b and tmtopsin2 further. It could be shown that a knockout of these opsins does not lead to any developmental problems, ensuring that any observed results in regards to tmt-opsins stems from the knockout of the opsin itself, and not due to any issues in development. Furthermore, to support findings showing that sst1b is regulated indirectly by tmt-opsin1b, transcripts co-localizing with these genes were identified. In course of this, it could be shown that the influence of tmt-opsin1b on sst1b is very specific. For better visualization of transcripts in fish brains, efforts were undertaken to establish smFISH protocol in medakafish and first results were achieved. Additionally, knowing that tmt-opsin1b affects certain transcripts in medaka, a cross-comparison in zebrafish was started. There, it could be shown that the regulation of some transcripts by tmt-opsin1b is specific to medaka. To go further with this comparison, a tmt-opsin2b knockout-model was designed in zebrafish with CRISPR/Cas9

TMT-Opsins differentially modulate medaka brain function in a context-dependent manner.

Vertebrate behavior is strongly influenced by light. Light receptors, encoded by functional opsin proteins, are present inside the vertebrate brain and peripheral tissues. This expression feature is present from fishes to human and appears to be particularly prominent in diurnal vertebrates. Despite their conserved widespread occurrence, the nonvisual functions of opsins are still largely enigmatic. This is even more apparent when considering the high number of opsins. Teleosts possess around 40 opsin genes, present from young developmental stages to adulthood. Many of these opsins have been shown to function as light receptors. This raises the question of whether this large number might mainly reflect functional redundancy or rather maximally enables teleosts to optimally use the complex light information present under water. We focus on tmt-opsin1b and tmt-opsin2, c-opsins with ancestral-type sequence features, conserved across several vertebrate phyla, expressed with partly similar expression in non-rod, non-cone, non-retinal-ganglion-cell brain tissues and with a similar spectral sensitivity. The characterization of the single mutants revealed age- and light-dependent behavioral changes, as well as an impact on the levels of the preprohormone sst1b and the voltage-gated sodium channel subunit scn12aa. The amount of daytime rest is affected independently of the eyes, pineal organ, and circadian clock in tmt-opsin1b mutants. We further focused on daytime behavior and the molecular changes in tmt-opsin1b/2 double mutants, and found that-despite their similar expression and spectral features-these opsins interact in part nonadditively. Specifically, double mutants complement molecular and behavioral phenotypes observed in single mutants in a partly age-dependent fashion. Our work provides a starting point to disentangle the highly complex interactions of vertebrate nonvisual opsins, suggesting that tmt-opsin-expressing cells together with other visual and nonvisual opsins provide detailed light information to the organism for behavioral fine-tuning. This work also provides a stepping stone to unravel how vertebrate species with conserved opsins, but living in different ecological niches, respond to similar light cues and how human-generated artificial light might impact on behavioral processes in natural environments