Results for “VIn3” | Engineering Papers

DOE OSTI2020

Materials Data on VIn3 by Materials Project

VIn3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. V is bonded to twelve equivalent In atoms to form VIn12 cuboctahedra that share corners with six equivalent VIn12 cuboctahedra, corners with twelve equivalent InV4In8 cuboctahedra, edges with eighteen equivalent InV4In8 cuboctahedra, faces with eight equivalent VIn12 cuboctahedra, and faces with twelve equivalent InV4In8 cuboctahedra. There are six shorter (3.09 Å) and six longer (3.17 Å) V–In bond lengths. In is bonded to four equivalent V and eight equivalent In atoms to form InV4In8 cuboctahedra that share corners with four equivalent VIn12 cuboctahedra, corners with fourteen equivalent InV4In8 cuboctahedra, edges with six equivalent VIn12 cuboctahedra, edges with twelve equivalent InV4In8 cuboctahedra, faces with four equivalent VIn12 cuboctahedra, and faces with sixteen equivalent InV4In8 cuboctahedra. There are a spread of In–In bond distances ranging from 3.03–3.21 Å.

36 MATERIALS SCIENCE↗

NASA NTRS1997

Vinculin promotes cell spreading by mechanically coupling integrins to the cytoskeleton

Mouse F9 embryonic carcinoma 5.51 cells that lack the cytoskeletal protein vinculin spread poorly on extracellular matrix compared with wild-type F9 cells or two vinculin-transfected clones (5.51Vin3 and Vin4; Samuels et al., 1993, J. Cell Biol. 121, 909-921). In the present study, we used this model system to determine how the presence of vinculin promotes cytoskeletal alterations and associated changes in cell shape. Microscopic analysis of cell spreading at early times, revealed that 5.51 cells retained the ability to form filopodia; however, they could not form lamellipodia, assemble stress fibers, or efficiently spread over the culture substrate. Detergent (Triton X-100) studies revealed that these major differences in cell morphology and cytoskeletal organization did not result from differences in levels of total polymerized or cross-linked actin. Biochemical studies showed that 5.51 cells, in addition to lacking vinculin, exhibited slightly reduced levels of alpha-actinin and paxillin in their detergent-insoluble cytoskeleton. The absence of vinculin correlated with a decrease in the mechanical stiffness of the integrin-cytoskeleton linkage, as measured using cell magnetometry. Furthermore, when vinculin was replaced by transfection in 5.51Vin3 and 5.51Vin4 cells, the levels of cytoskeletal-associated alpha-actinin and paxillin, the efficiency of transmembrane mechanical coupling, and the formation of actin stress fibers were all restored to near wild-type levels. These findings suggest that vinculin may promote cell spreading by stabilizing focal adhesions and transferring mechanical stresses that drive cytoskeletal remodeling, rather than by altering the total level of actin polymerization or cross-linking.

NASA Program Space Biology↗