Early embryos must rapidly generate large numbers of cells to form an organism. Many species accomplish this through a series of rapid, reductive, and transcriptionally silent cleavage divisions. Previous work has demonstrated that the number of divisions before both cell cycle elongation and zygotic genome activation (ZGA) is regulated by the ratio of nuclear content to cytoplasm (N/C). To understand how the N/C ratio affects the timing of ZGA, we directly assayed the behavior of several previously identified N/C ratio-dependent genes using the MS2-MCP reporter system in living embryos with altered ploidy and cell cycle durations. For every gene that we examined, we found that nascent RNA output per cycle is delayed in haploid embryos. Moreover, we found that the N/C ratio influences transcription through three overlapping modes of action. For some genes (, , and ), the effect of ploidy can be primarily attributed to changes in cell cycle duration. However, additional N/C ratio-mediated mechanisms contribute significantly to transcription delays for other genes. For and the kinetics of transcription activation are significantly disrupted in haploids, while for and , the N/C ratio controls the probability of transcription initiation. Our data demonstrate that the regulatory elements of N/C ratio-dependent genes respond directly to the N/C ratio through multiple modes of regulation.
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http://dx.doi.org/10.1073/pnas.2010210118 | DOI Listing |
Int J Mol Sci
January 2025
Baylor University Medical Center, Texas Oncology, Dallas, TX 75246, USA.
Clinical T3 (cT3) breast cancer (BC) presents a challenge for achieving cosmetically acceptable breast conservation, and neoadjuvant chemotherapy (NAC) is commonly used for cytoreduction in these high-risk cancers. MammaPrint risk-of-recurrence and BluePrint molecular subtyping genomic signatures have demonstrated high accuracy in predicting chemotherapy benefits. Here, we examined the utility of MammaPrint/BluePrint for predicting pathological Complete Response (pCR) rates to NAC among 404 patients diagnosed with cT3 early-stage BC.
View Article and Find Full Text PDFSmall
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
Nitrogen doping emerges as a potent approach to enhance the oxidase-like activity of carbon nanozymes. However, the unclear knowledge of the active nitrogen species within nitrogen-doped carbon nanozymes hinders the advancement of high-performance carbon nanozymes. Herein, a group of nitrogen-doped carbon (N/C) nanozymes with controllable nitrogen dopants are successfully synthesized via a dicyandiamide-assisted pyrolysis method.
View Article and Find Full Text PDFFront Child Adolesc Psychiatry
May 2024
Department of Psychiatry & Behavioral Sciences, School of Medicine, Duke University, Durham, NC, United States.
Objective: The aim of our study was to delineate the differences in demographics, comorbidities, and hospital outcomes by eating disorder types in adolescents and transitional-age youth (15-26 years), and measure the association with psychiatric comorbidities.
Methods: We conducted a cross-sectional study using the nationwide inpatient sample (2018-2019) and included 7,435 inpatients (age 12-24 years) with a primary diagnosis of eating disorders: anorexia nervosa (AN, 71.7%), bulimia nervosa (BN, 4.
Circ Cardiovasc Imaging
January 2025
Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC. (P.S., C.H., G.B., A.H., S.H.S., P.S.D., M.A.D.).
Background: Patients with abnormal (positive) exercise electrocardiography, but normal stress echocardiography (+ECG/-Echo), have an increased risk of adverse cardiovascular events compared with patients with a normal (negative) ECG and a normal stress Echo (-ECG/-Echo). However, it is unclear if +ECG/-Echo discordance is associated with a greater burden of subclinical coronary atherosclerosis.
Methods: Project Baseline Health Study participants who underwent a stress Echo and coronary artery calcium (CAC) scan were stratified by stress Echo result: -ECG/-Echo or +ECG/-Echo.
Sci Rep
January 2025
Northwest Oilfield Company, SINOPEC, Ürümqi, 830011, China.
Deep oil reservoirs are becoming increasingly significant fields of hydrocarbon exploration in recent decades. Hydrothermal fluid flow is deemed as a potentially crucial factor affecting the occurrence of deep oil reservoirs, such as enhancing porosity/permeability of reservoirs, accelerating oil generation and thermal cracking, and modifying organic properties of crude oils. Understanding the interplay between hydrothermal fluids and crude oils would provide useful constraints for reconstructing hydrocarbon accumulation processes and predicting the distribution patterns of crude oils.
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