Conservation of Differential Animal MicroRNA Processing by Drosha and Dicer

In complex biochemical systems, an enzyme, protein, or RNA, symbolized as E, has hundreds or thousands of substrates or interacting partners. The relative specificity hypothesis proposes that such an E would differentially interact with and influence its many distinct, downstream substrates, thereby regulating the underlying biological process (es). The importance of relative specificity has been underappreciated, and evidence of its physiological consequences particularly lacking. Previously we showed that human Drosha and Dicer ribonucleases (RNases) both discriminate their respective microRNA (miRNA) substrates, and that differential cleavage by Drosha contributes to global differential miRNA expression. If relative specificity is an important biological mechanism, it should be evolutionarily conserved. To test this hypothesis, we hereby examined the cleavage of hundreds of zebrafish and fruitfly miRNA intermediates by Drosha and Dicer and the impact on miRNA biogenesis in these organisms. We showed that Drosha action regulates differential miRNA expression in zebrafish and fruitflies and identified the conserved secondary structure features and sequences in miRNA transcripts that control Drosha activity and miRNA expression. Our results established the conservation of miRNA processing mechanisms and regulatory functions by Drosha and Dicer, greatly strengthened the evidence for the physiological consequences of relative specificity as well as demonstrated its evolutionary significance.

Exploration of Medicinal Plants: Tinuktuk Concoction in Simalungunese, Indonesia

Plant species have been applied in the traditional treatment of certain diseases since ancient history. The purpose of this study is to explore the efficacy of medicinal plants, specifically tinuktuk, in Simalungunese, North Sumatra, Indonesia. This effort shows the potentials of local knowledge in preparing herbal mixtures, based on geographical existence. The sample concoction was analyzed qualitatively for its health properties, using a pragmatic approach. Subsequent data were obtained from focus group discussions and field demonstrations to determine the plant types, processing mechanisms and efficacy. The results showed that the leaves, stems, fruits, seeds, tubers, and rhizomes of 18 herbal plant varieties were utilized, alongside the evaluation of 8 medicinal properties. Among the species, Zingiberaceae, Arecaceae, and Euphorbiaceae belonged to genera, while Areacaceae, Poaceae, Rutaceae, and Zingiberaceae families were predominantly applied. Therefore, the efficacy determination of tinuktuk concoction appears significant in terms of facilitating lactation during childbirth and subsequently eliminating the unclean blood, enhancing immunity, maintaining stamina and increasing the appetite. In summary, the sample is suitable as a herbal medicine and a product of local knowledge in the treating various ailments across generations.

Motor imagery practice and feedback effects on functional connectivity

– Objective: the use of motor imagery (MI) in motor rehabilitation protocols has been increasingly investigated as a potential technique for enhancing traditional treatments, yielding better clinical outcomes. However, since MI performance can be challenging, practice is usually required. This demands appropriate training, actively engaging the MI-related brain areas, consequently enabling the user to properly benefit from it. The role of feedback is central for MI practice. Yet, assessing which underlying neural changes are feedback-specific or purely due to MI practice is still a challenging effort, mainly due to the difficulty in isolating their contributions. In this work, we aimed to assess functional connectivity (FC) changes following MI practice that are either extrinsic or specific to feedback. Approach: to achieve this, we investigated FC, using graph theory, in electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data, during MI performance and at resting-state (rs), respectively. Thirty healthy subjects were divided into three groups, receiving no feedback (control), “false” feedback (sham) or actual neurofeedback (active). Participants underwent 12 to 13 hands-MI EEG sessions and pre- and post-MI training fMRI exams. Main results: following MI practice, control participants presented significant increases in degree and in eigenvector centrality for occipital nodes at rs-fMRI scans, whereas sham-feedback produced similar effects, but to a lesser extent. Therefore, MI practice, by itself, seems to stimulate visual information processing mechanisms that become apparent during basal brain activity. Additionally, only the active group displayed decreases in inter-subject FC patterns, both during MI performance and at rs-fMRI. Significance: hence, actual neurofeedback impacted FC by disrupting common inter-subject patterns, suggesting that subject-specific neural plasticity mechanisms become important. Future studies should consider this when designing experimental NFBT protocols and analyses.

The Role of Multilingual Script Systems in Face Processing

Becoming multilingual has a broad impact on cognitive abilities, especially visual processing. An important theoretical issue is whether the acquisition of distinct script systems affects face processing in an identical way, or, if not, how this acquisition may exert differential impacts on face processing. By reviewing the existing literature, we propose that Asian participants with the logographic script system differ from Western counterparts with the alphabetic script system in viewing faces. The contribution of the chapter is to identify the possible role of types of script systems in face processing mechanisms and to put forward the research direction in the future with several new methodological efforts.

The Long TBLT Journey

In this piece, I trace Task-Based Language Teaching from Mike Long’s original conceptualization in 1985, through his development of methodological principles that are based on SLA theory and empirical evidence he gathered for three and half decades, to two recent (2010, 2015) practical examples of TBLT. Since there is still some important work to be done on remaining tricky issues, I highlight a few of these (unresolved in instructed SLA), such as sequencing according to complexity and the resilience of implicit processing mechanisms in adult language learning. In resolving these and other issues that will no doubt arise, I urge us all to follow Mike’s scrupulous lead in holding ourselves accountable to the empirical evidence.

The Processing Mechanisms of Two Types of Mixed Prospective Memory

Mixed prospective memory (MPM) needs to be executed when both external time and event cues appear. According to the clarity of time cues, MPM can be further divided into two types: time-point MPM and time-period MPM. There is no research on these two types of MPM. Whether existing theories of EBPM can explain its processing mechanisms is worth exploring. The current study was aimed at examining the differences in attentional allocation characteristics between these two types of MPM and EBPM under different difficult ongoing tasks. The results showed that the attention consumption of the two types of MPM groups was less than that of the EBPM group in the early and middle stages of high cognitive load, but there was no difference between the three groups in the later stage of the task. The attention distribution of time-point MPM and time-period MPM displayed dynamic changes: the time-point MPM only had attention consumption in the later stage, while the time-period MPM also existed in the early and middle stages. These results support dynamic multiprocess theory.

Genome-Wide Profiling Reveals Alternative Polyadenylation of Innate Immune-Related mRNA in Patients With COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has caused many deaths worldwide. To date, the mechanism of viral immune escape remains unclear, which is a great obstacle to developing effective clinical treatment. RNA processing mechanisms, including alternative polyadenylation (APA) and alternative splicing (AS), are crucial in the regulation of most human genes in many types of infectious diseases. Because the role of APA and AS in response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection remains unknown, we performed de novo identification of dynamic APA sites using a public dataset of human peripheral blood mononuclear cell (PBMC) RNA-Seq data in COVID-19 patients. We found that genes with APA were enriched in innate immunity -related gene ontology categories such as neutrophil activation, regulation of the MAPK cascade and cytokine production, response to interferon-gamma and the innate immune response. We also reported genome-wide AS events and enriched viral transcription-related categories upon SARS-CoV-2 infection. Interestingly, we found that APA events may give better predictions than AS in COVID-19 patients, suggesting that APA could act as a potential therapeutic target and novel biomarker in those patients. Our study is the first to annotate genes with APA and AS in COVID-19 patients and highlights the roles of APA variation in SARS-CoV-2 infection.

Exploration of Medicinal Plants: Tinuktuk Concoction in Simalungunese, Indonesia

Plant species have been applied in the traditional treatment of certain diseases since ancient history. The purpose of this study is to explore the efficacy of medicinal plants, specifically tinuktuk, in Simalungunese, North Sumatra, Indonesia. This effort shows the potentials of local knowledge in preparing herbal mixtures, based on geographical existence. The sample concoction was analyzed qualitatively for its health properties, using a pragmatic approach. Subsequent data were obtained from focus group discussions and field demonstrations to determine the plant types, processing mechanisms and efficacy. The results showed that the leaves, stems, fruits, seeds, tubers, and rhizomes of 18 herbal plant varieties were utilized, alongside the evaluation of 8 medicinal properties. Among the species, Zingiberaceae, Arecaceae, and Euphorbiaceae belonged to genera, while Areacaceae, Poaceae, Rutaceae, and Zingiberaceae families were predominantly applied. Therefore, the efficacy determination of tinuktuk concoction appears significant in terms of facilitating lactation during childbirth and subsequently eliminating the unclean blood, enhancing immunity, maintaining stamina and increasing the appetite. In summary, the sample is suitable as a herbal medicine and a product of local knowledge in the treating various ailments across generations.

Similar CNV Neurodynamic Patterns between Sub- and Supra-Second Time Perception

In the field of time psychology, the functional significance of the contingent negative variation (CNV) component in time perception and whether the processing mechanisms of sub- and supra-second are similar or different still remain unclear. In the present study, event-related potential (ERP) technology and classical temporal discrimination tasks were used to explore the neurodynamic patterns of sub- and supra-second time perception. In Experiment 1, the standard interval (SI) was fixed at 500 ms, and the comparison interval (CI) ranged from 200 ms to 800 ms. In Experiment 2, the SI was fixed at 2000 ms, and the CI ranged from 1400 ms to 2600 ms. Participants were required to judge whether the CI was longer or shorter than the SI. The ERP results showed similar CNV activity patterns in the two experiments. Specifically, CNV amplitude would be more negative when the CI was longer or closer to the memorized SI. CNV peak latency increased significantly until the CI reached the memorized SI. We propose that CNV amplitude might reflect the process of temporal comparison, and CNV peak latency might represent the process of temporal decision-making. To our knowledge, it is the first ERP task explicitly testing the two temporal scales, sub- and supra-second timing, in one study. Taken together, the present study reveals a similar functional significance of CNV between sub- and supra-second time perception.

Primary visual cortex straightens natural video trajectories

Many sensory-driven behaviors rely on predictions about future states of the environment. Visual input typically evolves along complex temporal trajectories that are difficult to extrapolate. We test the hypothesis that spatial processing mechanisms in the early visual system facilitate prediction by constructing neural representations that follow straighter temporal trajectories. We recorded V1 population activity in anesthetized macaques while presenting static frames taken from brief video clips, and developed a procedure to measure the curvature of the associated neural population trajectory. We found that V1 populations straighten naturally occurring image sequences, but entangle artificial sequences that contain unnatural temporal transformations. We show that these effects arise in part from computational mechanisms that underlie the stimulus selectivity of V1 cells. Together, our findings reveal that the early visual system uses a set of specialized computations to build representations that can support prediction in the natural environment.