Glutamine switches vascular smooth muscle cells to synthetic phenotype through inhibiting miR-143 expression and upregulating THY1 expression.

Aims: Vascular smooth muscle cells (VSMCs) are involved in the pathogenesis of many human cardiovascular diseases. They modulate their phenotype from "contractile" to "synthetic" in response to changes in local environmental cues. How glutamine regulates the differentiation of VSMCs and the underlying mechanisms remain largely unknown.

[Expression and purification of truncated fragment of extracellular segment of sodium pump alpha3 subunit in Escherichia coli by in-fusion technology].

Objective: To construct prokaryotic expression system for expressing, purifying and identifying truncated fragment of extra-cellular segment of sodium pump alpha3 subunit with pGEX-6P-1 GST gene fusion system in Escherichia coli by in-fusion technology.

Methods: According to the conservative sequence of M1-M2 and M3-M4 extra-cellular gene fragments of sodium pump a3 subunit, which published in GenBank, a serial of primers and gene fragments was designed, and directly synthesized to fuse the above two gene fragments. The fusion gene was fused with gene-specific primers by PCR, and then fusion gene fragment was fused into the single stranded homology regions of vector pGEX-6P-1 by in-fusion cloning to construct recombinant vector pGEX-Trf-alpha3 (Truncated fragment of extracellular segment of sodium pump alpha3 subunit, Trf-alpha3).

[Activity identification of peptide containing rat sodium pump α2 subunit M1-M2 extramembrane fragment in vitro].

In order to explore the activity of a peptide containing rat sodium pump α2 subunit M1-M2 extramembrane fragment (RES2 derivative) in vitro, the peptide (Leu-Ala-Ala-Met-Glu-Asp-Glu-Pro-Ser-Asn-Asp-Asn-Gly-Gly-Gly-Ser) was synthesized by peptide synthesizer with Fmoc method and purified by high performance liquid chromatography (HPLC). Its binding activity was identified by radioligand-receptor binding assay (RRA) and its bioactivity was measured by erythrocyte (86)Rb uptake. The results of saturation binding experiment and competitive binding experiment showed that the synthesized RES2 derivative had the capability to bind to (3)H-ouabain.