Files
Abstract
Atomic force microscopy has advanced to the point that in situ measurements of biological systems can be made at the single-molecule level, providing information on rare states that are lost in standard ensemble measurements and allowing specific detection of proteins and polysaccharides. One such system is that of the signaling pathway Slit-Roundabout (Robo), which has been implicated in the development of the nervous system, heart, and cancer. The Slit-Robo complex is stabilized and regulated by heparan sulfate (HS), a linear, structurally-heterogeneous polysaccharide expressed widely on mammalian cell membranes. Thus, better understanding of HSs regulatory role could allow us to target therapies related to this pathway. Using dynamic force spectroscopic methods, this research shows that is possible to create a model system allowing for the measurement of single-molecule interactions between the HS variant heparin and the Robo1 protein, elucidating the kinetics of the interaction using the entire polysaccharide in ambient conditions.