Enhancer-promoter communication is fundamental to the spatial and temporal control of gene expression. Cohesin-mediated loop extrusion has long been considered a major structural mechanism that brings distal regulatory elements into proximity with their target promoters. Recent findings from Aboreden et al. refine this view by showing that depletion of Nipped-B-like protein (NIPBL), a key regulator of cohesin loading and loop extrusion, markedly disrupts architectural chromatin loops, whereas many cis-regulatory contacts and broad post-mitotic transcriptional reactivation are only modestly affected. These observations suggest that loop extrusion is important, but not sufficient, for explaining productive regulatory communication. In this Comment, we discuss how transcriptional condensate-like assemblies may provide an additional biochemical and kinetic layer that helps convert regulatory proximity into transcriptional output. By locally enriching transcription factors, coactivators, mediator and RNA polymerase II(Pol II) around active loci, such regulatory hubs may stabilize productive enhancer-promoter encounters and modulate transcriptional activity. We further propose that transcriptional bursting provides a useful framework for understanding this conversion, because gene expression can be decomposed into burst frequency, burst duration and burst size. Integrating chromatin architecture, condensate organization and bursting dynamics may therefore provide a more complete view of how enhancer-promoter communication is re-established after mitosis and how regulatory proximity is converted into transcriptional output through mechanisms beyond loop extrusion.

Objective To explore the performance of mobile health platform for standardized management of pregnant women with gestational diabetes mellitus(GDM). Methods A randomized controlled trial was conducted,in which 295 women with GDM were randomized into two groups(traditional management group and mobile health management group)by a computer-generated sequence.The traditional management group accepted standardized GDM management,and the mobile health management group was supplemented by mobile health management based on the standardized management.The glycemic control rate and the incidences of low birth weight,macrosomia,preterm birth,premature rupture of membranes,postpartum hemorrhage after cesarean section,neonatal asphyxia,malformation,and admission to the neonatal intensive care unit were compared between the two groups. Results The glycemic control rate in mobile health management group was significantly higher than that in the traditional management group [(67.22±22.76)%
Cesarean Section ; Diabetes, Gestational/therapy* ; Female ; Fetal Macrosomia ; Humans ; Infant, Newborn ; Pregnancy ; Pregnancy Outcome ; Premature Birth ; Telemedicine

In this study, citrate synthase gene(CIT2), and malate synthase gene(MLS1) were successfully knocked out in β-amyrin-producing yeast cells by using CRISPR/CAS9. The promoter of phosphoglucose isomerase gene(PGI1) was replaced by that of cytochrome c oxidase subunit Ⅶa(Cox9)to weaken its expression, aiming to channel more carbon flux into the NADPH-producing pathway. The fermentation results showed that CIT2 deletion had no effect on the β-amyrin production. Compared with the control strain, the production of β-amyrin was increased by 1.85 times after deleting MLS1, reaching into 3.3 mg·L~(-1). By replacing the promoter of PGI1, the β-amyrin yield was 3.75 times higher than that of the control strain, reaching up to 6.7 mg·L~(-1). This study successfully knocked out the CITT2 and MLS1 genes and weakened the PGI1 gene by using CRISPR/CAS9, which directly influenced the production of β-amyrin and provided some reference for the the metabolic engineering of triterpernoid producing strain.
Ethanol ; Fermentation ; Metabolic Engineering ; Saccharomyces cerevisiae ; genetics

In this study, the synthetic pathway of β-amyrin was constructed in the pre-constructed Saccharomyces cerevisiae chassis strain Y0 by introducing β-amyrin synthase from Glycyrrhiza uralensis, resulting strain Y1-C20-6, which successfully produced β-amyrin up to 5.97 mg·L~(-1). Then, the mevalonate pyrophosphate decarboxylase gene(ERG19), mevalonate kinase gene(ERG12), 3-hydroxy-3-methylglutaryl-CoA synthase gene(ERG13), phosphomevalonate kinase gene(ERG8) and IPP isomerase gene(IDI1)were overexpressed to promoted the metabolic fluxto the direction of β-amyrin synthesis for further improving β-amyrin production, resulting the strain Y2-C2-4 which produced β-amyrin of 10.3 mg·L~(-1)under the shake flask fermentation condition. This is 100% higher than that of strain Y1-C20-6, illustrating the positive effect of the metabolic engineering strategy applied in this study. The titer of β-amyrin was further improved up to 157.4 mg·L~(-1) in the fed-batch fermentation, which was almost 26 fold of that produced by strain Y1-C20-6. This study not only laid the foundation for the biosynthesis of β-amyrin but also provided a favorable chassis strain for elucidation of cytochrome oxidases and glycosyltransferases of β-amyrin-based triterpenoids.
Fermentation ; Glycyrrhiza uralensis ; enzymology ; genetics ; Industrial Microbiology ; Intramolecular Transferases ; genetics ; Metabolic Engineering ; Oleanolic Acid ; analogs & derivatives ; biosynthesis ; Saccharomyces cerevisiae ; metabolism

OBJECTIVEInvestigations were carried out to understand the effect of 50 Hz power frequency magnetic field on microfilament assembly of human amniotic cells and on expression of actin and epidermal growth factor receptor.

METHODSHuman amnion FL cells were exposed to 0.1, 0.2, 0.3, 0.4, 0.5 mT power frequency magnetic field for 30 minutes. Microfilaments were marked using Phalloidin-TRITC, and then were observed under a fluorescence microscope. An optical method was used to detect the relative content of microfilament in cells. A scanning electron microscope was used to detect the cell shape. The content of actin and epidermal growth factor receptor in the preparation of the detergent-insoluble cytoskeleton were measured by western-blotting to analyse the potential mechanism of the change induced by magnetic field.

RESULTSIntracellular stress fibers were found to decrease after exposing cells to a 0.2 mT power frequency magnetic field for 30 minutes. New microfilament and filopodia bundles appeared at the cell periphery after exposure, but the detected total F-actin content per cell was not significantly changed, detected by a F-actin-specific dye. The change in the amount of microfilaments caused by the field could be recovered 2 hours later when the field was withdrawn. The mean height of microfilament cytoskeleton decreased from (12.37 +/- 1.28) microm to (9.97 +/- 0.38) microm (t = 6.96, P > 0.05) after exposure using a confocal microscope. The cell shapes became more flat and lamellipodia appeared after exposure observed by a scanning electron microscope. By using Western blotting method, the intracellular contents of epidermal growth factor receptor and of actin in the preparation of the detergent-insoluble cytoskeleton which are associated with high-affinity epidermal growth factor receptors, increased about (31.2 +/- 4.1)% (t = 17.10, P < 0.05) and (16.8 +/- 2.3)% (t = 16.68, P < 0.05) respectively, compared with that of the control.

CONCLUSIONThese results suggest that a short time exposure to a 0.2 mT power frequency magnetic field induces re-organization of microfilament in human amnion FL cells. These changes could be recovered by field withdraw and may have something with the clustering of epidermal growth factor receptors induced by magnetic field.

Actin Cytoskeleton ; metabolism ; Amnion ; cytology ; radiation effects ; Cell Line ; Cell Movement ; Cytoskeleton ; metabolism ; radiation effects ; Electromagnetic Fields ; Humans ; Receptor, Epidermal Growth Factor ; metabolism ; Signal Transduction