Abstract only
The absence of a nuclear compartment permits prokaryotic ribosomes to bind nascent RNAs to initiate translation before a transcript is completely synthesized. Transcription and ...translation are normally tightly coupled in prokaryotes (Archaea and Bacteria) and uncoupling translation from transcription serves as a regulatory signal, permitting premature transcription termination when translation fails or is inhibited. The resultant decrease in downstream gene expression, termed polarity, is a major regulatory pathway to ensure coordinated gene expression. While the importance and widespread use of polar repression is well documented, to date, the factor responsible for polarity in archaea cells has not been explicitly identified.
In bacteria, the transcription termination factor rho is responsible for polarity, but there are no rho homologues encoded in archaeal genomes. FttA (Factor that terminates transcription in Archaea), a recently identified archaeal termination factor, appears to potentially fulfill the requirements to direct polarity in archaea, but other factors may be responsible. Our primary objective, employing an unbiased genetic selection, is to identify the transcription termination factor(s) responsible for polar repression in Archaea.
We have established and will present our findings resultant from a three‐tiered genetic selection for spontaneous mutations that impact the efficiency of polar repression in archaeal cells. The selections were carried out in specialized strains of
Thermococcus kodakarensis
, a marine, hyperthermophilic archaeon with a facile genetic system and robust laboratory growth.
Briefly, genomic modifications were introduced to place a non‐essential gene with a premature translation stop codon directly upstream and within the same operon of a reporter or essential (selection) gene. In wide‐type strains, the early stop codon permits a polarity factor to recognize uncoupling of transcription and translation and terminate transcription before productive expression of the downstream essential gene. However, when the activity of a polarity factor(s) is hindered, these selective genes can be expressed at high levels. For selection, the final genes of the tryptophan and histidine synthesis pathway were chosen, constructing auxotrophic mutant strains which can only develop in the absence of tryptophan and histidine if there is some disruption in polarity‐ allowing them to become prototrophic. The spontaneous mutations resultant in reduced polar repression are easily identified through whole‐genome sequencing and we present evidence for roles of multiple factors in mediating polarity in archaeal cells.
Endothelial dysfunction results in chronic vascular inflammation, which is critical for the development of atherosclerotic diseases. Transcription factor Gata6 has been reported to regulate vascular ...endothelial cell activation and inflammation in vitro. Here, we aimed to explore the roles and mechanisms of endothelial Gata6 in atherogenesis.
Endothelial cell (EC) specific Gata6 deletion was generated in the ApoeKO hyperlipidemic atherosclerosis mouse model. Atherosclerotic lesion formation, endothelial inflammatory signaling, and endothelial-macrophage interaction were examined in vivo and in vitro by using cellular and molecular biological approaches. EC-GATA6 deletion mice exhibited a significant decrease in monocyte infiltration and atherosclerotic lesion compared to littermate control mice. Cytosine monophosphate kinase 2 (Cmpk2) was identified as a direct target gene of GATA6 and EC-GATA6 deletion decreased monocyte adherence, migration and pro-inflammatory macrophage foam cell formation through regulation of the CMPK2-Nlrp3 pathway. Endothelial target delivery of Cmpk2-shRNA by intercellular adhesion molecule 2 (Icam-2) promoter-driven AAV9 carrying the shRNA reversed the Gata6 upregulation mediated elevated Cmpk2 expression and further Nlrp3 activation and thus attenuated atherosclerosis. In addition, C–C motif chemokine ligand 5 (Ccl5) was also identified as a direct target gene of Gata6 to regulate monocyte adherence and migration influencing atherogenesis.
This study provides direct in vivo evidence of EC-GATA6 involvement in the regulation of Cmpk2-Nlrp3, as well as Ccl5, on monocyte adherence and migration in atherosclerosis development and advances our understanding of the in vivo mechanisms of atherosclerotic lesion development, and meanwhile provides opportunities for future therapeutic interventions.
•Elevated Gata6 expression in ECs of atherosclerotic lesions, and EC-Gata6 regulates the development of atherosclerosis.•EC-Gata6 regulates Cmpk2-Nlrp3 pathways resulting in monocyte recruitment and proinflammatory macrophage formation.•Icam-2 promoter driven AAV9 endothelial target delivery of Cmpk2-shRNA suppresses atherosclerotic lesion formation.
Background The endothelium is essential for maintaining vascular physiological homeostasis and the endothelial injury leads to the neointimal hyperplasia because of the excessive proliferation of ...vascular smooth muscle cells. Endothelial Foxp1 (forkhead box P1) has been shown to control endothelial cell (EC) proliferation and migration in vitro. However, whether EC-Foxp1 participates in neointimal formation in vivo is not clear. Our study aimed to investigate the roles and mechanisms of EC-Foxp1 in neointimal hyperplasia. Methods and Results The wire injury femoral artery neointimal hyperplasia model was performed in Foxp1 EC-specific loss-of-function and gain-of-function mice. EC-Foxp1 deletion mice displayed the increased neointimal formation through elevation of vascular smooth muscle cell proliferation and migration, and the reduction of EC proliferation hence reendothelialization after injury. In contrast, EC-Foxp1 overexpression inhibited the neointimal formation. EC-Foxp1 paracrine regulated vascular smooth muscle cell proliferation and migration via targeting matrix metalloproteinase-9. Also, EC-Foxp1 deletion impaired EC repair through reduction of EC proliferation via increasing cyclin dependent kinase inhibitor 1B expression. Delivery of cyclin dependent kinase inhibitor 1B-siRNA to ECs using RGD (Arg-Gly-Asp)-peptide magnetic nanoparticle normalized the EC-Foxp1 deletion-mediated impaired EC repair and attenuated the neointimal formation. EC-Foxp1 regulates matrix metalloproteinase-9/cyclin dependent kinase inhibitor 1B signaling pathway to control injury induced neointimal formation. Conclusions Our study reveals that targeting EC-Foxp1-matrix metalloproteinase-9/cyclin dependent kinase inhibitor 1B pathway might provide future novel therapeutic interventions for restenosis.
Key Points Foxp1 is a key transcriptional factor for the differentiation of intercalated cells in collecting ducts. Dmrt2 and Hmx2 act downstream of Foxp1 to control the differentiation of type A and ...type B intercalated cells, respectively. Foxp1 and Dmrt2 are essential for body acid–base balance regulation. Background Kidney collecting ducts comprise principal cells and intercalated cells, with intercalated cells playing a crucial role in kidney acid–base regulation through H + and HCO 3 − secretion. Despite its significance, the molecular mechanisms controlling intercalated cell development remain incompletely understood. Methods To investigate the specific role of Foxp1 in kidney tubular system, we specifically deleted Foxp1 expression in kidney distal nephrons and collecting ducts. We examined the effects of Foxp1 on intercalated cell differentiation and urine acidification. RNA sequencing and Chip-seq were used to identify Foxp1 target genes. To dissect the genetic network that regulates intercalated cell differentiation, Dmrt2 -deficient mice were generated to determine the role of Dmrt2 in intercalated cell differentiation. Foxp1 -deficient mice were crossed with Notch2 -deficient mice to dissect the relation between Foxp1 and Notch signaling. Results Foxp1 was selectively expressed in intercalated cells in collecting ducts. The absence of Foxp1 in kidney tubules led to the abolishment of intercalated cell differentiation in the collecting ducts, resulting in distal renal tubular acidosis. Foxp1 regulates the expression of Dmrt2 and Hmx2 , two genes encoding transcription factors specifically expressed in type A and type B intercalated cell cells, respectively. Further genetic analysis revealed that Dmrt2 was essential for type A intercalated cell differentiation, and Foxp1 was necessary downstream of Notch for the regulation of intercalated cell differentiation. Conclusions Foxp1 is required for the renal intercalated cell differentiation and participated in acid–base regulation. Foxp1 regulated downstream transcriptional factors, Dmrt2 and Hmx2, which were involved in the specification of distinct subsets of intercalated cells.
This study introduces a novel trifluoromethylating reagent, (bpy)Cu(O2CCF2SO2F)2, notable for not only its practical synthesis from cost-effective starting materials and scalability but also its ...nonhygroscopic nature. The reagent demonstrates high efficiency in facilitating trifluoromethylation reactions with various halogenated hydrocarbons, yielding products in good yields and exhibiting broad functional group compatibility. The development of (bpy)Cu(O2CCF2SO2F)2 represents an advancement in the field of organic synthesis, potentially serving as a valuable addition to the arsenal of existing trifluoromethylating agents.
This study introduces a novel trifluoromethylating reagent, (bpy)Cu(O2CCF2SO2F)2, notable for not only its practical synthesis from cost-effective starting materials and scalability but also its ...nonhygroscopic nature. The reagent demonstrates high efficiency in facilitating trifluoromethylation reactions with various halogenated hydrocarbons, yielding products in good yields and exhibiting broad functional group compatibility. The development of (bpy)Cu(O2CCF2SO2F)2 represents an advancement in the field of organic synthesis, potentially serving as a valuable addition to the arsenal of existing trifluoromethylating agents.This study introduces a novel trifluoromethylating reagent, (bpy)Cu(O2CCF2SO2F)2, notable for not only its practical synthesis from cost-effective starting materials and scalability but also its nonhygroscopic nature. The reagent demonstrates high efficiency in facilitating trifluoromethylation reactions with various halogenated hydrocarbons, yielding products in good yields and exhibiting broad functional group compatibility. The development of (bpy)Cu(O2CCF2SO2F)2 represents an advancement in the field of organic synthesis, potentially serving as a valuable addition to the arsenal of existing trifluoromethylating agents.
Summary of main observation and conclusion
A series of dinuclear rare‐earth metal alkyl complexes {μ‐η2:η1:η1‐3‐(LNCH)(CH2SiMe3)IndRE(CH2SiMe3)(THF)}2 (L1 = 2‐tBuC6H4, RE = Y, Gd, Dy, Er, Yb; L2 = ...2,4,6‐Me3C6H2, RE = Dy, Er; Ind = indolyl) and {μ‐η2:η1:η1‐3‐(LNCH2)IndRE(CH2SiMe3)(THF)}2 (L1, RE = Y, Dy, Er, Yb; L2, RE = Er, Yb) bearing 3‐arylamido functionalized indolyl ligands having diverse bonding modes with metal ions were synthesized either by the insertion reaction of the imino group to the RE—C bond or by the alkane elimination reaction. In the preparation of above complexes, rare‐earth metal alkyl complexes μ‐η5:η1:η1‐3‐(L2NCH)(CH2SiMe3)IndGd(CH2SiMe3)(THF)}2 with a μ‐η5:η1:η1 coordination mode to the gadolinium ion and {μ‐η3:η1:η1‐3‐(L2NCH2)IndDy(CH2SiMe3)(THF)}2 with a μ‐η3:η1:η1 coordination mode to the dysprosium ion were unexpectedly isolated. The reactions of 3‐(L2N=CH)Ind with Er(CH2SiMe3)3(THF)2 at room temperature, generated a tetranuclear imino‐indolyl erbium intermediate {μ‐η1:η1‐3‐(L2N=CH)IndEr(CH2SiMe3)2(THF)}4, which can transform into the amido functionalized indolyl erbium complex in hot toluene. Moreover, the reactivities of the newly synthesized ytterbium complex with N‐heterocyclic compounds were investigated, affording the corresponding products of the mixed pyridyl‐indolyl, imidazolyl‐indolyl, and ortho‐metalated complexes. The yttrium complexes showed a high regioselectivity and steroselectivity for the isoprene polymerization with 1,4‐trans selectivity up to 91.7% and 1,4‐cis selectivity up to 96.1% in the presence of cocatalysts, respectively.
A series of dinuclear rare‐earth metal alkyl complexes bearing 3‐arylamido indolyl ligands in different bonding modes with the metal ions were synthesized through two different pathways. These well‐characterized complexes exhibited a high activity towards N‐heterocyclic compounds and a good regioselectivity and steroselectivity for isoprene polymerization.
To compare the early analgesic effects and the impact on knee joint function recovery after unicompartmental knee arthroplasty (UKA) between single adductor canal block (SACB) and continuous adductor ...canal block (CACB) combined with local infiltration anesthesia (LIA) using a prospective study.
The patients with knee osteoarthritis admitted between April 2022 and December 2023 were enrolled as a subject. Among them, 60 patients met the selection criteria and were enrolled in the study. They were randomly assigned to the SACB group or CACB group in a ratio of 1:1 using a random number table method. There was no significant difference between the two groups (
>0.05) in terms of age, gender, height, body mass, body mass index, affected side, and preoperative resting visual analogue scale (VAS) score and active VAS score, Oxford knee score (OKS), and American Hospital of Special Surgery (HSS) score. All patients received multimodal analgesia management using LIA combined with SACB or CACB. The operation time, pai
► High-quality Ce3+ and Eu3+ co-doped YVO4 crystals were grown by the Czochralski method. ► The absorption spectra of crystals have been measured. ► The properties of spectra and energy transfer ...mechanism have been investigated. ► Ce and Eu co-doped YVO4 crystal can be potential phosphors for white LED.
High-quality Ce3+ and Eu3+ co-doped YVO4 crystals were grown by the Czochralski method in a medium frequency induction furnace. The X-ray Diffraction (XRD) patterns revealed that they were tetragonal crystals and no changes in the crystalline phases were observed after doping. The luminescence of YVO4: Ce3+ and YVO4: Ce3+/Eu3+ crystals were measured at room temperature. Both YVO4: Ce3+ and YVO4: Ce3+/Eu3+ crystals can be excited at 325nm: the former emitted blue light while the latter emitted red light. This phenomenon can be explained by the V–O charge transfer transitions. Particularly, the mechanisms of Photoluminescence (PL) and Photoluminescence Excitation (PLE) of YVO4: Ce3+ and YVO4: Ce3+/Eu3+ crystals have been thoroughly investigated in this work. The Commission International Eclairage (CIE) coordinates were also calculated for these crystals. The calculated CIE coordinates indicated that the YVO4: Ce3+/Eu3+ crystal prepared in this work, when excited at 397nm, could be a promising material for white light-emitting diodes.
