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Controlling cellular shape with protein micropatterning can mimic physiological morphologies and has been shown to improve reproducibility, enhancing our ability to collect statistics on single-cell behaviors. It has also advanced efforts in developing human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) as a promising human model for studies of heart structure and function. hiPSC-CMs have key physiological differences from primary human cardiomyocytes (CMs), including lower sarcomere alignment and contractility, smaller area and lower aspect ratio, and lower force production. Protein micropatterning has been demonstrated to make hiPSC-CMs behave more like primary human CMs across these metrics. However, these micropatterned models typically use only extracellular matrix (ECM) proteins and have not investigated whether providing a protein associated with CM-CM interactions, such as N-cadherin, further enhances hiPSC-CM structure and function. Here, we developed a novel dual-protein patterning process to geometrically control single-cell CM placement on deformable hydrogels suitable for traction force microscopy (TFM). The patterns were comprised of rectangular laminin islands for attachment across the majority of the cell area, with N-cadherin end-caps imitating cell-cell interactions. We first photopatterned two proteins on a glass coverslip using a two-step process with photomolecular adsorption of proteins. After both photopatterning steps were complete, we transferred the pattern from the coverslip to a physiologically relevant ~10-kPa polyacrylamide hydrogel. We seeded alpha-actinin-tagged …