scholarly journals Regulation of membrane KCNQ1/KCNE1 channel density by sphingomyelin synthase 1

2016 ◽  
Vol 311 (1) ◽  
pp. C15-C23 ◽  
Author(s):  
Meikui Wu ◽  
Makoto Takemoto ◽  
Makoto Taniguchi ◽  
Toru Takumi ◽  
Toshiro Okazaki ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Current Density ◽  
Short Hairpin Rna ◽  
Protein Kinase D ◽  
Dependent Manner ◽  
Hairpin Rna ◽  
Channel Density ◽  
Sphingomyelin Synthase ◽  
Short Hairpin ◽  
Channel Properties

Sphingomyelin synthase (SMS) catalyzes the conversion of phosphatidylcholine and ceramide to sphingomyelin and diacylglycerol. We previously showed that SMS1 deficiency leads to a reduction in expression of the K+ channel KCNQ1 in the inner ear (Lu MH, Takemoto M, Watanabe K, Luo H, Nishimura M, Yano M, Tomimoto H, Okazaki T, Oike Y, and Song WJ. J Physiol 590: 4029–4044, 2012), causing hearing loss. However, it remains unknown whether this change in expression is attributable to a cellular process or a systemic effect in the knockout animal. Here, we examined whether manipulation of SMS1 activity affects KCNQ1/KCNE1 currents in individual cells. To this end, we expressed the KCNQ1/KCNE1 channel in human embryonic kidney 293T cells and evaluated the effect of SMS1 manipulations on the channel using whole cell recording. Application of tricyclodecan-9-yl-xanthogenate, a nonspecific inhibitor of SMSs, significantly reduced current density and altered channel voltage dependence. Knockdown of SMS1 by a short hairpin RNA, however, reduced current density alone. Consistent with this, overexpression of SMS1 increased the current density without changing channel properties. Furthermore, application of protein kinase D inhibitors also suppressed current density without changing channel properties; this effect was nonadditive with that of SMS1 short hairpin RNA. These results suggest that SMS1 positively regulates KCNQ1/KCNE1 channel density in a protein kinase D-dependent manner.

scholarly journals Total Flavones Isolated from Lycium Barbarum L. Inhibit the Proliferation, Migration and Invasion of GlioblastomaU-87MG Cells by Decreasing Formyl Peptide Receptor 1 Expression

2021 ◽  
Author(s):  
Yuankui Chu ◽  
Qing Wang ◽  
Yuan Li ◽  
Yating Zhu ◽  
Baibin Pang ◽  
...  
Keyword(s):  
Short Hairpin Rna ◽  
Formyl Peptide Receptor ◽  
Nuclear Antigen ◽  
Migration And Invasion ◽  
Dependent Manner ◽  
Lycium Barbarum ◽  
Hairpin Rna ◽  
Formyl Peptide ◽  
Short Hairpin ◽  
Proliferating Cell

Abstract Background: To study the role and mechanisms of total flavones from Lycium barbarum L. (TFL) and FPR1 in the growth of glioblastoma U-87MG cells.Main Methods: CCK-8, wound-healing and Transwell were used for investigating proliferation, motility and invasion of U87 cells after treating with total flavones. RT-qPCR and Western blot were used to study the effect of total flavones on proliferating cell nuclear antigen (PCNA), matrix metalloproteinase2 (MMP2) and FPR1. The short hairpin RNA and FPR agonist fMLP were used to delineate the role of FPR1.Results: TFL was successfully isolated, and its concentration was determined to be 6.205 mg/l. TFL inhibited the proliferation, migration and invasion of U-87MG cells in a time and dose-dependent manner compared to controls. Decreasing FPR1 expression using short hairpin RNA significantly inhibited the migration and invasion of U-87MG cells. Notably, increased expression of FPR1 and treatment with FPR-agonist peptides such as N-formylmethionyl-leucyl-phenylalanine induced the migration and invasion of U-87MG cells, which was significantly decreased when the cells were treated with TFL. Conclusion: TFL inhibits the proliferation, migration and invasion of human glioblastoma U-87MG cells through decreasing the expression of FPR1. These findings provide valuable evidence for the development of antitumor drugs.

scholarly journals ZIPK is critical for the motility and contractility of VSMCs through the regulation of nonmuscle myosin II isoforms

2014 ◽  
Vol 306 (9) ◽  
pp. H1275-H1286 ◽  
Author(s):  
Satoshi Komatsu ◽  
Mitsuo Ikebe
Keyword(s):  
Protein Kinase ◽  
Collagen Gel ◽  
Collagen Matrix ◽  
Short Hairpin Rna ◽  
Nonmuscle Myosin ◽  
Hairpin Rna ◽  
Interacting Protein ◽  
Collagen Gel Contraction ◽  
Zipper Interacting Protein Kinase ◽  
Short Hairpin

Migration of medial vascular smooth muscle cells (VSMCs) into the intimal layer contributes to pathological remodeling of the blood vessel in arterial hypertension and atherosclerosis. It is well established that reorganization of cytoskeletal networks is an essential component of cellular motile events. However, there is currently a lack of insight into the cellular characteristics of VSMC migration under three-dimensional environments. Here, we investigated the mechanisms of VSMC migration and remodeling using two different collagen matrix assays as in vitro models: migration of VSMCs within a collagen matrix for VSMC invasion and contraction of a collagen gel by VSMCs for VSMC remodeling and contraction. We found that nonmuscle myosin IIA (NMIIA) and nonmuscle myosin IIB (NMIIB) differentially contribute to the migratory capacity of VSMCs via NMII isoform-dependent cytoskeletal reorganization. Depletion of NMIIA by short hairpin RNA revealed a unique interplay between actomyosin and microtubules during VSMC migration. On the other hand, NMIIB was required for the structural maintenance of migrating VSMC. Interestingly, there was a significant difference between NMIIA and NMIIB knockdown in the VSMC migration but not in the VSMC-mediated collagen gel contraction. Furthermore, depletion of zipper-interacting protein kinase by short hairpin RNA resulted in an impairment of VSMC migration and a substantial decrease of VSMC-mediated collagen gel contraction. These results suggest that NMIIA and NMIIB uniquely control VSMC migration and may contribute to vascular remodeling, which are both regulated by zipper-interacting protein kinase.

Folate-linked lipoplexes for short hairpin RNA targeting claudin-3 delivery in ovarian cancer xenografts

2013 ◽  
Vol 172 (3) ◽  
pp. 679-689 ◽  
Author(s):  
Zhi-Yao He ◽  
Xia-Wei Wei ◽  
Min Luo ◽  
Shun-Tao Luo ◽  
Yang Yang ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Short Hairpin Rna ◽  
Hairpin Rna ◽  
Rna Targeting ◽  
Short Hairpin

scholarly journals Angiotensin II-Induced Protein Kinase D Activates the ATF/CREB Family of Transcription Factors and Promotes StAR mRNA Expression

Endocrinology ◽  
2014 ◽  
Vol 155 (7) ◽  
pp. 2524-2533 ◽  
Author(s):  
Lawrence O. Olala ◽  
Vivek Choudhary ◽  
Maribeth H. Johnson ◽  
Wendy B. Bollag
Keyword(s):  
Transcription Factors ◽  
Angiotensin Ii ◽  
Protein Kinase ◽  
Mrna Expression ◽  
Dominant Negative ◽  
Protein Kinase D ◽  
Dependent Manner ◽  
Aldosterone Production ◽  
Glomerulosa Cells ◽  
Constitutively Active

Aldosterone synthesis is initiated upon the transport of cholesterol from the outer to the inner mitochondrial membrane, where the cholesterol is hydrolyzed to pregnenolone. This process is the rate-limiting step in acute aldosterone production and is mediated by the steroidogenic acute regulatory (StAR) protein. We have previously shown that angiotensin II (AngII) activation of the serine/threonine protein kinase D (PKD) promotes acute aldosterone production in bovine adrenal glomerulosa cells, but the mechanism remains unclear. Thus, the purpose of this study was to determine the downstream signaling effectors of AngII-stimulated PKD activity. Our results demonstrate that overexpression of the constitutively active serine-to-glutamate PKD mutant enhances, whereas the dominant-negative serine-to-alanine PKD mutant inhibits, AngII-induced StAR mRNA expression relative to the vector control. PKD has been shown to phosphorylate members of the activating transcription factor (ATF)/cAMP response element binding protein (CREB) family of leucine zipper transcription factors, which have been shown previously to bind the StAR proximal promoter and induce StAR mRNA expression. In primary glomerulosa cells, AngII induces ATF-2 and CREB phosphorylation in a time-dependent manner. Furthermore, overexpression of the constitutively active PKD mutant enhances the AngII-elicited phosphorylation of ATF-2 and CREB, and the dominant-negative mutant inhibits this response. Furthermore, the constitutively active PKD mutant increases the binding of phosphorylated CREB to the StAR promoter. Thus, these data provide insight into the previously reported role of PKD in AngII-induced acute aldosterone production, providing a mechanism by which PKD may be mediating steroidogenesis in primary bovine adrenal glomerulosa cells.

Sign in / Sign up

Export Citation Format

Share Document