Fusing PHOSPHO1 and MNeonGreen: Celestial or cellular imaging? Description: This image shows an MC3T3 osteoblast transiently transfected with a PHOSPHO1-MNeonGreen fusion construct, in order to track matrix vesicle production and biogenesis in in vitro cultures. 16 hours after transfection the cells were fixed and costained with Phalloidin-594 and Hoescht. This shows high expression of cytoplasmic PHOSPHO1 (green) and delicate protrusions, leading to extracellular puncta also positive for PHOSPHO1. The actin cytoskeleton (red) appears to form stress fibre-like focal points at these areas also, suggesting a potential role in matrix vesicle biogenesis.