Biomedical subjects

Radhika Reddy

Publications and source records attributed to Radhika Reddy.

4 recordsLinked to original sources

PubMed2026

The Gabriella Miller Kids First Data Resource for genomic research in pediatric cancer and congenital anomalies.

Nine-year-old brain tumor patient Gabriella Miller challenged members of Congress to "stop talking and start doing" when providing federal funding for research into cures for pediatric cancer and congenital anomalies. Though she ultimately lost her life to that cancer, her advocacy efforts resulted in the 2014 Gabriella Miller Kids First Research Act, launching the Gabriella Miller Kids First Pediatric Research Program at the National Institutes of Health (NIH). The overarching goal of the Gabriella Miller Kids First Pediatric Research Program is to help researchers uncover new insights into the biology of childhood cancer and congenital anomalies. Following the signing of the Gabriella Miller Kids First Research Act 2.0 in January 2025, the program has been extended at NIH through 2028 to advance the groundwork laid in the program's first ten years. The Gabriella Miller Kids First Data Resource Center has since honored her legacy by building a comprehensive data resource for genomic research into pediatric conditions. Data from more than 30,000 participants annotated with demographic and clinical information related to their diagnoses have been released for secondary research and analysis using the center's web-based platforms. This paper analyzes the outcomes of the initiative and highlights breakthroughs made by the larger research community resulting from the availability of this data resource. We explore the future expansion of the data resource to include new modalities and tools for supporting life-saving research for children like Gabriella Miller.

Humans↗

PubMed2003

Narp and NP1 form heterocomplexes that function in developmental and activity-dependent synaptic plasticity.

Narp is a neuronal immediate early gene that plays a role in excitatory synaptogenesis. Here, we report that native Narp in brain is part of a pentraxin complex that includes NP1. These proteins are covalently linked by disulfide bonds into highly organized complexes, and their relative ratio in the complex is dynamically dependent upon the neuron's activity history and developmental stage. Complex formation is dependent on their distinct N-terminal coiled-coil domains, while their closely homologous C-terminal pentraxin domains mediate association with AMPA-type glutamate receptors. Narp is substantially more effective in assays of cell surface cluster formation, coclustering of AMPA receptors, and excitatory synaptogenesis, yet their combined expression results in supraadditive effects. These studies support a model in which Narp can regulate the latent synaptogenic activity of NP1 by forming mixed pentraxin assemblies. This mechanism appears to contribute to both activity-independent and activity-dependent excitatory synaptogenesis.

Amino Acid Sequence↗

PubMed2002

Prominent Narp expression in projection pathways and terminal fields.

Narp (neuronal activity regulated pentraxin) is a secreted immediate early gene product that is induced by synaptic activity. Recent studies have indicated that Narp may be an extracellular aggregating factor for AMPA receptors. Immunohistochemical studies have revealed prominent expression of Narp in the mossy fiber pathway of the dentate gyrus, suggesting it may be released pre-synaptically. However, in vitro studies using recombinant Narp indicate that Narp may act when expressed by either pre- or post-synaptic elements. To help define Narp's mode of action, we have examined its localization in the habenula-interpeduncular pathway which also displays robust Narp expression. Focusing on this pathway as well as hippocampal and cortical Narp expression, we found prominent Narp staining in projection pathways and terminal fields. In contrast, Narp expression in dendrites was minimal in these neuronal populations. These findings indicate that, under physiological conditions, Narp is targeted to the synapse from pre- rather than post-synaptic elements. Our results also suggest that future studies focusing on these projection pathways that express high levels of Narp, in vivo, may help to understand the regulation and function of endogenous Narp.

Animals↗

PubMed2002

Selective expression of Narp, a secreted neuronal pentraxin, in orexin neurons.

Recent studies have provided compelling evidence demonstrating that orexin (also known as hypocretin) neurons play a central role in the pathophysiology of narcolepsy. However, targeted deletion of orexin does not fully mimic the functional deficits induced by selective ablation of these neurons; implying that other secreted signaling molecules expressed in these neurons mediate key aspects of their function. In this study, we demonstrate that orexin neurons display robust expression of neuronal activity-regulated pentraxin (Narp), a secreted neuronal pentraxin, implicated in regulating clustering of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors. Furthermore, we have found that hypothalamic melanin-concentrating hormone (MCH) neurons, which form a peptidergic pathway thought to oppose the effects of the orexin system, express another neuronal pentraxin, NP1. Thus, these findings suggest that these pathways utilize neuronal pentraxins, in addition to neuropeptides, as synaptic signaling molecules.

Animals↗