Integrins are an important family of adhesion molecules that were first discovered two decades ago. Integrins are transmembrane heterodimeric glycoprotein receptors consisting of α and β subunits, and are comprised of an extracellular domain, a transmembrane domain, and a cytoplasmic tail. Therein, integrin cytoplasmic domains may associate directly with numerous cytoskeletal proteins and intracellular signaling molecules, which are crucial for modulating fundamental cell processes and functions including cell adhesion, proliferation, migration, and survival. The purpose of this review is to describe the unique structure of each integrin subunit, primary cytoplasmic association proteins, and transduction signaling pathway of integrins, with an emphasis on their biological functions.

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Soybean agglutinin (SBA) is an anti-nutritional factor of soybean, affecting cell proliferation and inducing cytotoxicity. Integrins are transmembrane receptors, mediating a variety of cell biological processes. This research aims to study the effects of SBA on cell proliferation and cell cycle progression of the intestinal epithelial cell line from piglets (IPEC-J2), to identify the integrin subunits especially expressed in IPEC-J2s, and to analyze the functions of these integrins on IPEC-J2 cell cycle progression and SBA-induced IPEC-J2 cell cycle alteration. The results showed that SBA lowered cell proliferation rate as the cell cycle progression from G0/G1 to S phase (P < 0.05) was inhibited. Moreover, SBA lowered mRNA expression of cell cycle-related gene CDK4, Cyclin E and Cyclin D1 (P < 0.05). We successfully identified integrins α2, α3, α6, β1, and β4 in IPEC-J2s. These five subunits were crucial to maintain normal cell proliferation and cell cycle progression in IPEC-J2s. Restrain of either these five subunits by their inhibitors, lowered cell proliferation rate, and arrested the cells at G0/G1 phase of cell cycle (P < 0.05). Further analysis indicated that integrin α2, α6, and β1 were involved in the blocking of G0/G1 phase induced by SBA. In conclusion, these results suggested that SBA lowered the IPEC-J2 cell proliferation rate through the perturbation of cell cycle progression. Furthermore, integrins were important for IPEC-J2 cell cycle progression, and they were involved in the process of SBA-induced cell cycle progression alteration, which provide a basis for further revealing SBA anti-proliferation and anti-nutritional mechanism.

2D lamellar membranes hold great promise in efficient molecular separations of liquid and gas mixtures. However, the simultaneous realization of high permeation and precise sieving (i.e., overcoming the permeation-rejection tradeoff ) of membranes poses a great challenge. Inspired by the structures and functions of the beetle's back, the heterostructured lamellar membranes fabricated through facile and controllable electrostatic atomization method are reported. Particularly, hydrophobic polymer clusters are patterned on hydrophilic laminate (graphene oxide) surfaces to realize the hydrophilic/hydrophobic heterostructure. It shows that the fast dissolution for nonpolar solvents is achieved by the strong affinity polymer clusters, and the ultralow-barrier diffusion is achieved by the weak affinity laminate channels. Therefore, the permeance is remarkably enhanced (over 7 times for nonpolar solvents), while fully retaining membrane rejection. In contrast, hydrophilic clusters are patterned on hydrophobic laminate (reduced graphene oxide) surfaces and exhibit similar behaviors toward polar solvents. Furthermore, the lamellar membrane displays highly ordered layer-by-layer stacking, affording precise molecular rejection. Besides, the lamellar membrane acquires lower thermodynamic energy and hence superior stability under ultrasonic and strong acid or alkali environments, manifesting great potential for long-term practical operation.

The silicone rubber (SR) nanocomposites have been successfully prepared via the in situ hydrosilylation reaction in the presence of pristine ZnO and vinyl silane modified ZnO ( SiVi@ ZnO ) nanoparticles. The structure of the pristine ZnO and SiVi @ ZnO nanoparticles were analyzed by the Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD), respectively. The morphology, thermal stabilities, mechanical properties and thermal conductivity of the nanocomposites were also investigated. The results showed that the SiVi @ ZnO nanoparticles exhibit a better dispersion in the silicone rubber than the pristine ZnO nanoparticles. The corresponding silicone rubber/ SiVi @ ZnO (SR/ SiVi @ ZnO ) nanocomposites showed higher mechanical properties and thermal conductivity due to the better dispersion in silicone rubber matrix.