scholarly journals In vitro translation of the intermediate filament proteins desmin and vimentin.

1981 ◽  
Vol 1 (4) ◽  
pp. 303-309 ◽  
Author(s):  
C M O'Connor ◽  
D J Asai ◽  
C N Flytzanis ◽  
E Lazarides

Polyadenylated ribonucleic acid (RNA) was isolated from chicken skeletal and smooth muscle and translated in a cell-free rabbit reticulocyte system. Both types of muscle tissue contain messenger RNAs that code for the intermediate filament proteins desmin and vimentin, and the relative concentrations of the two translation products reflect the prevalence of the two proteins in vivo. Desmin synthesis represents a greater proportion of the total protein synthesis from smooth muscle RNA than from skeletal muscle RNA, whereas the converse is true of vimentin synthesis. Fractionation of the RNA on formamide-containing sucrose gradients before translation indicates that the desmin messenger RNA is larger than the vimentin messenger RNA and contains an extensive noncoding segment. The desmin and vimentin messages code predominantly for the non-phosphorylated forms of desmin and vimentin. However, the ratio of phosphorylated to unphosphorylated forms of the proteins could be increased by adding cyclic adenosine monophosphate-dependent kinase activity to the translation mixtures. These results suggest that desmin and vimentin are each synthesized from a single messenger RNA species and that posttranslational phosphorylation generates the additional isoelectric variants of each which are observed in vivo.

1981 ◽  
Vol 1 (4) ◽  
pp. 303-309
Author(s):  
C M O'Connor ◽  
D J Asai ◽  
C N Flytzanis ◽  
E Lazarides

Polyadenylated ribonucleic acid (RNA) was isolated from chicken skeletal and smooth muscle and translated in a cell-free rabbit reticulocyte system. Both types of muscle tissue contain messenger RNAs that code for the intermediate filament proteins desmin and vimentin, and the relative concentrations of the two translation products reflect the prevalence of the two proteins in vivo. Desmin synthesis represents a greater proportion of the total protein synthesis from smooth muscle RNA than from skeletal muscle RNA, whereas the converse is true of vimentin synthesis. Fractionation of the RNA on formamide-containing sucrose gradients before translation indicates that the desmin messenger RNA is larger than the vimentin messenger RNA and contains an extensive noncoding segment. The desmin and vimentin messages code predominantly for the non-phosphorylated forms of desmin and vimentin. However, the ratio of phosphorylated to unphosphorylated forms of the proteins could be increased by adding cyclic adenosine monophosphate-dependent kinase activity to the translation mixtures. These results suggest that desmin and vimentin are each synthesized from a single messenger RNA species and that posttranslational phosphorylation generates the additional isoelectric variants of each which are observed in vivo.


Blood ◽  
2000 ◽  
Vol 96 (9) ◽  
pp. 3215-3223 ◽  
Author(s):  
Sandra Verploegen ◽  
Jan-Willem J. Lammers ◽  
Leo Koenderman ◽  
Paul J. Coffer

Human granulocytes are characterized by a variety of specific effector functions involved in host defense. Several widely expressed protein kinases have been implicated in the regulation of these effector functions. A polymerase chain reaction–based strategy was used to identify novel granulocyte-specific kinases. A novel protein kinase complementary DNA with an open reading frame of 357 amino acids was identified with homology to calcium-calmodulin–dependent kinase I (CaMKI). This has been termed CaMKI-like kinase (CKLiK). Analysis of CKLiK messenger RNA (mRNA) expression in hematopoietic cells demonstrated an almost exclusive expression in human polymorphonuclear leukocytes (PMN). Up-regulation of CKLiK mRNA occurs during neutrophilic differentiation of CD34+ stem cells. CKLiK kinase activity was dependent on Ca++ and calmodulin as analyzed by in vitro phosphorylation of cyclic adenosine monophosphate responsive element modulator (CREM). Furthermore, CKLiK- transfected cells treated with ionomycin demonstrated an induction of CRE- binding protein (CREB) transcriptional activity compared to control cells. Additionally, CaMK-kinaseα enhanced CKLiK activity. In vivo activation of CKLiK was shown by addition of interleukin (IL)-8 to a myeloid cell line stably expressing CKLiK. Furthermore inducible activation of CKLiK was sufficient to induce extracellular signal-related kinase (ERK) mitogen-activated protein (MAP) kinase activity. These data identify a novel Ca++/calmodulin-dependent PMN- specific kinase that may play a role in Ca++-mediated regulation of human granulocyte functions.


Blood ◽  
2000 ◽  
Vol 96 (9) ◽  
pp. 3215-3223 ◽  
Author(s):  
Sandra Verploegen ◽  
Jan-Willem J. Lammers ◽  
Leo Koenderman ◽  
Paul J. Coffer

Abstract Human granulocytes are characterized by a variety of specific effector functions involved in host defense. Several widely expressed protein kinases have been implicated in the regulation of these effector functions. A polymerase chain reaction–based strategy was used to identify novel granulocyte-specific kinases. A novel protein kinase complementary DNA with an open reading frame of 357 amino acids was identified with homology to calcium-calmodulin–dependent kinase I (CaMKI). This has been termed CaMKI-like kinase (CKLiK). Analysis of CKLiK messenger RNA (mRNA) expression in hematopoietic cells demonstrated an almost exclusive expression in human polymorphonuclear leukocytes (PMN). Up-regulation of CKLiK mRNA occurs during neutrophilic differentiation of CD34+ stem cells. CKLiK kinase activity was dependent on Ca++ and calmodulin as analyzed by in vitro phosphorylation of cyclic adenosine monophosphate responsive element modulator (CREM). Furthermore, CKLiK- transfected cells treated with ionomycin demonstrated an induction of CRE- binding protein (CREB) transcriptional activity compared to control cells. Additionally, CaMK-kinaseα enhanced CKLiK activity. In vivo activation of CKLiK was shown by addition of interleukin (IL)-8 to a myeloid cell line stably expressing CKLiK. Furthermore inducible activation of CKLiK was sufficient to induce extracellular signal-related kinase (ERK) mitogen-activated protein (MAP) kinase activity. These data identify a novel Ca++/calmodulin-dependent PMN- specific kinase that may play a role in Ca++-mediated regulation of human granulocyte functions.


2021 ◽  
Author(s):  
Tianfei Fan ◽  
Yangfeng Hou ◽  
Weipeng Ge ◽  
Tianhui Fan ◽  
Wenjun Guo ◽  
...  

Abstract Hypertension is a common chronic disease, which leads to cardiovascular and cerebrovascular diseases, and its prevalence is increasing. Cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) pathway participates in multiple cardiovascular diseases. Phosphodiesterase (PDE) 4 has been shown to regulate PKA activity via cAMP specific hydrolysis. However, whether PDE4-cAMP-PKA pathway influences hypertension remains unknown. Herein, we reveal that PDE4D (one of PDE4 isoforms) expression is upregulated in angiotensin II (Ang II)-induced hypertensive mice aortas. Furthermore, knockout of Pde4d in mouse smooth muscle cells (SMCs) attenuate Ang II-induced high BP, arterial wall media thickening, vascular fibrosis and vasocontraction. Upon further investigation, we find that Pde4d deficiency activate PKA-AMP-activated protein kinase signaling pathway to inhibit myosin phosphatase targeting subunit 1-myosin light chain phosphorylation, relieving Ang II-induced SMC contraction in vitro and in vivo. These results indicate that PDE4D may be a potential target for hypertension therapy.


2000 ◽  
Vol 113 (13) ◽  
pp. 2471-2483 ◽  
Author(s):  
I. Hofmann ◽  
C. Mertens ◽  
M. Brettel ◽  
V. Nimmrich ◽  
M. Schnolzer ◽  
...  

Plakophilin 1 and 2 (PKP1, PKP2) are members of the arm-repeat protein family. They are both constitutively expressed in most vertebrate cells, in two splice forms named a and b, and display a remarkable dual location: they occur in the nuclei of cells and, in epithelial cells, at the plasma membrane within the desmosomal plaques. We have shown by solid phase-binding assays that both PKP1a and PKP2a bind to intermediate filament (IF) proteins, in particular to cytokeratins (CKs) from epidermal as well as simple epithelial cells and, to some extent, to vimentin. In line with this we show that recombinant PKP1a binds strongly to IFs assembled in vitro from CKs 8/18, 5/14, vimentin or desmin and integrates them into thick (up to 120 nm in diameter) IF bundles extending for several microm. The basic amino-terminal, non-arm-repeat domain of PKP1a is necessary and sufficient for this specific interaction as shown by blot overlay and centrifugation experiments. In particular, the binding of PKP1a to IF proteins is saturable at an approximately equimolar ratio. In extracts from HaCaT cells, distinct soluble complexes containing PKP1a and desmoplakin I (DPI) have been identified by co-immunoprecipitation and sucrose density fractionation. The significance of these interactions of PKP1a with IF proteins on the one hand and desmoplakin on the other is discussed in relation to the fact that PKP1a is not bound - and does not bind - to extended IFs in vivo. We postulate that (1) effective cellular regulatory mechanisms exist that prevent plakophilins from unscheduled IF-binding, and (2) specific desmoplakin interactions with either PKP1, PKP2 or PKP3, or combinations thereof, are involved in the selective recruitment of plakophilins to the desmosomal plaques.


2015 ◽  
Vol 27 (1) ◽  
pp. 209
Author(s):  
T. Fanti ◽  
N. M. Ortega ◽  
R. Garaguso ◽  
M. J. Franco ◽  
C. Herrera ◽  
...  

In vitro embryo production systems (IVP) try to emulate and enhance molecular events that occur in in vivo reproductive systems in order to increase, not only the number of embryos generated, but also their quality. Despite advances, IVP processes are still inefficient compared with in vivo systems. Several studies have attributed this deficiency to a lack of oocyte competence due to spontaneous premature resumption of meiotic maturation in the oocyte following the removal from its follicular environment. Therefore, our objective was to increase oocyte competence avoiding premature resumption of meiosis by using cyclic adenosine monophosphate modulators. Cumulus-oocyte complexes (COC) were obtained from ovaries of slaughterhouses, washed, and randomly allocated in 2 culture systems. Oocytes in the control group (IVM) were cultured for a period of 24 h in basal medium TCM-199 with EGF (1 µg mL–1) supplemented with rhFSH (25 mIU mL–1). Oocytes in the biphasic in vitro maturation (b-IVM) group were cultured for 2 h in a basal medium supplemented with a phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX, 500 µM), and an activator of adenylate cyclase (forskolin, 100 µM). Subsequently, COC were washed and cultured in basal medium supplemented with cilostamide (20 µM) and rhFSH (25 mIU mL–1) for 24 h. Maturation rates were analysed and IVF was performed with a dose of 1 × 106 sperm cells mL–1 in IVF-SOF medium. The presumptive zygotes were cultured in continuous-single-culture medium (Irvine) supplemented with 8 mg mL–1 of BSA until they reached the blastocyst stage. No significant differences in maturation, cleavage, and cryotolerance were observed between b-IVM and IVM groups (P > 0.05; Table 1). This study showed that b-IVM produced a significant increase in IVP compared with the control (IVM) at Days 7 and 8 (P < 0.01). Blastocyst hatching rate was significant (P < 0.05) for both treatment and day of analysis. The b-IVM group yielded an increase of 10 and 7.5% at Days 7 and 8, respectively, of IVP. The biphasic maturation showed an improvement in quality regarding the control group, in the timing analysis of production, and hatching percentages, and these results show that the use of cyclic adenosine monophosphate modulators in the oocyte maturation process enhances oocyte competence, which is reflected in increased productivity and embryo quality. We propose this treatment as an alternative to the standard protocols currently used in IVP of bovine embryos. Table 1.Effect of treatment on maturation, cleavage, and cryotolerance


2014 ◽  
Vol 26 (1) ◽  
pp. 193
Author(s):  
R. Appeltant ◽  
J. Beek ◽  
D. Maes ◽  
A. Van Soom

When using modern maturation conditions for in vitro maturation, pig oocytes yield ~20% blastocysts only. One problem is that cumulus cells, which are normally connected with the immature oocyte by cellular projections penetrating through the zona pellucida and with the oolemma via gap junctions, are prematurely losing these connections after the cumulus–oocyte complex is removed from the follicle. The oocyte possesses a type 3 phosphodiesterase, which degrades 3′,5′-cyclic adenosine monophosphate (cAMP), and this activity is inhibited by supply of 3′,5′-cyclic guanosine monophosphate (cGMP) to the oocyte via the cumulus cells. Consequently, cAMP levels, which are typically high during early stages of oocyte maturation in vivo, decrease, leading to spontaneous nuclear maturation and oocytes of low developmental competence. Therefore, the maintenance of these cumulus-oocyte connections is important to keep cAMP high and the oocyte under meiotic arrest. One way to prevent this drop in cAMP is using N6, 2′-o-dibutyryladenosine 3′,5′-cyclic monophosphate sodium (dbcAMP) that causes an arrest at germinal vesicle (GV) stage II (Funahashi et al. 1997 Biol. Reprod. 57, 49–53). Another option is collecting the oocytes in a medium containing the phoshodiesterase inhibitor, IBMX. The present study investigated the influence of IBMX on the progression of the GV of the oocyte after collection, just before the start of the maturation procedure. The GV stage was defined according to Sun et al. (2004 Mol. Reprod. Dev. 69, 228–234). In parallel with the findings on dbcAMP, we hypothesised an arrest at GV II by the presence of IBMX during collection. One group of oocytes were collected in HEPES-buffered TALP without IBMX (n = 375) and another group in the same medium containing 0.5 mM IBMX (n = 586). An average incubation time of 140 min was applied in both groups, and 3 replicates were performed. The proportions of oocytes before or at GV II and beyond GV II were compared in both groups using logistic regression analysis. The proportion of oocytes was included as dependent variable and group (IBMX addition or not) as independent variable. Replicate was also included in the model. The proportion of oocytes before or at GV II was not statistically significant between the group without and the group with IBMX (59.2 v. 58.7% respectively; P > 0.05). In conclusion, the use of IBMX during oocyte collection did not influence the state of the germinal vesicle of the oocyte during collection, indicating that IBMX did not cause a meiotic arrest in the oocytes during collecting in vitro.


2021 ◽  
Author(s):  
Shih-Ya Tseng ◽  
Hsien-Yuan Chang ◽  
Yi-Heng Li ◽  
Ting-Hsing Chao

Abstract Background: Cilostazol is an antiplatelet agent with vasodilating effects that functions by increasing the intracellular concentration of cyclic adenosine monophosphate. However, the effect of cilostazol on adiponectin is still unclear. Purpose: We investigated the effects of cilostazol on adiponectin/adiponectin receptors and the Sirtuin 1 (SIRT1)/AMP-activated protein kinase (AMPK) signaling pathway to prevent high glucose (HG)-induced impairment of angiogenesis in vitro and in vivo. Methods and Results: Human umbilical vein endothelial cells (HUVECs) and human aortic smooth muscle cells (HASMCs) were cocultured in HG conditions. Adiponectin concentrations in the supernatant were significantly increased when HASMCs were treated with cilostazol but not significantly changed when only HUVECs were treated with cilostazol. Cilostazol treatment restored the expression of the adipoR1 and SIRT1 proteins and upregulated the phosphorylation of AMPKa1 in the HUVECs treated with HG but not adipoR2. Cilostazol prevented apoptosis and stimulated proliferation, chemotactic motility and capillary-like tube formation in HG-treated HUVECs through the adipoR1/AMPK/SIRT1 signaling pathway. In cilostazol-treated mice, recovery of the blood flow ratio after hindlimb ischemia and circulating CD34+CD45dim cells were significantly attenuated by adipoR1 knockdown but not adipoR2 knockdown. The expression of SIRT1, phosphorylation of AMPKa1/acetyl-CoA carboxylase and Akt/endothelial nitric oxide synthase in ischemic muscles were significantly attenuated by gene knockdown of adipoR1. Conclusions: Cilostazol prevents HG-induced endothelial dysfunction in vascular endothelial cells and enhances angiogenesis in hyperglycemic mice by upregulating the expression of adiponectin/adipoR1 and its SIRT1/AMPK downstream signaling pathway.


2019 ◽  
Vol 26 (12) ◽  
pp. 1626-1632 ◽  
Author(s):  
Hanh N. Cottrell ◽  
Venkataraman Deepak ◽  
Jessica B. Spencer ◽  
Neil Sidell ◽  
Augustine Rajakumar

Objective: Supraphysiologic estradiol (E2) levels associated with controlled ovarian hyperstimulation in high in vitro fertilization (IVF) responders may alter implantation and placentation and increase the risk of preeclampsia. Our hypothesis is that elevated E2 levels in vitro significantly alter endometrial decidualization, sFlt1, and HOXA10 expression. Methods: Human endometrial stromal cells were treated with a decidualization cocktail of medroxyprogesterone, cyclic adenosine monophosphate, and 3 concentrations of E2 10 nM (standard), 100 nM (intermediate), or 1000 nM E2 (high). Effects on sFlt1, prolactin (PRL), insulin-like growth factor binding protein 1 (IGFBP-1), vascular endothelial growth factor (VEGF), and HOXA10 were studied. Results: Prolactin, IGFBP-1, and VEGF significantly increased at all 3 E2 concentrations. While IGFBP-1 and VEGF did not change with increasing E2, PRL was less with high E2 (6.0 ng/mL ± 1.4 standard error of the mean) compared to standard (21.4 ± 3.2) and intermediate (19.8 ± 3.8). sFlt1 decrease was similar at all E2 concentrations. HOXA10 was lower at standard (10%) and intermediate (30%) as expected, but did not change with high E2. Conclusions: Supraphysiologic E2 levels associated with high IVF responders that exceed in vivo levels may impair in vitro endometrial decidualization. Although PRL did increase with high E2, the levels were, however, attenuated and 3.4-fold lower than standard and intermediate E2. sFlt1 was decreased under all 3 conditions with no differences between concentrations. Reduced HOXA10 was not observed with high E2. These findings suggest that elevated E2 levels in vitro may alter endometrial decidualization and subsequently affect implantation and placentation.


Author(s):  
Hao Yang ◽  
Yulong Zhao ◽  
Ning Chen ◽  
Yanpei Liu ◽  
Shaoyu Yang ◽  
...  

Abstract In plants, 3´,5´-cyclic adenosine monophosphate (cAMP) is an important second messenger with varied functions; however, only a few adenylyl cyclases (ACs) that synthesize cAMP have been identified. Moreover, the biological roles of ACs/cAMP in response to stress remain largely unclear. In this study, we used quantitative proteomics techniques to identify a maize heat-induced putative disease-resistance RPP13-like protein 3 (ZmRPP13-LK3), which has three conserved catalytic AC centres. The AC activity of ZmRPP13-LK3 was confirmed by in vitro enzyme activity analysis, in vivo RNAi experiments, and functional complementation in the E. coli cyaA mutant. ZmRPP13-LK3 is located in the mitochondria. The results of in vitro and in vivo experiments indicated that ZmRPP13-LK3 interacts with ZmABC2, a possible cAMP exporter. Under heat stress, the concentrations of ZmRPP13-LK3 and cAMP in the ABA-deficient mutant vp5 were significantly less than those in the wild-type, and treatment with ABA and an ABA inhibitor affected ZmRPP13-LK3 expression in the wild-type. Application of 8-Br-cAMP, a cAMP analogue, increased heat-induced expression of heat-shock proteins in wild-type plants and alleviated heat-activated oxidative stress. Taken together, our results indicate that ZmRPP13-LK3, a new AC, can catalyse ATP for the production of cAMP and may be involved in ABA-regulated heat resistance.


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