Search NASA⌕ Search

SEARCH · Search NASA

Results for “HORMONE”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

Altered cytokine production by specific human peripheral blood cell subsets immediately following space flight

In this study, flow cytometry was used to positively identify the specific lymphocyte subsets exhibiting space flight-induced alterations in cytokine production. Whole blood samples were collected from 27 astronauts at three points (one preflight, two postflight) surrounding four space shuttle missions. Assays performed included serum/urine stress hormones, white blood cell (WBC) phenotyping, and intracellular cytokine production following mitogenic stimulation. Absolute levels of peripheral granulocytes were significantly elevated following space flight, but the levels of circulating lymphocytes and monocytes were unchanged. Lymphocyte subset analysis demonstrated a decreased percentage of T cells, whereas percentages of B cells and natural killer (NK) cells remained unchanged after flight. Nearly all the astronauts exhibited an increased CD4/CD8 T cell ratio. Assessment of naive (CD45RA+) vs. memory (CD45RO+) CD4+ T cell subsets was ambiguous, and subjects tended to group within specific missions. Although no significant trend was seen in absolute monocyte levels, a significant decrease in the percentage of the CD14+ CD16+ monocytes was seen following space flight in all subjects tested. T cell (CD3+) production of interleukin-2 (IL-2) was significantly decreased after space flight, as was IL-2 production by both CD4+ and CD8+ T cell subsets. Production of interferon-gamma (IFN-gamma) was not altered by space flight for the CD8+ cell subset, but there was a significant decrease in IFN-gamma production for the CD4+ T cell subset. Serum and urine stress hormone analysis indicated significant physiologic stresses in astronauts following space flight. Altered peripheral leukocyte subsets, altered serum and urine stress hormone levels, and altered T cell cytokine secretion profiles were all observed postflight. In addition, there appeared to be differential susceptibility to space flight regarding cytokine secretion by T cell subsets. These alterations may be the result of either microgravity exposure or the physiologic stresses of landing and readaptation to unit gravity. Future studies, including in-flight analysis or sampling, will be necessary to determine the cause of these alterations.

NASA Discipline Cell Biology↗
NASA NTRS1998

Cerebellar microfolia and other abnormalities of neuronal growth, migration, and lamination in the Pit1dw-J homozygote mutant mouse

The Snell dwarf mouse (Pit1dw-J homozygote) has a mutation in the Pit1 gene that prevents the normal formation of the anterior pituitary. In neonates and adults there is almost complete absence of growth hormone (GH), prolactin (PRL), thyroxin (T4), and thyroid-stimulating hormone (TSH). Since these hormones have been suggested to play a role in normal development of the central nervous system (CNS), we have investigated the effects of the Pit1dw-J mutation on the cerebellum and hippocampal formation. In the cerebellum, there were abnormalities of both foliation and lamination. The major foliation anomalies were 1) changes in the relative size of specific folia and also the proportional sizes of the anterior vs posterior cerebellum; and 2) the presence of between one and three microfolia per half cerebellum. The microfolia were all in the medial portion of the hemisphere in the caudal part of the cerebellum. Each microfolium was just rostral to a normal fissure and interposed between the fissure and a normal gyrus. Lamination abnormalities included an increase in the number of single ectopic granule cells in the molecular layer in both cerebellar vermis (86%) and hemisphere (40%) in comparison with the wild-type mouse. In the hippocampus of the Pit1dw-J homozygote mouse, the number of pyramidal cells was decreased, although the width of the pyramidal cell layer throughout areas CA1-CA3 appeared to be normal, but less densely populated than in the wild-type mouse. Moreover, the number of granule cells that form the granule cell layer was decreased from the wild-type mouse and some ectopic granule cells (occurring both as single cells and as small clusters) were observed in the innermost portion of the molecular layer. The abnormalities observed in the Pit1dw-J homozygote mouse seem to be caused by both direct and indirect effects of the deficiency of TSH (or T4), PRL, or GH rather than by a direct effect of the deletion of Pit1.

Non-NASA Center↗
NASA NTRS1997

Interaction of thyroid state and denervation on skeletal myosin heavy chain expression

The goal of this study was to examine the effects of altered thyroid state and denervation (Den) on skeletal myosin heavy chain (MHC) expression in the plantaris and soleus muscles. Rats were subjected to unilateral denervation (Den) and randomly assigned to one of three groups: (1) euthyroid; (2) hyperthyroid; (3) and hypothyroid. Denervation caused severe muscle atrophy and muscle-type specific MHC transformation. Denervation transformed the soleus to a faster muscle, and its effects required the presence of circulating thyroid hormone. In contrast, denervation transformed the plantaris to a slower muscle independently of thyroid state. Furthermore, thyroid hormone effects did not depend upon innervation status in the soleus, while they required the presence of the nerve in the plantaris. Collectively, these findings suggest that both thyroid hormone and intact nerve (a) differentially affect MHC transformations in fast and slow muscle; and (b) are important factors in regulating the optimal expression of both type I and IIB MHC genes. This research suggests that for patients with nerve damage and/or paralysis, both muscle mass and biochemical properties can also be affected by the thyroid state.

NASA Discipline Musculoskeletal↗
NASA NTRS1997

17beta-estradiol potently suppresses cAMP-induced insulin-like growth factor-I gene activation in primary rat osteoblast cultures

Insulin-like growth factor-I (IGF-I) is a key factor in bone remodeling. In osteoblasts, IGF-I synthesis is enhanced by parathyroid hormone and prostaglandin E2 (PGE2) through cAMP-activated protein kinase. In rats, estrogen loss after ovariectomy leads to a rise in serum IGF-I and an increase in bone remodeling, both of which are reversed by estrogen treatment. To examine estrogen-dependent regulation of IGF-I expression at the molecular level, primary fetal rat osteoblasts were co-transfected with the estrogen receptor (hER, to ensure active ER expression), and luciferase reporter plasmids controlled by promoter 1 of the rat IGF-I gene (IGF-I P1), used exclusively in these cells. As reported, 1 microM PGE2 increased IGF-I P1 activity by 5-fold. 17beta-Estradiol alone had no effect, but dose-dependently suppressed the stimulatory effect of PGE2 by up to 90% (ED50 approximately 0.1 nM). This occurred within 3 h, persisted for at least 16 h, required ER, and appeared specific, since 17alpha-estradiol was 100-300-fold less effective. By contrast, 17beta-estradiol stimulated estrogen response element (ERE)-dependent reporter expression by up to 10-fold. 17beta-Estradiol also suppressed an IGF-I P1 construct retaining only minimal promoter sequence required for cAMP-dependent gene activation, but did not affect the 60-fold increase in cAMP induced by PGE2. There is no consensus ERE in rat IGF-I P1, suggesting novel downstream interactions in the cAMP pathway that normally enhances IGF-I expression in skeletal cells. To explore this, nuclear extract from osteoblasts expressing hER were examined by electrophoretic mobility shift assay using the atypical cAMP response element in IGF-I P1. Estrogen alone did not cause DNA-protein binding, while PGE2 induced a characteristic gel shift complex. Co-treatment with both hormones caused a gel shift greatly diminished in intensity, consistent with their combined effects on IGF-I promoter activity. Nonetheless, hER did not bind IGF-I cAMP response element or any adjacent sequences. These results provide new molecular evidence that estrogen may temper the biological effects of hormones acting through cAMP to regulate skeletal IGF-I expression and activity.

Non-NASA Center↗
NASA NTRS1994

Cloning and regulation of rat tissue inhibitor of metalloproteinases-2 in osteoblastic cells

Rat tissue inhibitor of metalloproteinases-2 (TIMP-2) was cloned from a UMR 106-01 rat osteoblastic osteosarcoma cDNA library. The 969-bp full-length clone demonstrates 98 and 86% sequence identity to human TIMP-2 at the amino acid and nucleic acid levels, respectively. Parathyroid hormone (PTH), at 10(-8) M, stimulates an approximately twofold increase in both the 4.2- and 1.0-kb transcripts over basal levels in UMR cells after 24 h of exposure. The PTH stimulation of TIMP-2 transcripts was not affected by the inhibitor of protein synthesis, cycloheximide (10(-5) M), suggesting a primary effect of the hormone. This is in contradistinction to regulation of interstitial collagenase (matrix metalloproteinase-1) by PTH in these same cells. Nuclear run-on assays demonstrate that PTH causes an increase in TIMP-2 transcription that parallels the increase in message levels. Parathyroid hormone, in its stimulation of TIMP-2 mRNA, appears to act through a signal transduction pathway involving protein kinase A (PKA) since the increase in TIMP-2 mRNA is reproduced by treatment with the cAMP analogue, 8-bromo-cAMP (5 x 10(-3) M). The protein kinase C and calcium pathways do not appear to be involved due to the lack of effect of phorbol 12-myristate 13-acetate (2.6 x 10(-6) M) and the calcium ionophore, ionomycin (10(-7) M), on TIMP-2 transcript abundance. In this respect, regulation of TIMP-2 and collagenase in osteoblastic cells by PTH are similar. However, we conclude that since stimulation of TIMP-2 transcription is a primary event, the PKA pathway must be responsible for a direct increase in transcription of this gene.

Non-NASA Center↗
NASA NTRS1991

A serum factor promotes collagenase synthesis by an osteoblastic cell line

Regulation of the synthesis of collagenase was investigated in the osteoblastic cell line, UMR 106-01. The cells were stained by the avidin-biotin-complex technique for the presence of the enzyme. By this method, it was possible to identify cells producing collagenase. Synthesis, but not secretion, was found to be constitutive in these cells with the enzyme located intracellularly in cytoplasmic vesicles and the Golgi apparatus. The amount of collagenase contained within UMR cells and the number of cells synthesizing the enzyme were proportional to the concentration of fetal bovine serum in the incubating medium. When serum was withdrawn from the osteosarcoma cells, the content of collagenase decreased with time and the enzyme became undetectable by 48 h of serum depletion. The decrease in collagenase content could be completely reversed by resupplying serum to the cells. The collagenase promoting activity of serum could not be eliminated by adsorption on activated charcoal but was retained by a dialysis membrane with a 12,000 mol wt cutoff. A range of bone-seeking hormones or agents known to affect collagenase secretion was added to the medium in an attempt to mimic the effect of serum on collagenase accumulation. None of these agonists, including parathyroid hormone, could reproduce the effect of serum on these cells, although parathyroid hormone could act as a collagenase secretagogue in the presence or absence of serum. It is concluded that fetal bovine serum contains a yet unidentified factor or factors greater than 12,000 mol wt responsible for the continued synthesis of collagenase by UMR 106-01 cells.

Non-NASA Center↗
NASA NTRS2005

Multiple melanocortin receptors are expressed in bone cells

Melanocortin receptors belong to the seven transmembrane domain, G-protein coupled family of receptors. There are five members of this receptor family labeled MC1R-MC5R. These receptors are activated by fragments derived from a larger molecule, proopiomelanocortin (POMC) and include ACTH, alpha beta and gamma-MSH and beta-endorphin. Because of in vitro and in vivo data suggesting direct effects of these POMC molecules on bone and bone turnover, we examined bone and bone derived cells for the presence of the various members of the melanocortin receptor family. We report that the five known melanocortin receptors are expressed to varying degrees in osteoblast-like and osteoclastic cells. POMC fragments increased proliferation and expression of a variety of genes in osteoblastic cells. Furthermore, POMC mRNA was detected in osteoclastic cells. These data demonstrate that POMC-derived peptide hormones acting through high affinity melanocortin receptors have specific effects on bone cells. Thus, in addition to the indirect effects of POMC-derived hormones on bone turnover through their modulation of steroid hormone secretion, POMC fragments may have direct and specific effects on bone cell subpopulations.

NASA Discipline Musculoskeletal↗
NASA NTRSDate not supplied

Dry Saliva Development-Artemis

Prior to the deployment of prolonged deep space missions which may carry increased crew health risks, it is essential to determine the effect that missions beyond the Van Allen Belt will have on physiology. Historically the National Aeronautics and Space Administration (NASA), Human Research Program (HRP) has developed, conducted, and delivered research findings and countermeasures that will maintain the health and safety of crews aboard the International Space Station (ISS) in anticipation of future exploration class missions. To support these objectives, research operations on ISS typically include the collection and storage of human physiological samples and their return to Earth for analysis. Transition to Gateway and Artemis lunar exploration will limit the available up mass and biosample return capability resulting in new challenges to monitor crew health during the mission. The Artemis lunar missions provide a perfect opportunity to assess new technology that could support crew biosample return that is compatible with the severe operational constraints of Artemis mission design. Dried biosample chemistry analysis is a potential technology that can enable the collection of samples and tracking of crew health during these exploration class missions. The development and implementation of dried biosample chemistry technology for tracking immune health, viral reactivation and hormone fluctuations provide a simple alternative strategy for sample collection and sample return (light weight non-conditioned stowage option) for the continuation of human research during Artemis missions. Saliva is established as an informative biosample that has both its own unique available analytes as well as others that are also present in blood. Saliva is already routinely collected from ISS astronauts for the detection of stress hormones and latent virus DNA. The ‘Dry Saliva’ book sample collection/storage protocol, already successfully deployed to ISS, represents a perfect method for collecting biosamples from Gateway and Artemis astronauts because it requires a simple, non-invasive sample collection protocol, minimum volume, and uses non-conditioned storage. We are currently conducting an expanded stability study of the dry saliva analyte platform to include additional stress hormones, cytokines, antimicrobial proteins, and latent virus DNA as well as other markers of immunity and inflammation. Validation testing on parabolic flight will establish collection methods for saliva and blood to dry sampling substrates to finalize the collection protocols for flight. For the new expanded analyte stability study, a short-term stability study with time points out to 14 days has been completed with analysis underway to determine whether additional analytes could be recovered, as well as assessing the best storage conditions for the samples collected. In parallel, a long-term stability study is being conducted out to 1 year to improve the stability of some unstable analytes. To this end, the NASA Johnson Space Center’s Immunology/Virology lab is currently finalizing the saliva dry chemistry platform, including assay compatibility and stability studies. This technology is approved to be implemented, as part of the ‘Biomarkers’ study, during Artemis II through Artemis IV lunar missions.

Mayra Nelman-Gonzalez↗
DOE OSTI2021

Association of microbial dynamics with urinary estrogens and estrogen metabolites in patients with endometriosis

Endometriosis is an estrogen dependent gynecological disease associated with altered microbial phenotypes. The association among endogenous estrogen, estrogen metabolites, and microbial dynamics on disease pathogenesis has not been fully investigated. Here, we identified estrogen metabolites as well as microbial phenotypes in non-diseased patients (n = 9) and those with pathologically confirmed endometriosis (P-EOSIS, n = 20), on day of surgery (DOS) and ~1–3 weeks post-surgical intervention (PSI). Then, we examined the effects of surgical intervention with or without hormonal therapy (OCPs) on estrogen and microbial profiles of both study groups. For estrogen metabolism analysis, liquid chromatography/tandem mass spectrometry was used to quantify urinary estrogens. The microbiome data assessment was performed with Next generation sequencing to V4 region of 16S rRNA. Surgical intervention and hormonal therapy altered gastrointestinal (GI), urogenital (UG) microbiomes, urinary estrogen and estrogen metabolite levels in P-EOSIS. At DOS, 17β-estradiol was enhanced in P-EOSIS treated with OCPs. At PSI, 16-keto-17β-estradiol was increased in P-EOSIS not receiving OCPs while 2-hydroxyestradiol and 2-hydroxyestrone were decreased in P-EOSIS receiving OCPs. GI bacterial α-diversity was greater for controls and P-EOSIS that did not receive OCPs. P-EOSIS not utilizing OCPs exhibited a decrease in UG bacterial α-diversity and differences in dominant taxa, while P-EOSIS utilizing OCPs had an increase in UG bacterial α-diversity. P-EOSIS had a strong positive correlation between the GI/UG bacteria species and the concentrations of urinary estrogen and its metabolites. These results indicate an association between microbial dysbiosis and altered urinary estrogens in P-EOSIS, which may impact disease progression.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

PET Imaging Agents (FES, FFNP, and FDHT) for Estrogen, Androgen, and Progesterone Receptors to Improve Management of Breast and Prostate Cancers by Functional Imaging

Many breast and prostate cancers are driven by the action of steroid hormones on their cognate receptors in primary tumors and in metastases, and endocrine therapies that inhibit hormone production or block the action of these receptors provide clinical benefit to many but not all of these cancer patients. Because it is difficult to predict which individuals will be helped by endocrine therapies and which will not, positron emission tomography (PET) imaging of estrogen receptor (ER) and progesterone receptor (PgR) in breast cancer, and androgen receptor (AR) in prostate cancer can provide useful, often functional, information on the likelihood of endocrine therapy response in individual patients. This review covers our development of three PET imaging agents, 16α-[ 18 F]fluoroestradiol (FES) for ER, 21-[ 18 F]fluoro-furanyl-nor-progesterone (FFNP) for PgR, and 16β-[ 18 F]fluoro-5α-dihydrotestosterone (FDHT) for AR, and the evolution of their clinical use. For these agents, the pathway from concept through development tracks with an emerging understanding of critical performance criteria that is needed for successful PET imaging of these low-abundance receptor targets. Progress in the ongoing evaluation of what they can add to the clinical management of breast and prostate cancers reflects our increased understanding of these diseases and of optimal strategies for predicting the success of clinical endocrine therapies.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Connecting research and teaching introductory cell and molecular biology using an Arabidopsis mutant screen

A complex research project was translated into a Course-based Undergraduate Research Experience (CURE), which was implemented in sections of an introductory Cell and Molecular Biology laboratory course. The research laboratory generated an engineered plant line producing a growth-inhibiting, lipid-derived plant hormone and mutagenized this line. Students in the CURE cultured the mutagenized plant population and selected and characterized suppressor mutants. They learned to observe phenotypes related to the biosynthesis and perception of the plant hormone and explored the genetic and biochemical basis of these phenotypes. As the students studied the relevant genetic, molecular and biochemical concepts during this CURE, they were able to translate this knowledge into practice and develop scientific arguments. This CURE was a successful collaboration between the teaching lab and the research lab. It benefited both parties as the students had a real-life, deep learning experience in scientific methodology, while the research lab gathered data and materials for further studies

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

A Comprehensive Scientific Survey of Excipients Used in Currently Marketed, Therapeutic Biological Drug Products

The steady development of biotechnology-derived therapeutic biologics over the last few decades has generated drugs that are now standard medical treatments for a range of indications. While the development of protein products has surged in recent years, the formulation and delivery of these complex molecules have relied on drug-specific studies and, in some instances, data from non-proteinaceous drug products. The commonalities, trends, and gaps in excipient technologies used to support the development of therapeutic proteins largely remain unexplored due to the drug-specific nature of many formulations. Using a comprehensive and relational database approach, we aimed to provide a scientific survey of all approved or licensed biotechnology-derived drug products with the goal of providing evidence-based information on common attributes and trending features in protein product excipients. We examined 665 formulations, and 395 unique formulations based on having unique excipients within them, that supported 211 therapeutic proteins as of June 2020. We report the prevalence of each excipient class and excipient chemical used in eight different drug types including monoclonal antibodies, antibody conjugates, cytokines and growth factors, enzymes, polypeptide hormones, pulmonary surfactants, recombinant fusion proteins, and toxins. We also report the prevalence by excipient type among all therapeutic proteins, in the context of each drug’s recommended pH range, concentration ranges for excipients, and route of administration. The results of our analyses indicate certain excipients common to monoclonal antibodies, cytokines, and polypeptide hormones. We also report on excipients unique to protein drug products, such as amino acids, solubilizers, and lyoprotectants. Overall, our report summarizes the current landscape of excipients used in marketed biotechnology-derived therapeutic biologic products.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2026

Lethality is Local, but Survival is Systemic: Temporal and Multi-Organ Responses to Chlorine Gas Exposure in a Murine Model

Chlorine gas (Cl2) is a highly toxic chemical associated with both localized lung injury and systemic health effects. While pulmonary damage has been well characterized, the systemic inflammatory and metabolic responses remain poorly understood. We aimed to define the temporal and multi-organ responses to Cl2 exposure in a murine model, with a focus on identifying spatiotemporal inflammation and its impact on survival and lethality. SKH1 mice were exposed for 10 min to varying concentrations of Cl2 (94.4–810 ppm, representative of non-lethal, LD10, and LD50 doses) and monitored for respiratory function, perfusion, and acidosis using organ-specific imaging. At multiple time points (40 min, 6 h, 24 h, and 7 d), we measured phosphoproteins, cytokines, chemokines, growth factors, and metabolic hormones in the lungs, heart, cortex, and plasma. Statistical modeling and logistic regression were used to identify biomarkers associated with lethality and survival. We found that lung injury was the primary cause of potential lethality, particularly via early phosphoprotein signaling disruptions. However, survival correlated with early systemic coordination of inflammatory and metabolic signals across organs. Perfusion and acidosis imaging were strongly associated with chemokine and hormone responses. Key survival-associated plasma biomarkers included decreased insulin, increased ghrelin, and decreased eotaxin. While potential lethality from Cl2 exposure is locally driven by pulmonary injury, survival depends on systemic, multi-organ responses that occur rapidly post-exposure. Within this model, our findings identify a potential therapeutic window to enhance survival and suggest candidate biomarkers that may be explored translationally for both triage and treatment of chlorine-related incidents.

chlorine gas↗
DOE OSTI2023

Sex-specific respiratory and systemic endocrine effects of acute acrolein and trichloroethylene inhalation

Acrolein and trichloroethylene (TCE) are priority hazardous air pollutants due to environmental prevalence and adverse health effects; however, neuroendocrine stress-related systemic effects are not characterized. Comparing acrolein, an airway irritant, and TCE with low irritancy, we hypothesized that airway injury would be linked to neuroendocrine-mediated systemic alterations. Male and female Wistar-Kyoto rats were exposed nose-only to air, acrolein or TCE in incremental concentrations over 30 min, followed by 3.5-hr exposure to the highest concentration (acrolein - 0.0, 0.1, 0.316, 1, 3.16 ppm; TCE - 0.0, 3.16, 10, 31.6, 100 ppm). Real-time head-out plethysmography revealed acrolein decreased minute volume and increased inspiratory-time (males>females), while TCE reduced tidal-volume. Acrolein, but not TCE, inhalation increased nasal-lavage-fluid protein, lactate-dehydrogenase activity, and inflammatory cell influx (males>females). Neither acrolein nor TCE increased bronchoalveolar-lavage-fluid injury markers, although macrophages and neutrophils increased in acrolein-exposed males and females. Systemic neuroendocrine stress response assessment indicated acrolein, but not TCE, increased circulating adrenocorticotrophic hormone, and consequently corticosterone, and caused lymphopenia, but only in males. Acrolein also reduced circulating thyroid-stimulating hormone, prolactin, and testosterone in males. Furthermore, acute acrolein inhalation resulted in sex-specific upper respiratory irritation/inflammation and systemic neuroendocrine alterations linked to hypothalamic-pituitary-adrenal axes activation, which is critical in mediating extra-respiratory effects.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2022

Unconventional isoquinoline-based SERMs elicit fulvestrant-like transcriptional programs in ER+ breast cancer cells

Estrogen receptor alpha (ERα) is a ligand-dependent master transcriptional regulator and key driver of breast cancer pathology. Small molecule hormones and competitive antagonists favor unique ERα conformational ensembles that elicit ligand-specific transcriptional programs in breast cancer and other hormone-responsive tissues. By affecting disparate ligand binding domain structural features, unconventional ligand scaffolds can redirect ERα genomic binding patterns to engage novel therapeutic transcriptional programs. To improve our understanding of these ERα structure-transcriptional relationships, we develop a series of chemically unconventional antagonists based on the antiestrogens elacestrant and lasofoxifene. High-resolution x-ray co-crystal structures show that these molecules affect both classical and unique structural motifs within the ERα ligand binding pocket. They show moderately reduced antagonistic potencies on ERα genomic activities but are effective anti-proliferative agents in luminal breast cancer cells. Interestingly, they favor a 4-hydroxytamoxifen-like accumulation of ERα in breast cancer cells but lack uterotrophic activities in an endometrial cell line. Importantly, RNA sequencing shows that the lead molecules engage transcriptional pathways similar to the selective estrogen receptor degrader fulvestrant. This advance shows that fulvestrant-like genomic activities can be achieved without affecting ERα accumulation in breast cancer cells.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

De novo design of high-affinity binders of bioactive helical peptides

Many peptide hormones form an α-helix on binding their receptors, and sensitive methods for their detection could contribute to better clinical management of disease. De novo protein design can now generate binders with high affinity and specificity to structured proteins. However, the design of interactions between proteins and short peptides with helical propensity is an unmet challenge. Here we describe parametric generation and deep learning-based methods for designing proteins to address this challenge. We show that by extending RFdiffusion to enable binder design to flexible targets, and to refining input structure models by successive noising and denoising (partial diffusion), picomolar-affinity binders can be generated to helical peptide targets by either refining designs generated with other methods, or completely de novo starting from random noise distributions without any subsequent experimental optimization. The RFdiffusion designs enable the enrichment and subsequent detection of parathyroid hormone and glucagon by mass spectrometry, and the construction of bioluminescence-based protein biosensors. The ability to design binders to conformationally variable targets, and to optimize by partial diffusion both natural and designed proteins, should be broadly useful.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2024

GWAS supported by computer vision identifies large numbers of candidate regulators of in planta regeneration in Populus trichocarpa

Plant regeneration is an important dimension of plant propagation and a key step in the production of transgenic plants. However, regeneration capacity varies widely among genotypes and species, the molecular basis of which is largely unknown. Association mapping methods such as genome-wide association studies (GWAS) have long demonstrated abilities to help uncover the genetic basis of trait variation in plants; however, the performance of these methods depends on the accuracy and scale of phenotyping. To enable a large-scale GWAS of in planta callus and shoot regeneration in the model tree Populus, we developed a phenomics workflow involving semantic segmentation to quantify regenerating plant tissues over time. We found that the resulting statistics were of highly non-normal distributions, and thus employed transformations or permutations to avoid violating assumptions of linear models used in GWAS. We report over 200 statistically supported quantitative trait loci (QTLs), with genes encompassing or near to top QTLs including regulators of cell adhesion, stress signaling, and hormone signaling pathways, as well as other diverse functions. Our results encourage models of hormonal signaling during plant regeneration to consider keystone roles of stress-related signaling (e.g. involving jasmonates and salicylic acid), in addition to the auxin and cytokinin pathways commonly considered. The putative regulatory genes and biological processes we identified provide new insights into the biological complexity of plant regeneration, and may serve as new reagents for improving regeneration and transformation of recalcitrant genotypes and species.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Regional epithelial cell diversity in the small intestine of pigs

Abstract Understanding regional distribution and specialization of small intestinal epithelial cells is crucial for developing methods to control appetite, stress, and nutrient uptake in swine. To establish a better understanding of specific epithelial cells found across different regions of the small intestine in pigs, we utilized single-cell RNA sequencing (scRNA-seq) to recover and analyze epithelial cells from duodenum, jejunum, and ileum. Cells identified included crypt cells, enterocytes, BEST4 enterocytes, goblet cells, and enteroendocrine (EE) cells. EE cells were divided into two subsets based on the level of expression of the EE lineage commitment gene, NEUROD1. NEUROD1hi EE cells had minimal expression of hormone-encoding genes and were dissimilar to EE cells in humans and mice, indicating a subset of EE cells unique to pigs. Recently discovered BEST4 enterocytes were detected in both crypts and villi throughout the small intestine via in situ staining, unlike in humans, where BEST4 enterocytes are found only in small intestinal villi. Proximal-to-distal gradients of expression were noted for hormone-encoding genes in EE cells and nutrient transport genes in enterocytes via scRNA-seq, demonstrating regional specialization. Regional gene expression in EE cells and enterocytes was validated via quantitative PCR (qPCR) analysis of RNA isolated from epithelial cells of different small intestinal locations. Though many genes had similar patterns of regional expression when assessed by qPCR of total epithelial cells, some regional expression was only detected via scRNA-seq, highlighting advantages of scRNA-seq to deconvolute cell type-specific regional gene expression when compared to analysis of bulk samples. Overall, results provide new information on regional localization and transcriptional profiles of epithelial cells in the pig small intestine.

Agriculture↗