Life Sciences Commons^™

Effect Of The Physical Micro-Environment On Cell Adhesion And Force Exertion, Mohamad Eftekharjoo

Mechanical & Aerospace Engineering Theses & Dissertations

Physical characteristics of the microenvironment, such as geometry and stiffness, influence cell adhesion and contractile forces. Here, we determined how these physical factors influenced cell force exertion and adhesion in two specific contexts that have broad relevance.

Fibroblasts are cells in connective tissues that interact with a fibrous extracellular matrix (ECM) that have a predominantly one-dimensional (1D) (fibrillar) geometry. However, it has been unclear as to how the 1D nature of the fibrillar ECM influences the forces exerted by fibroblasts. Here, we used fibroblast cells adherent on fibronectin lines on polyacrylamide (PAA) gels of stiffness 13 and 45 kPa to …

Embryonic Chicken Fibroblast Collagen Binding Proteins: Distribution, Role In Substratum Adhesion, And Relationship To Integrins, Roy C. Ogle, A. Jeannette Potts, Marchall Yacoe, Charles D. Little

School of Medical Diagnostics & Translational Sciences Faculty Publications

Collagen binding proteins (CBP) are hydrophobic, cell surface polypeptides, isolated by collagen affinity chromatography. Antibodies to CBPs inhibit the attachment of embryonic chicken heart fibroblasts to native type I collagen fibrils in a dose-dependent manner. The CBP antibodies also induce rounding and detachment of cells adherent to a planar substratum. This process of antibody-mediated substratum detachment resulted in a clustering of CBP and cell-associated extracellular matrix at the cell surface, and the rearrangement of filamentous actin. Other functional studies showed that cells grown within a three-dimensional gel of type I collagen cannot be immunostained at the cell surface with CBP …

Modulation Of Queuine Uptake In Cultured Human Fibroblasts By Phorbol Esters And Interferons, Debra L. Crane

Chemistry & Biochemistry Theses & Dissertations

Queuosine, a nucleoside found exclusively in the first position of the anticodon of transfer RNA (tRNA), is generated post-transcriptionally in an exchange of guanine for queuine by the modifying enzyme tRNA-guanine ribosyltransferase. Phorbol ester tumor promoters were shown to induce queuine hypomodified tRNA, and that phorbol ester action was due, in part, to inhibition of queuine transport across the cell membrane. An unidentified protein designated conditioned medium factor (CMF) that potentiated a phorbol-induced inhibition of queuine uptake was also documented. We suggest here that phorbol ester-induced inhibition of queuine uptake is not a significant factor in inducing queuine-deficient tRNA although …