Neural stem cells are multipotent cells that can generate neurons, astrocytes, and oligodendrocytes in the central nervous system, in addition to their capacity to self-renew as stem cells. A major protein constituent of the microenvironment of neural stem cells is laminin, providing biological signals to control cell migration, proliferation, and differentiation through interaction with various types of integrins. Integrin receptors serve as a transducer through which forces are transmitted between cells and the extracellular matrix through a process termed mechanotransduction to sense and react to the biological cues generated. This project’s long-term goal is to investigate the use of short sequences from laminin to mediate force signaling to neural stem cells and if this signaling has implications in diseases and aging.
To initiate these studies, we first must appropriately label the stem cells for study. Filamentous actin (F-actin) visualization is considered a key component to understanding structural cytoskeletal dynamics through the linkage between cells and the extracellular matrix. Although F-actin visualization in fixed samples has been used for years, it has been a challenge to visualize the F-actin in live cells without interfering with actin dynamics, especially in hard-to-transduce cells like neural stem cells. LifeAct is a short, 17-amino acid peptide used in both living and fixed eukaryotic cells to visualize F-actin. We have introduced LifeAct into neural stem cells using lentiviral vectors and examine the labeling technique’s effect on cell viability.