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Spiny brown dinoflagellate cysts are commonly used as sea‐ice indicators in the Arctic, but their biological affinities are not well known. We present the first indication of hitherto temperate Protoperidinium tricingulatum in the Arctic based on single‐cell LSU rDNA sequencing from sediments of the Disko Bay‐Vaigat Sound, West Greenland. The morphological similarity of the sequenced cyst morphotype to the sea‐ice indicator Islandinium? cezare morphotype 1 is striking. The morphology of the isolated cysts, as well as those observed in the total cyst assemblage following standard palynological preparation, both resemble either I.? cezare morphotype 1 or P. tricingulatum, suggesting that the specimens may in fact be close morphological variants of the same species. In addition, nine LSU rDNA sequences were obtained from morphological variants assigned to Islandinium minutum s.l.: including both subspecies minutum and subspecies barbatum. The two subspecies could not be differentiated based on partial LSU rDNA sequencing. Overall, Arctic spiny brown dinoflagellate cyst species may be morphologically more diverse and taxonomically more complex than shown earlier and further genetic and morphological studies are needed. Importantly, the value of cysts as palaeoecological indicators depends on a sound understanding of their biological affinity and taxonomy. [ABSTRACT FROM AUTHOR]

Cells sense extracellular matrix‐induced biophysical signals, which are transduced into intracellular signaling cascades, and trigger a series of cell responses, including adhesion, migration, and lineage commitment. Traditionally, in in vitro context, monofactorial approaches are employed to control cell fate, despite the fact that in vivo cells are exposed simultaneously to a diverse range of signals. Herein, an overview of key mechanotransduction pathways is first provided. Conventional single‐factor and contemporary multifactorial methodologies, based on substrate rigidity and surface topography, are then reviewed to recapitulate in vitro the in vivo niche, in an attempt to elucidate the underlying mechanisms involved in human mesenchymal stromal cell‐material interactions. [ABSTRACT FROM AUTHOR]