Liprin-α1 assembles in glucose-dependent clusters at the β cell–ECM interface. (A–D) Isolated β cells cultured on laminin-511 were stimulated with 16.7 mM glucose or 40 mM K⁺ and fixed and immunostained for endogenous liprin-α1. In 2.8 mM glucose conditions, liprin-α1 showed punctate distribution at the β cell–laminin interface. These liprin-α1 puncta showed increased fluorescence intensity after 16.7 mM glucose stimulation but not 40 mM K⁺ stimulation (n = 3 animals, one-way ANOVA followed by Tukey’s multiple comparisons test). (D–G) Live-cell super-resolution spatial array confocal microscopy in β cells expressing GFP–liprin-α1, imaged at the β cell–laminin interface. (D) Snapshot of cells at 0 min (2.8 mM glucose), 15 min (16.7 mM glucose), and 30 min (16.7 mM glucose). (B) A kymograph showing liprin fluorescence over time along a line (indicated in yellow in Fig. 4 D) shows dynamic changes in liprin clusters, appearing and disappearing from the β cell–laminin interface over time. Clusters appear brighter and more abundant after glucose stimulation compared with before stimulation, (F) also apparent in line scans taken before (orange) and after (green) glucose stimulation. (G) Fluorescence changes over time of a region of interest (indicated in red in Fig. 4, D and E) shows the transient appearance of a single GFP–liprin-α1 cluster. (H–L) GFP–liprin-α1 cluster size and abundance (number of clusters per cell) tracked over time. Both size of clusters and number of clusters per cell increased after glucose stimulation (n = 3 animals, Student’s t test, unpaired, equal variance).