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Web-based experiments are gaining momentum in motor learning research because of the desire to increase statistical power, decrease overhead for human participant experiments, and utilize a more demographically inclusive sample population. However, there is a vital need to understand the general feasibility and considerations necessary to shift tightly controlled human participant experiments to an online setting. We developed and deployed an online experimental platform modeled after established in-laboratory visuomotor rotation experiments to serve as a case study examining remotely collected data quality for an 80-min experiment. Current online motor learning experiments have thus far not exceeded 60 min, and current online crowdsourced studies have a median duration of approximately 10 min. Thus, the impact of a longer-duration, web-based experiment is unknown. We used our online platform to evaluate perturbation-driven motor adaptation behavior under three rotation sizes (±10°, ±35°, and ±65°) and two sensory uncertainty conditions. We hypothesized that our results would follow predictions by the relevance estimation hypothesis. Remote execution allowed us to double (n = 49) the typical participant population size from similar studies. Subsequently, we performed an in-depth examination of data quality by analyzing single-trial data quality, participant variability, and potential temporal effects across trials. Results replicated in-laboratory findings and provided insight on the effect of induced sensory uncertainty on the relevance estimation hypothesis. Our experiment also highlighted several specific challenges associated with online data collection including potentially smaller effect sizes, higher data variability, and lower recommended experiment duration thresholds. Overall, online paradigms present both opportunities and challenges for future motor learning research.

 

Social telepresence robots (i.e., telerobots) are used for social and learning experiences by children. However, most (if not all) commercially available telerobot bodies were designed for adults in corporate or healthcare settings. Due to an adult-focused market, telerobot design has typically not considered important factors such as age and physical aspect in the design of robot bodies. To better understand how peer interactants can facilitate the identities of remote children through personalization of robot bodies, we conducted an exploratory study to evaluate collaborative robot personalization. In this study, child participants (N=28) attended an interactive lesson on robots in our society. After the lesson, participants interacted with two telerobots for personalization activities and a robot fashion show. Finally, participants completed an artwork activity on robot design. Initial findings from this study will inform our continued work on telepresence robots for virtual inclusion and improved educational experiences of remote children and their peers. 

AGAMOUS-like 15 (AGL15) is a member of the MADS-domain transcription factor (TF) family. MADS proteins are named for a conserved domain that was originally from an acronym derived from genes expressed in a variety of eukaryotes (MCM1-AGAMOUS-DEFICIENS-SERUM RESPONSE FACTOR). In plants, this family has expanded greatly, with more than one-hundred members generally found in dicots, and the proteins encoded by these genes have often been associated with developmental identity. AGL15 transcript and protein accumulate primarily in embryos and has been found to promote an important process called plant regeneration via somatic embryogenesis (SE). To understand how this TF performs this function, we have previously used microarray technologies to assess direct and indirect responsive targets of this TF. We have now revisited this question using next generation sequencing (NGS) to both characterize in vivo binding sites for AGL15 as well as response to the accumulation of AGL15. We compared these data to the prior microarray results to evaluate the different platforms. The new NGS data brought to light an interaction with brassinosteroid (BR) hormone signaling that was “missed” in prior Gene Ontology analysis from the microarray studies. 

Somatic embryogenesis (SE) is a process by which an embryo is derived from somatic tissue. Transcription factors (TFs) have been identified that control this process. One such TF that promotes SE is AGAMOUS‐like 15 (AGL15). Prior work has shown that AGL15 can both induce and repress gene expression. One way this type of dual function TF works is via protein interactions, so a yeast 2‐hybrid (Y2H) screen was undertaken. One intriguing protein with which AGL15 interacted in Y2H was LBD40. LBD40 encodes a LATERAL ORGAN BOUNDARIES (LOB)‐domain TF that is unique to plants and is primarily expressed during seed development. Here, we confirm the AGL15‐LBD40 interaction by quantitative assays andin plantaco‐immunoprecipation. We also document a role for LBD40, and the closely related protein LBD41, in supporting SE. To determine downstream genes potentially controlled by LBD40, chromatin immunoprecipitation followed by high throughput sequencing (ChIP‐seq) was used. More than 400 binding regions for LBD40 were consistently found genome‐wide. To determine genes responsive to LBD40/41 accumulation, RNA‐seq analysis of transcriptomes of wild‐type control and loss‐of‐functionlbd40/lbd41was performed. Combining these datasets provides insight into genes directly and indirectly controlled by these LOB domain TFs. The gene ontology (GO) enrichment analysis of these regulated genes showed an overrepresentation of biological processes that are associated with SE, further indicating the importance of LBD40 in SE. This work provides insight into SE, a poorly understood, but essential process to generate transgenic plants to meet agricultural demands or test gene function. This manuscript reports on experiments to understand the role that LDB40, a TF, plays in support of SE by investigating genes directly and indirectly controlled by LBD40 and examining physical and genetic interactions with other TFs active in SE. We uncover targets of LBD40 and an interacting TF of the MADS family and investigate targets involvement in SE.

 

Plants have amazing regenerative properties with single somatic cells, or groups of cells able to give rise to fully formed plants. One means of regeneration is somatic embryogenesis, by which an embryonic structure is formed that “converts” into a plantlet. Somatic embryogenesis has been used as a model for zygotic processes that are buried within layers of maternal tissues. Understanding mechanisms of somatic embryo induction and development are important as a more accessible model for seed development. We rely on seed development not only for most of our caloric intake, but also as a delivery system for engineered crops to meet agricultural challenges. Regeneration of transformed cells is needed for this applied work as well as basic research to understand gene function. Here we focus on a MADS-domain transcription factor, AGAMOUS-Like15 (AGL15) that shows a positive correlation between accumulation levels and capacity for somatic embryogenesis. We relate AGL15 function to other transcription factors, hormones, and epigenetic modifiers involved in somatic embryo development. 

AGAMOUS-like 15 (AGL15) is a member of the MADS domain family of transcription factors (TFs) that can directly induce and repress target gene expression, and for which promotion of somatic embryogenesis (SE) is positively correlated with accumulation. An ethylene-responsive element binding factor-associated amphiphilic repression (EAR) motif of form LxLxL within the carboxyl-terminal domain of AGL15 was shown to be involved in repression of gene expression. Here, we examine whether AGL15′s ability to repress gene expression is needed to promote SE. While a form of AGL15 where the LxLxL is changed to AxAxA can still promote SE, another form with a strong transcriptional activator at the carboxy-terminal end, does not promote SE and, in fact, is detrimental to SE development. Select target genes were examined for response to the different forms of AGL15.