An epigenetic change is a heritable genetic alteration that does not involve any nucleotide changes. While the methylation of specific DNA regions such as CpG islands or histone modifications, including acetylation or methylation, have been investigated in detail, the role of small RNAs in epigenetic regulation is largely unknown. Among the many types of small RNAs, tRNA-derived small RNAs (tsRNAs) represent a class of noncoding small RNAs with multiple roles in diverse physiological processes, including neovascularization, sperm maturation, immune modulation, and stress response. Regarding these roles, several pioneering studies have revealed that dysregulated tsRNAs are associated with human diseases, such as systemic lupus, neurological disorder, metabolic disorder, and cancer. Moreover, recent findings suggest that tsRNAs regulate the expression of critical genes linked with these diseases by a variety of mechanisms, including epigenetic regulation. In this review, we will describe different classes of tsRNAs based on their biogenesis and will focus on their role in epigenetic regulation.

The use of group drawing to promote student-generated representation is a common instructional strategy as it combines the benefits of using visual representation and collaborative talk. Although the affordances of group drawing have increasingly been emphasized in science education, few studies have investigated how drawing as a How to cite this article:

The purpose of this study is to investigate the process of students' construction of scientific explanations through drawing explanatory diagrams. For this, we observed fifth and sixth graders' drawing processes in a gifted science class involving learning physics concepts in mechanics. The analysis was carried out on three pictorial representational levels: sensory (e.g., observed materials), unseen substance (e.g., molecules) and unseen non-substance (e.g., forces). We found that there were five patterns of interplay depending on the sequential path through the pictorial representational levels. All students began drawing explanatory diagrams from the sensory level as the first step and then constructed explanations using the unseen levels based on the interplay among different levels. In the process of forming meaningful relationships among the three levels of representation, students focused on a specific phenomenon through drawing at a sensory level and extended their making sense of the phenomenon from what happened to why it happened. Based on these findings, we suggest how teachers can use the interplay among the different pictorial representational levels to guide students in generating scientific explanations through drawing.

This paper argues that meaning-making with multimodal representations in science learning is always contextualized within a genre and, conversely, what constitutes an ongoing genre also depends on a multimodal coordination of speech, gesture, diagrams, symbols, and material objects. In social semiotics, a genre is a culturally evolved way of doing things with language (including non-verbal representations). Genre provides a useful lens to understand how a community’s cultural norms and practices shape the use of language in various human activities. Despite this understanding, researchers have seldom considered the role of scientific genres (e.g., experimental account, information report, explanation) to understand how students in science classrooms make meanings as they use and construct multimodal representations. This study is based on an enactment of a drawing-to-learn approach in a primary school classroom in Australia, with data generated from classroom videos and students’ artifacts. Using multimodal discourse analysis informed by social semiotics, we analyze how the semantic variations in students’ representations correspond to the recurring genres they were enacting. We found a general pattern in the use and creation of representations across different scientific genres that support the theory of a mutual contextualization between genre and representation construction.