Interference with ACSL1 gene in bovine adipocytes: Transcriptome profiling of circRNA related to unsaturated fatty acid production.

Long-chain acyl-CoA synthetase 1 (ACSL1) is a member of the acyl-CoA synthetase family that plays a vital role in lipid metabolism. We have previously shown that the ACSL1 gene regulates the composition of unsaturated fatty acids (UFAs) in bovine skeletal muscle, which in turn regulates the fatty acid synthesis and the generation of lipid droplets. Here, we used RNA-Seq to screen circRNAs that regulated the expression of ACSL1 gene and other UFA synthesis-related genes by RNA interference and noninterference in bovine adipocytes. The results of KEGG pathway analysis showed that the parental genes of differentially expressed (DE)-circRNAs were primarily enriched in the adipocytokine signaling pathway. The prediction results showed that novel_circ_0004855, novel_circ_0001507, novel_circ_0001731, novel_circ_0005276, novel_circ_0002060, novel_circ_0005405 and novel_circ_0004254 regulated UFA synthesis-related genes by interacting with the related miRNAs. These results could help expand our knowledge of the molecular mechanisms of circRNAs in the regulation of UFA synthesis in bovine adipocytes.

Interference With ACSL1 Gene in Bovine Adipocytes: Transcriptome Profiling of mRNA and lncRNA Related to Unsaturated Fatty Acid Synthesis.

The enzyme long-chain acyl-CoA synthetase 1 (ACSL1) is essential for lipid metabolism. The ACSL1 gene controls unsaturated fatty acid (UFA) synthesis as well as the formation of lipid droplets in bovine adipocytes. Here, we used RNA-Seq to determine lncRNA and mRNA that regulate UFA synthesis in bovine adipocytes using RNA interference and non-interference with ACSL1. The corresponding target genes of differentially expressed (DE) lncRNAs and the DE mRNAs were found to be enriched in lipid and FA metabolism-related pathways, according to GO and KEGG analyses. The differentially expressed lncRNA- differentially expressed mRNA (DEL-DEM) interaction network indicated that some DELs, such as TCONS_00069661, TCONS_00040771, TCONS_ 00035606, TCONS_00048301, TCONS_001309018, and TCONS_00122946, were critical for UFA synthesis. These findings assist our understanding of the regulation of UFA synthesis by lncRNAs and mRNAs in bovine adipocytes.

Effects of overexpression of ACSL1 gene on the synthesis of unsaturated fatty acids in adipocytes of bovine.

There exists a positive correlation between the unsaturated fatty acids (UFA) content in the bovine species and their taste and nutritional significance. Long-chain acyl-CoA synthetase 1 (ACSL1) is known to be involved in lipid synthesis as well as fatty acid transport and degradation. This gene has been identified as the key candidate gene for regulating lipid composition in the bovine skeletal muscle; however, its mechanism of action in regulating UFA synthesis in bovine adipocytes is unclear. In this study, we used a recombinant adenovirus vector (Ad-ACSL1) to overexpress the ACSL1 gene using Ad-NC (recombinant adenovirus of green fluorescent protein) as the control. Quantitative real-time PCR (qRT-PCR) was done to examine the gene expression associated with the synthesis of UFA, followed by the analysis of the fatty acid composition. Oil red O staining was done to examine the aggregation of lipid droplets. We found that ACSL1 overexpression was associated with an upregulated expression of PPARγ, FABP3, ACLY, SCD1, and FASN, and downregulated expression of CPT1A. Additionally, ACSL1 overexpression resulted in elevated saturated fatty acid content, especially C16:0 and C18:0, than the control group (Ad-NC cells) (p < 0.05). Furthermore, the overexpression of ACSL1 enhanced the proportion of eicosapentaenoic acid (EPA), decreased the proportion of C22:4, and significantly upregulated polyunsaturated fatty acid (PUFA) content. These results were supported by oil red O staining, which revealed an increase in the lipid droplets in bovine adipocytes after the overexpression of the ACSL1 gene. Thus, the results of this study indicated that ACSL1 positively regulated PUFA synthesis in bovine adipocytes.

Patterning a Superhydrophobic Area on a Facile Fabricated Superhydrophilic Layer Based on an Inkjet-Printed Water-Soluble Polymer Template.

An elaborated surface with a superhydrophilic area and a superhydrophobic area was fabricated by inkjet printing a water-soluble polymer template on a superhydrophilic layer. Titanate was used to generate the superhydrophilic layer with an in situ reaction. A water-soluble polymer template was inkjet printed on the facile fabricated superhydrophilic layer. Superhydrophobic treatment was carried out on the inkjet-printed surface with perfluorinated molecules. A superhydrophilic-superhydrophobic patterned surface (SSPS) was obtained by washing out the water-soluble polymer template. Various patterns of SSPS were fabricated with the different water-soluble polymer templates. Then, adhesion and deposition of water droplets were studied on the SSPS with the different wetting abilities on the surface. Meanwhile, a microreaction with a microfluidic chip was realized on the SSPS. In this work, systematic research on fabricating an SSPS based on a facile fabricated superhydrophilic layer with an inkjet-printed water-soluble polymer template is presented. It will have great potential for patterning materials, fabricating devices, and researching interfaces, such as microdroplet self-removal, analyte enrichment, and liquid-liquid interface reaction.

Transcriptional Regulation of the Bovine Fatty Acid Transport Protein 1 Gene by Krüppel-Like Factors 15.

Oleic acid is a major monounsaturated fatty acid, which accounts for about 33% of the fatty acid content in beef and is considered to have the least negative effect on serum cholesterol levels. Fatty acid transport protein 1 (FATP1), an integral membrane protein that facilitates long-chain fatty acid (LCFA) influx, is involved in the genetic network for oleic acid synthesis in beef. Its expression exhibits significant positive correlations with intramuscular fat (IMF) content in the longissimus thoracis. However, the expression mechanism of SLC27A1 or FATP1 is still unclear. To elucidate the molecular mechanisms involved in bovine SLC27A1 regulation, we cloned and characterized the promoter region of SLC27A1. By applying 5'-rapid amplification of cDNA end analysis, we identified two alternative splice variants of this gene. Using a series of 5' deletion promoter plasmids in luciferase reporter assays, we found that the core promoter was 96 base pairs upstream from the transcription initiation site. Electrophoretic mobility shift assay combined with a site-directed mutation experiment demonstrated that KLF15 binding to the promoter region drives the SLC27A1 transcription. KLF15 plays an essential role in adipogenesis and skeletal muscle lipid flux. Thus, these results might provide further information on the regulatory roles of SLC27A1 gene in mediating the lipid composition in beef.

Balance of coordination and hydrophobic interaction in the formation of bilayers in metal-coordinated surfactant mixtures.

Metal-ligand coordination and hydrophobic interaction are two significant driving forces in the aggregation of mixtures of M(n+) surfactants and alkyldimethylamine oxide (CnDMAO) in aqueous solutions. The coordinated systems exhibit rich aggregation behavior. This study investigated the effect of M(n+) ions (Zn(2+), Ca(2+), Ba(2+), Al(3+), Fe(3+), La(3+), Eu(3+), and Tb(3+)) and hydrophobic chains (hydrocarbon and fluorocarbon) on the formation of metal-coordinated bilayers. We found that fluorocarbon chains and branched hydrocarbon chains are preferable to the corresponding linear hydrocarbon chains for the formation of an Lα phase. Moreover, Lα phases formed by fluorocarbon chains exhibited higher viscoelasticity than ones formed by the hydrocarbons, and the bilayers formed by branched chains were rather flexible, revealing obvious undulation. The construction of bilayers was also strongly affected by metal ions due to their variable coordination ability with CnDMAO. Our results contribute to the understanding of the formation of metal-coordinated bilayers, which is driven by the interplay of noncovalent forces.

Effect of hydrophilic groups of Ca surfactants and hydrophobic chains of C(n)DMAO on coordinated vesicle formation.

The effects of hydrophilic headgroups of Ca surfactants, calcium dodecylsulfate (Ca(DS)(2)), calcium dodecylsulfonate (Ca(DSA)(2)), and calcium laurate (CaL(2)) and hydrophobic chains of alkyldimethylamine oxide (C(n)DMAO, n = 12, 14, 16) on the formation of Ca(2+)-ligand coordinated vesicles was investigated in detail. On the basis of phase behavior studies, rheological properties and freeze-fracture transmission electron microscope (FF-TEM) images were measured. Quite different phase behaviors were observed in different surfactant systems. For a Ca surfactant with a highly polar group, Ca(DS)(2), vesicles were observed in all Ca(DS)(2)/C(n)DMAO (n = 12, 14, and 16) systems, whereas for Ca surfactant with lower polar group, Ca(DSA)(2), vesicles can form in Ca(DSA)(2)/C(n)DMAO systems of n = 14 and 16 but not for n = 12. For CaL(2), the surfactant with the least polar group, vesicles form only in the CaL(2)/C(16)DMAO system. The results demonstrate that in the systems formed by Ca surfactants and C(n)DMAO, the formation of vesicles is driven not only by interaction between Ca(2+) and the N → O groups of C(n)DMAO but also by electrostatic and hydrophobic interactions. Vesicles prefer to form in Ca surfactants with highly polar headgroups and C(n)DMAO with long chain length.