AIM: To study the effect of calcium sensing receptor (CaSR) on icariin (ICA) induced mouse embryonic stem cells ( mESCs) to differentiate into cardiomyocytes in vitro.METHODS:mESCs were cultured to embry-oid bodies ( EBs) by direct suspension method and the differentiation of EBs into cardiomyocytes was induced by ICA.The expression of cardiac specific proteinsα-actinin and cardiac troponin-I ( cTnI) was analyzed by Western blot and immuno-fluorescence.The differentiation rate was determined by flow cytometry.The ultrastructure of the derived cardiomyocytes was further characterized by transmission electron microscopy.The expression of cardiac-specific transcription factors Nkx2.5 and GATA-4,as well as CaSR was detected by Western blot.RESULTS: After induction with ICA, the positive characteristics of myocardial cells appeared in the EBs cultured for 2 d.The expression of cardiac-specific sarcomeric pro-tein actinin (α-actinin) and cTnI showed an overall upward trend by Western blot in different phases of ICA induced differ-entiation.The expression of CaSR, Nkx2.5 and GATA-4 was the highest at an early stage of ICA-induced differentiation. Neomycin (an activator of CaSR) up-regulated CaSR, NKx2.5 and GATA-4 expression in the EBs at early stage of ICA-in-duced differentiation, all of which were reversed by NPS2390 ( an inhibitor of CaSR) .CONCLUSION:CaSR is function-ally expressed in mESC-derived cardiomyocytes, and activation of CaSR is involved in the differentiation of mESCs into car-diomyocytes by facilitating the expression of NKx2.5 and GATA-4.

The aim of this study is to construct a bifunctional fusion protein, which can conjugate both human red blood cells and antibodies against classical swine fever virus (CSFV). We respectively amplified 2E8ScFv and mE2 genes from different recombinant vectors, in which 2E8ScFv gene is the single chain Fv gene against H antigen of human red blood cells, whereas mE2 gene is the main antigen coding region gene of CSFV E2 protein. We used overlap extension PCR to obtain an artificial fusion gene segment 2E8mE2 containing genes of Both 2E8ScFv and mE2, then ligated into the expression vector pET-DsbA and expressed in Escherichia coli BL21(DE3) PlysS host cells, after induced with IPTG the target fusion protein was successfully expressed and identified in inclusion bodies by SDS-PAGE and Western blotting. We purified the fusion protein and renatured it from inclusion bodies to obtain a native state of well biological activity. The Erythrocyte agglutination test results indicated that the fusion protein can conjugate both human red blood cells and antibodies of CSFV.
Erythrocytes ; immunology ; Escherichia coli ; genetics ; metabolism ; Humans ; Immunoglobulin Fragments ; biosynthesis ; genetics ; immunology ; Immunoglobulin Variable Region ; biosynthesis ; genetics ; immunology ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Single-Chain Antibodies ; biosynthesis ; genetics ; Viral Envelope Proteins ; biosynthesis ; genetics

Lipoprotein lipase (LPL) is a key enzyme in lipid and lipoprotein metabolism. LPL mainly hydrolyzes triglyceride-rich lipoproteins and provides free fatty acid (FFAs) for metabolic tissues. LPL acts as a molecular bridge between lipoproteins and cell surface lipoprotein receptors, facilitating lipoprotein uptake. Recent studies have shown that LPL is widely expressed in tissues. LPL has a variety of physiological functions, Lipoprotein lipase (LPL) is a key enzyme in lipid and lipoprotein metabolism. LPL mainly hydrolyzes triglyceride-rich lipoproteins and provides free fatty acid (FFAs) for metabolic tissues. LPL acts as a molecular bridge between lipoproteins and cell surface lipoprotein receptors, facilitating lipoprotein uptake. Recent studies have shown that LPL is widely expressed in tissues. LPL has a variety of physiological functions, which regulates lipid metabolism and energy balance in the brain. Besides, it is closely related to Alzheimer's disease. This paper mainly reviews the latest research progress of LPL in the nervous system and provides new targets for the treatment and prevention.