Exploring an EIT as a tool for accessing sociophonetic knowledge

Elicited imitation tasks (EITs)—tasks that involve repetition of sentence-length stimuli—have received increased attention as tools for measuring general L2 proficiency and implicit knowledge of grammatical features (Kostromitina & Plonsky, 2022). The present study diverges from predecessors by exploring the use of an EIT for accounting for sociophonetic knowledge. Complementing work on the acquisition of Peninsular phonetic/phonological variants (e.g., George, 2014), the present study investigates acquisition of /θ/ by 25 US learners of Spanish studying abroad in a 6-week immersion program in León, Spain. Learners completed an oral monologic role-play task and a 36-item Spanish EIT (Solon et al., 2019) modified to include Peninsular phonetic features, during their first and last weeks abroad. An at-home (AH) group of 15 second-year university Spanish learners completed the same tasks following a similar timeline. The modified EIT included 30 instances of [θ]. Audio-recorded EIT repetitions were assessed in three ways: (1) using Ortega et al.’s (2002) 5-point rubric for an overall proficiency score per learner, (2) for the number of lexical items containing [θ] successfully reproduced (regardless of pronunciation of the phone), and (3) for the number of instances of [θ] reproduced as [θ]. In the oral role-plays, potential contexts for /θ/ were identified (n = 1,230) and coded for realization. Mixed-effects regressions were used to examine change in EIT scores and [θ] usage over time. Preliminary results suggest that learners studying abroad in Spain demonstrated increased ability to process [θ], as indicated by higher rates of repetition of lexical items containing [θ] at the end of the program than the beginning. Similar gains were not observed for AH learners, suggesting that improvement was not only the result of repeating the task. Nonetheless, rates of [θ] production were low even at Time 2. Learners’ increased ability to comprehend and repeat EIT content containing [θ] despite no concomitant increase in production suggests that learners gained sociophonetic knowledge during this short sojourn and that this knowledge gain likely would not have been captured by analyzing production alone. Findings support the utility of EITs as a tool for tracking acquisition of sociolinguistically variable phonetic/phonological features

TNK1 is a ubiquitin-binding and 14-3-3-regulated kinase that can be targeted to block tumor growth.

TNK1 is a non-receptor tyrosine kinase with poorly understood biological function and regulation. Here, we identify TNK1 dependencies in primary human cancers. We also discover a MARK-mediated phosphorylation on TNK1 at S502 that promotes an interaction between TNK1 and 14-3-3, which sequesters TNK1 and inhibits its kinase activity. Conversely, the release of TNK1 from 14-3-3 allows TNK1 to cluster in ubiquitin-rich puncta and become active. Active TNK1 induces growth factor-independent proliferation of lymphoid cells in cell culture and mouse models. One unusual feature of TNK1 is a ubiquitin-association domain (UBA) on its C-terminus. Here, we characterize the TNK1 UBA, which has high affinity for poly-ubiquitin. Point mutations that disrupt ubiquitin binding inhibit TNK1 activity. These data suggest a mechanism in which TNK1 toggles between 14-3-3-bound (inactive) and ubiquitin-bound (active) states. Finally, we identify a TNK1 inhibitor, TP-5801, which shows nanomolar potency against TNK1-transformed cells and suppresses tumor growth in vivo