Iron homeostasis in animal cells is controlled post-transcriptionally by the iron regulatory proteins IRP1 and IRP2. IRP1 can assume two different functions in the cell, depending on conditions. During iron scarcity or oxidative stress, IRP1 binds to mRNA stem-loop structures called iron responsive elements (IREs) to modulate the translation of iron metabolism genes. In iron-rich conditions, IRP1 binds an iron-sulfur cluster to function as a cytosolic aconitase. This functional duality of IRP1 connects the translational control of iron metabolizing proteins to cellular iron levels. The recently determined structures of IRP1 in both functional states reveal the large-scale conformational changes required for these mutually exclusive roles, providing new insights into the mechanisms of IRP1 interconversion and ligand binding.
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http://dx.doi.org/10.1016/j.sbi.2007.12.010 | DOI Listing |
Math Program
February 2024
Department of Automatic Control, Lund University, Lund, Sweden.
We present a methodology for establishing the existence of quadratic Lyapunov inequalities for a wide range of first-order methods used to solve convex optimization problems. In particular, we consider (i) classes of optimization problems of finite-sum form with (possibly strongly) convex and possibly smooth functional components, (ii) first-order methods that can be written as a linear system on state-space form in feedback interconnection with the subdifferentials of the functional components of the objective function, and (iii) quadratic Lyapunov inequalities that can be used to draw convergence conclusions. We present a necessary and sufficient condition for the existence of a quadratic Lyapunov inequality within a predefined class of Lyapunov inequalities, which amounts to solving a small-sized semidefinite program.
View Article and Find Full Text PDFGen Physiol Biophys
January 2025
Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia.
Senescence, a crucial yet paradoxical phenomenon in cellular biology, acts as a barrier against cancer progression while simultaneously promoting aging and age-related pathologies. This duality underlines the importance of precise monitoring of senescence response, especially with regard to the proposed use of drugs selectively removing senescent cells. In particular, little is known about the role of senescence in neurons and in neurodegenerative diseases.
View Article and Find Full Text PDFJ Immunother Cancer
January 2025
Medical Oncology, Sarah Cannon Research Institute, Nashville, Tennessee, USA.
Background: SL-172154 is a hexameric fusion protein adjoining the extracellular domain of SIRPα to the extracellular domain of CD40L via an inert IgG-derived Fc domain. In preclinical studies, a murine equivalent SIRPα-Fc-CD40L fusion protein provided superior antitumor immunity in comparison to CD47- and CD40-targeted antibodies. A first-in-human phase I trial of SL-172154 was conducted in patients with platinum-resistant ovarian cancer.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
School of Basic Medical Sciences, Kunming Medical University, Kunming 650500, Yunnan, China. Electronic address:
Most Kunitz inhibitors exhibit serine protease inhibitory activity, but limited information is available on the regulation of platelet function. Herein, we report the purification and characterization of a novel single Kunitz domain inhibitor (Sibanin) from the salivary glands of the black fly Simulium bannaense. Recombinant Sibanin prolonged activated partial thromboplastin time and prothrombin time, and exhibited high-affinity binding to FXa and elastase with a KD of 5.
View Article and Find Full Text PDFCancers (Basel)
December 2024
Division of Hematology/Oncology, Department of Internal Medicine, University of California Davis School of Medicine, University of California Davis Comprehensive Cancer Center, Sacramento, CA 95817, USA.
Patient-centered precision oncology strives to deliver individualized cancer care. In lung cancer, preclinical models and technological innovations have become critical in advancing this approach. Preclinical models enable deeper insights into tumor biology and enhance the selection of appropriate systemic therapies across chemotherapy, targeted therapies, immunotherapies, antibody-drug conjugates, and emerging investigational treatments.
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