Biochemistry, Biophysics, and Structural Biology Commons^™

Development Of Ultrafast Protein Digestion And Standards Free Quantitation Methods For Mass Spectrometric Analysis, Praneeth Ivan Joel Fnu

Dissertations

A wide variety of biologically important molecules, such as enzymes, antibodies, hormones, transporters and receptors are proteins by composition and they play key roles in biological functions such as cellular regulation, communication, metabolism and physiological function. Protein dysfunctions and abnormalities are associated with numerous diseases, making proteins critical targets for understanding disease mechanisms and developing therapeutic interventions. Protein-based therapeutics such as monoclonal antibodies, hormones and vaccines gained popularity due to their high specificity, efficacy, and ability to treat complex diseases that are often difficult to address with small-molecule drugs.

Given the important role of proteins in a variety of biological …

Identification Of Covalent Catechin Adducts Of Enoyl-Acp Reductase (Fabi) From E. Coli Using Mass Spectrometry, Francisco G. Atwi, P. M. Joyner, Rustin Ghidari

Seaver College Research And Scholarly Achievement Symposium

Enoyl-ACP reductase (FabI), an enzyme which is inhibited by catechin, is essential for lipid biosynthesis in bacteria (E. coli). Another FabI inhibitor, triclosan, has strong antibacterial effects,1 but overuse can be detrimental to the environment. Flavonoids, a class of dietary compounds, are known to have potent inhibitory effects on FabI and other kinases.2,3,4 Adducts form as a result of the biochemical reaction between flavonoids and cysteine, a modification which can be verified by m/z shifts on the mass spectra.5 Samples of E. coli protein with overexpressed FabI are utilized: the wild type with ordinary primary structure, and mutant type lacking …

Proteomic Approaches To Investigate Pp2a-B55 Substrates And Cellular Function, Brennan C. Mcewan

Dartmouth College Ph.D Dissertations

Cell division is controlled in large part by reversible protein phosphorylation. The phosphorylation state of proteins during mitosis and other phases of the cell cycle represents a careful balance of activity between kinases and opposing phosphatases. The phosphoprotein phosphatase (PPP) family is responsible for the majority of serine and threonine dephosphorylation. Members of the PPP family are composed of a catalytic subunit paired with a regulatory subunit that targets them towards specific substrates.

The most abundant PPP, PPP2A, paired with its regulatory B55 subunit, is thought to be the phosphatase responsible for the dephosphorylation of substrates during mitotic exit. Despite …

Identification Of Serum Exosome Proteins In Systemic Sclerosis With Interstitial Lung Disease By Aptamer Proteomics, Sonsoles Piera-Velazquez, Simon T. Dillon, Xuesong Gu, Towia A. Libermann, Sergio A. Jimenez

Jefferson Institute of Molecular Medicine Papers and Presentations

OBJECTIVE: A major unmet need for Systemic Sclerosis (SSc) clinical management is the absence of well validated biomarkers for early diagnosis of SSc-associated interstitial lung disease (SSc-ILD). The objective of this study was to identify proteins contained within serum exosomes that may serve as potential biomarkers to differentiate patients with Diffuse SSc without SSc-ILD from patients with Diffuse SSc with SSc-ILD employing aptamer-based proteomics.

METHODS: Serum exosomes were isolated from two cohorts of patients. The first cohort included 15 patients with Diffuse SSc without SSc-ILD and 14 patients with Diffuse SSc with SSc-ILD and the second cohort included 12 patients …

Activity-Based Protein Profiling On Nucleophilic Amino Acid Residues With Pyrocarbonates, James Van Horn

Chemistry & Biochemistry Undergraduate Honors Theses

The complexity of the proteome requires strategies that efficiently characterize protein functions. Activity-Based Protein Profiling (ABPP) is a method that identifies enzyme activity by targeting key catalytic residues. This study focused on histidine, a residue involved in enzymatic catalysis, metal coordination, and protein-protein interactions. Despite its importance, histidine-specific chemical probes are limited due to its variable reactivity. This work developed and characterized a histidine-specific probe using a pyrocarbonate-based mechanism. Singleresidue assays confirmed selective reactivity of the probe with histidine over other nucleophilic amino acids. Further testing on enzymatic proteins and lysed cell proteomes showed that the probe modified histidine residues …

Proteomics Of Extracellular Vesicles: Recent Updates, Challenges And Limitations, Mohini Singh, Prashant Kumar Tiwari, Vivek Kumar Kashyap, Sanjay Kumar

School of Medicine Publications

Extracellular vesicles (EVs) are lipid-bound vesicles secreted by cells, including exosomes, microvesicles, and apoptotic bodies. Proteomic analyses of EVs, particularly in relation to cancer, reveal specific biomarkers crucial for diagnosis and therapy. However, isolation techniques such as ultracentrifugation, size-exclusion chromatography, and ultrafiltration face challenges regarding purity, contamination, and yield. Contamination from other proteins complicates downstream processing, leading to difficulties in identifying biomarkers and interpreting results. Future research will focus on refining EV characterization for diagnostic and therapeutic applications, improving proteomics tools for greater accuracy, and exploring the use of EVs in drug delivery and regenerative medicine. In this review, we …

P23h Rhodopsin Accumulation Disrupts Synaptic Protein Levels In Rod Photoreceptors, Samantha Thompson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Rod photoreceptors are specialized neurons located in the retina, the neural tissue that lines the back of the eye. Rod photoreceptors are necessary for dim light and peripheral vision through the photoactivation rhodopsin (Rho). Rho is synthesized in the inner segment of rods before being unidirectionally trafficked to the outer segment. In diseases such as retinitis pigmentosa (RP), Rho trafficking can be disrupted, leading to progressive rod cell death. In many cases of RP, Rho is mislocalized to the rod photoreceptor synapse (“spherule”). The impact of Rho mislocalization on spherule structure and protein organization is poorly understood. We hypothesize that …

Integrated Transcriptomics And Proteomics Study Of Starvation Selected Drosophila Melanogaster, Aavash Adhikari

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drosophila melanogaster, selected for starvation resistance exhibits phenotypic traits such as increased body size, slower development, reduced fecundity and obesity like characteristics including higher lipid reserves and cardiac dysfunction. While prior studies have explored the metabolic and biochemical changes in these flies, the underlying genetic and molecular mechanisms remain unclear. This study aims to investigate the gene expression and protein abundance in starvation-selected Drosophila through RNAseq, proteomics, and integrating both datasets using the MixOmics package in R. I found differential gene expression in the fat body at the third instar larval stage, particularly in pathways related to lipid metabolism, calcium …

Quantitative Proteomic Strategies To Determine Substrate Specificities Of Phosphoprotein Phosphatases, Hieu Trung Nguyen

Dartmouth College Ph.D Dissertations

Reversible phosphorylation is a crucial regulatory mechanism of cellular signaling pathways. Being the most prevalent post-translational modification (PTM) in the cells, with over 75% of all proteins detected to be phosphorylated, phosphorylation regulates a significant number of important cellular processes that have implications in various diseases. Phosphorylation is carried out by protein kinases, which have been extensively studied. However, the opposite reaction, carried out by protein phosphatases, has lagged significantly, exposing a gap of knowledge that is required to be investigated to delineate the kinase-substrate-phosphatase relationship. Phosphoprotein phosphatase family (PPPs), containing seven members of phospho-Serine (pS) and phospho-Threonine (pT) phosphatases, …

Maldi-Msi Identification Of Tissue-Level N-Glycomic And Proteomic Molecular Biomarkers Of Aggressive Prostate Cancer, Jordan Paige Hartig

MUSC Theses and Dissertations

Prostate Cancer (PCa) poses a significant clinical challenge, characterized by debates on screening efficacy and continuous issues with distinguishing aggressive from non-aggressive tumors. Despite treatment advancements, poor patient outcome at late stages and clinical overtreatment of indolent disease emphasizes the urgent need for markers of PCa aggression. Aberrant glycosylation and extracellular matrix (ECM) remodeling are two complex molecular processes necessary for PCa progression, highlighting a novel area for biomarker discovery. Leveraging formalin-fixed paraffin-embedded tissues, tissue microarrays (TMAs), and matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), distinct N-glycan and ECM profiles are identified. Elevated bisecting, multi-antennary, and fucosylated N-glycans indicate early …

Differentially Disrupted Spinal Cord And Muscle Energy Metabolism In Spinal And Bulbar Muscular Atrophy, Danielle Debartolo, Frederick Arnold, Y Liu, Elana Molotsky, Hsin-Yao Tang, Diane Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Prior studies showed that polyglutamine-expanded androgen receptor (AR) is aberrantly acetylated and that deacetylation of the mutant AR by overexpression of nicotinamide adenine dinucleotide-dependent (NAD+-dependent) sirtuin 1 is protective in cell models of spinal and bulbar muscular atrophy (SBMA). Based on these observations and reduced NAD+ in muscles of SBMA mouse models, we tested the therapeutic potential of NAD+ restoration in vivo by treating postsymptomatic transgenic SBMA mice with the NAD+ precursor nicotinamide riboside (NR). NR supplementation failed to alter disease progression and had no effect on increasing NAD+ or ATP content in muscle, despite producing a modest increase of …

Personalized Molecular Therapies For Advanced Non-Small Cell Lung Cancer: Overcoming Heterogeneity To Optimize Treatment Response And Clinical Outcomes, Zuan-Fu Lim

Graduate Theses, Dissertations, and Problem Reports (ETD)

Lung cancer remains one of the deadliest cancers. Novel, paradigm shifting treatments including immunotherapy and targeted therapies have recently been developed to cull the deadly effects of lung cancer, but many challenges remain. There remains a significant unmet need to accurately predict and optimally select for patients who will respond to immune checkpoint inhibitors (ICI) treatment. In Chapter 2 of this dissertation, we investigated a novel live single cell cytokine profiling lab-on-chip platform, IsoLight, using peripheral CD4+ and CD8+ T-cells for ICI biomarker development. A total of 55,175 single T-lymphocytes were analyzed in this proof-of-concept study. We found that an …

Quantum Dots' Toxicity: A Multi-Level Investigation On The Impact Of Quantum Dots On The Actin Cytoskeleton, Nhi Le

Graduate Theses/Dissertations

Quantum dots (QDs) are fluorescence nanomaterials with unique optical and physical properties. As such, they are highly sought after for their potential use in several biomedical and industrial applications. Despite their vast potential, recent studies have suggested that quantum dots are toxic to cells. Yet, the mechanism of quantum dots’ toxicity remains unclear. As such, my thesis aims to comprehensively examine the mechanism of quantum dots’ toxicity, emphasizing how quantum dots disrupt the actin cytoskeleton. In this study, I used RNA sequencing and mass spectrometry to investigate the influence of CdSe/ZnS QDs on the transcriptomic proteomic level of Saccharomyces cerevisiae …

Characterizing 4,4’-Methylene Diphenyl Diisocyanate Exposure In Primary Human Epidermal Keratinocytes: A Multi-Omics Approach, Brandon F. Law

Graduate Theses, Dissertations, and Problem Reports (ETD)

Exploring the routes of exposure and biological fate of 4,4’-methylene diphenyl diisocyanate (MDI) has been a challenge for many years. Occupational exposure to MDI can result in the development of occupational asthma (MDI-OA) which results in loss of productivity, large economic costs, and costs to the individual worker. Initially, it was thought that respiratory exposure to MDI was the most likely route leading to MDI-OA. Industries utilizing MDI have been successful at controlling airborne concentrations according to industrial hygiene assessment and newly diagnosed cases of MDI-OA decreased and plateaued. New research suggests that dermal exposures to MDI may explain this …

Effects Of Doxorubicin On Extracellular Matrix Regulation In Primary Cardiac Fibroblasts From Mice, Cameron Skaggs, Steve Nick, Conner Patricelli, Laura Bond, Kali Woods, Luke Woodbury, Julia Thom Oxford, Xinzhu Pu

Biomedical Research Institute Publications and Presentations

Objective Doxorubicin (DOX) is a highly effective chemotherapeutic used to treat many adult and pediatric cancers. However, its use is limited due to a dose-dependent cardiotoxicity, which can lead to lethal cardiomyopathy. In contrast to the extensive research efforts on toxic effects of DOX in cardiomyocytes, its effects and mechanisms on cardiac extracellular matrix (ECM) homeostasis and remodeling are poorly understood. In this study, we examined the potential effects of DOX on cardiac ECM to further our mechanistic understanding of DOX-induced cardiotoxicity.

Results DOX-induced significant down-regulation of several ECM related genes in primary cardiac fibroblasts, including Adamts1, Adamts5, Col4a1, Col4a2, …

Elucidation Of Molecular Mechanisms Underlying Novel Multi-Targeted Therapy Strategies For, Qianqian Hu

USF Tampa Graduate Theses and Dissertations

EML4-ALK fusion non-small cell lung cancer (NSCLC) represents a distinct subset of lung cancers that possesses unique molecular and clinical features, paving the way for targeted therapeutic interventions. Despite the promise of ALK-directed therapies, challenges such as metastasis at the time of diagnosis and treatment resistance persist, necessitating deeper research into the underlying mechanisms and potential solutions. In the context of these challenges, our study embarked on two specific objectives. The first goal, elucidated in Chapter 2, revolved around brain metastasis, an event critically facilitated by cell migration. Here, we assessed the anti-migratory activities of several clinical ALK inhibitors in …

Pyrroline-5-Carboxylate Reductase-2 Promotes Colorectal Carcinogenesis By Modulating Microtubule-Associated Serine/Threonine Kinase-Like/Wnt/Β-Catenin Signaling, Raju Lama Tamang, Balawant Kumar, Sagar M. Patel, Ishwor Thapa, Alshomrani Ahmad, Vikas Kumar, Rizwan Ahmad, Donald F. Becker, Dundy Kiran Bastola, Punita Dhawan, Amar B. Singh

Department of Biochemistry: Faculty Publications

Background: Despite significant progress in clinical management, colorectal cancer (CRC) remains the third most common cause of cancer-related deaths. A positive association between PYCR2 (pyrroline-5-carboxylate reductase-2), a terminal enzyme of proline metabolism, and CRC aggressiveness was recently reported. However, how PYCR2 promotes colon carcinogenesis remains ill understood. Methods: A comprehensive analysis was performed using publicly available cancer databases and CRC patient cohorts. Proteomics and biochemical evaluations were performed along with genetic manipulations and in vivo tumor growth assays to gain a mechanistic understanding. Results: PYCR2 expression was significantly upregulated in CRC and associated with poor patient survival, specifically among PYCR …

Proteomic Approaches To Identify Unique And Shared Substrates Among Kinase Family Members, Charles Lincoln Howarth

Dartmouth College Ph.D Dissertations

Protein phosphorylation is a reversible post-translational modification that is a critical component of almost all signaling pathways. Kinases regulate substrate proteins through phosphorylation, and nearly all proteins are phosphorylated to some extent. Crucially, breakdown in phosphorylation signaling is an underlying factor in many diseases, including cancer. Understanding how phosphorylation signaling mediates cellular pathways is crucial for understanding cell biology and human disease.

Targeted protein degradation (TPD) is a strategy to rapidly deplete a protein of interest (POI) and is applicable to any gene that is amenable to CRISPR-Cas9 editing. One TPD approach is the auxin-inducible degron (AID) system, which relies …

Molecular Dissection And Testing Of Prss37 Function Through Lc-Ms/Ms And The Generation Of A Prss37 Humanized Mouse Model, Courtney Sutton, Kaori Nozawa, Katarzyna Kent, Alexander Saltzman, Mei Leng, Sureshbabu Nagarajan, Anna Malovannaya, Masahito Ikawa, Thomas X Garcia, Martin M Matzuk

Faculty, Staff and Students Publications

The quest for a non-hormonal male contraceptive pill for men still exists. Serine protease 37 (PRSS37) is a sperm-specific protein that when ablated in mice renders them sterile. In this study we sought to examine the molecular sequelae of PRSS37 loss to better understand its molecular function, and to determine whether human PRSS37 could rescue the sterility phenotype of knockout (KO) mice, allowing for a more appropriate model for drug molecule testing. To this end, we used CRISPR-EZ to create mice lacking the entire coding region of Prss37, used pronuclear injection to create transgenic mice expressing human PRSS37, intercrossed these …

Testis-Specific Serine Kinase 3 Is Required For Sperm Morphogenesis And Male Fertility, Kaori Nozawa, Thomas X Garcia, Katarzyna Kent, Mei Leng, Antrix Jain, Anna Malovannaya, Fei Yuan, Zhifeng Yu, Masahito Ikawa, Martin M Matzuk

Faculty, Staff and Students Publications

BACKGROUND: The importance of phosphorylation in sperm during spermatogenesis has not been pursued extensively. Testis-specific serine kinase 3 (Tssk3) is a conserved gene, but TSSK3 kinase functions and phosphorylation substrates of TSSK3 are not known.

OBJECTIVE: The goals of our studies were to understand the mechanism of action of TSSK3.

MATERIALS AND METHODS: We analyzed the localization of TSSK3 in sperm, used CRISPR/Cas9 to generate Tssk3 knockout (KO) mice in which nearly all of the Tssk3 open reading frame was deleted (ensuring it is a null mutation), analyzed the fertility of Tssk3 KO mice by breeding mice for 4 months, …

Physiological And Proteomic Analysis Of Soybean In Response To Drought And Heat Stress, Amandeep Kaur

Theses and Dissertations

Drought and temperature stress are the two most important factors limiting crop productivity. A physiological and proteomic analysis of soybean was performed to investigate the negative impact of these variables. The previous studies reported the beneficial effect of silicon under stress conditions. Silicon supplementation may promote plant growth under drought stress, although the mechanism to alleviate drought stress is uncertain. The proteomic analysis of chloroplast proteins was carried out to study the response of silicon supplementation under drought stress.

Similarly, temperature stress, mainly heat stress, has an adverse effect on soybean plants. The comparative analysis of two soybean cultivars, DS25-1 …

Profiling Disease-Selective Drug Targets: From Proteomics To Ligandomics, Prabuddha Waduge, Hong Tian, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Despite advancements in omics technologies, including proteomics and transcriptomics, identification of therapeutic targets remains challenging. Ligandomics recently emerged as a unique technology of functional proteomics for global profiling of cell-binding protein ligands. When applied to diseased versus healthy vasculatures, comparative ligandomics systematically maps novel disease-restricted ligands that allow selective targeting of pathological but not physiological pathways, providing high efficacy with intrinsic safety. In this review, we discuss the potential of cellular ligands as therapeutic targets and summarize the development of ligandomics. We further compare the advantages and limitations of different omics technologies for drug target discovery and discuss target selection …

Transcriptome, Proteome, And Protein Synthesis Within The Intracellular Cytomatrix, Tattym E Shaiken, Sandra L Grimm, Mohamad Siam, Amanda Williams, Abdol-Hossein Rezaeian, Daniel Kraushaar, Emily Ricco, Matthew J Robertson, Cristian Coarfa, Antrix Jain, Anna Malovannaya, Fabio Stossi, Antone R Opekun, Alyssa P Price, Julien Dubrulle

Faculty, Staff and Students Publications

Despite the knowledge that protein translation and various metabolic reactions that create and sustain cellular life occur in the cytoplasm, the structural organization within the cytoplasm remains unclear. Recent models indicate that cytoplasm contains viscous fluid and elastic solid phases. We separated these viscous fluid and solid elastic compartments, which we call the cytosol and cytomatrix, respectively. The distinctive composition of the cytomatrix included structural proteins, ribosomes, and metabolome enzymes. High-throughput analysis revealed unique biosynthetic pathways within the cytomatrix. Enrichment of biosynthetic pathways in the cytomatrix indicated the presence of immobilized biocatalysis. Enzymatic immobilization and segregation can surmount spatial impediments, …

Eluication Of Lipid Metabolic Pathways In Differentiating Giardia Lamblia Using High Resolution Mass Spectrometry, Cameron Ellis

Open Access Theses & Dissertations

Giardia lamblia is an intestinal protozoan found worldwide, including the U.S. This parasite exists in two morphologic stages - a replicative trophozoite and a relatively dormant yet viable cyst. While exposures of cysts to gastric acid during passage through the human stomach induces excystation, factors in the small intestine, where trophozoites colonize trigger encystation or cyst formation. Transformation into cyst stage is essential for Giardia to survive in the environment for months before infecting new hosts. Because of its small genome size (11.7 Mb), metabolic pathways in Giardia are highly reduced. As far as lipid metabolism is concerned, only limited …

Identification Of Genomic, Proteomic, And Metabolomic Signatures Associated With Pulmonary Hypertension Syndrome In Broilers, Duaa Almansaf

Graduate Theses and Dissertations

The present dissertation contains a collection of studies that examine the genomic, proteomic, and metabolomic association to pulmonary hypertension or ascites phenotype in fast-growing broilers. Pulmonary hypertension is a multifactorial metabolic disease influenced by physiological, environmental, and nutritional factors. It is characterized by a number of structural changes including, thrombosis and adverse pulmonary vascular remodeling. Thus, the atrial pressure is increased, and the right ventricle becomes hypertrophied, resulting in heart failure and the death of the bird. Pulmonary hypertension or ascites is a global problem that has negatively impacted the economy. The increased mortality rate of broilers (25%) is estimated …

Deciphering Phosphoprotein Phosphatase Signaling Networks Using Proteomics Approaches, Brooke Brauer

Dartmouth College Ph.D Dissertations

Protein phosphorylation is a highly regulated mechanism of cell signaling control and its deregulation is implicated in disease. The kinases that catalyze the addition of phosphate groups onto their substrate proteins have been well studied, their signaling pathways mapped, and their effects on cell and organismal health observed. Knowledge of the phosphatases that reverse the reaction only recently began to come into focus. Phosphoprotein phosphatases (PPPs), long thought to be housekeeping enzymes, are now known to be exquisitely specific towards their substrates, but the exact nature of phosphatase regulation—both upstream and downstream of the phosphatase—is unclear.

PPPs recognize substrates through …

Signature Peptide Identification For Body Fluids In Sexual Assault Cases By Liquid Chromatography Tandem Mass Spectrometry (Lc-Ms/Ms), Kelci Somers

Student Theses

Body fluids contain proteins that perform functions specific to different types of body fluids. Therefore, the detection of signature peptides for these proteins can potentially identify a body fluid in a forensic investigation. This project aimed to validate a method to detect signature peptides in body fluids commonly found in sexual assault cases by LC-MS/MS. Signature peptides for semen and saliva fluids were combined with two signature peptides for vaginal fluids. Samples created using two donors each for saliva, semen, and vaginal fluids were extracted using a trypsin digest, with separation of the protein and DNA fractions. The LC-MS/MS was …

Lipid Rafts, Exosomal Vesicles And Anti-Giardial Therapies, Brian Ivan Grajeda

Open Access Theses & Dissertations

Giardia lamblia, a protozoan parasite, is a major cause of waterborne infection, worldwide. While the trophozoite form of this parasite induces pathological symptoms in the gut, the cyst forms transmit the infection via contaminated water. Since Giardia is a non-invasive parasite, the actual mechanism by which it causes infection remains elusive. We have previously reported that Giardia assembles cholesterol and GM1 glycolipid-enriched lipid rafts (LRs) that participate in encystation and cyst production. To further delineate the role of LRs in pathogenesis, we isolated LRs from Giardia and subjected them to proteomic analysis. Various cellular proteins including the virulent proteins—e.g., giardins, …

Extending Plasma Proteome Coverage To Enable Biomarker Discovery, Jordan Bruce Burton

Wayne State University Dissertations

Two features make plasma a valued source of health information: First, plasma contains secreted proteins from all tissues in the body and can, therefore, provide information about the health status of all tissues. Second, plasma is available in large quantity using a minimally invasive procedure that is well tolerated. The status of plasma as a valued source of health information is matched by the difficulty in extracting proteome information from the samples. Using state of the art instrumentation a standard analysis of plasma yields quantitative information on approximately 300 proteins. Extreme fractionation strategies coupled with increased mass spectrometry time extends …

Steroid Receptor-Coregulator Transcriptional Complexes: New Insights From Cryoem, Ping Yi, Xinzhe Yu, Zhao Wang, Bert W O'Malley

Faculty, Staff and Students Publications

Steroid receptors activate gene transcription through recruitment of a number of coregulators to facilitate histone modification, chromatin remodeling, and general transcription machinery stabilization. Understanding the structures of full-length steroid receptor and coregulatory complexes has been difficult due to their large molecular sizes and dynamic structural conformations. Recent developments in cryo-electron microscopy (cryoEM) technology and proteomics have advanced the structural studies of steroid receptor complexes. Here, we will review the insights we learned from cryoEM studies of the estrogen and androgen receptor transcriptional complexes. Despite similar domain organizations, the two receptors have different coregulator interaction modes. The cryoEM structures now have …