About

David Greenstein, PhD, is a professor affiliated with the Genetics, Cell Biology & Development department at the University of Minnesota Medical School. The provided page text does not include specific details about his research focus, background, or key contributions.

Research topics

• Biology
• Genetics
• Cell biology
• Internal medicine
• Medicine
• Immunology
• Biochemistry
• Dermatology
• Neuroscience

Selected publications

• Anesthetic Management Alternative to Awake Tracheostomy for Pediatric Patient Who is Unable to Intubate via Supraglottic Approach due to a Large Oropharyngeal Mass

  Journal of Anesthesia & Intensive Care Medicine · 2025-07-01

  articleOpen accessSenior author
  PublisherDOI

• A sperm–oocyte protein partnership required for egg activation in <i>Caenorhabditis</i> elegans

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-01-23

  preprintOpen accessSenior authorCorresponding

  ABSTRACT Fertilization triggers the completion of female meiosis and launches the oocyte-to-embryo transition. C. elegans spe-11 is one of the few known paternal-effect embryonic lethal genes. We report that the sperm protein, SPE-11, forms a complex with an oocyte protein, OOPS-1 ( Oo cyte P artner of S PE-11), and that the protein complex is required for the completion of meiosis, the block to polyspermy, and eggshell formation. Consistent with the molecular interaction of their encoded proteins, oops-1 and spe-11 exhibit identical null phenotypes, displaying defects in meiotic progression and cytokinesis. We show that the complex binds F-actin in the absence of other proteins and inhibits the nucleation of actin filaments in vitro . Thus, the OOPS-1–SPE-11 complex may function to promote F-actin-mediated meiotic cytokinesis. Both OOPS-1 and SPE-11 are intrinsically disordered proteins that are highly phosphorylated. Biochemical and genetic experiments define interactions with the protein phosphatase 1 homologs GSP-3/4, which appear to promote OOPS-1–SPE-11 function. Genetic results support a model in which the OOPS-1–SPE-11 complex interacts with the cortical EGG complex to promote meiotic cytokinesis and to activate synthesis of the eggshell.

  PublisherDOI

• DNA-Protein Interactions in f1 DNA Replication

  Digital Commons - RU (Rockefeller University) · 2025-09-08

  articleOpen access1st authorCorresponding

  This thesis analyzes the interaction of two DNA-binding proteins with the plus strand replication origin of bacteriophage f1. The origin has a bipartite structure consisting of a required core origin region and an adjacent A+T- rich enhancer sequence that potentiates replication approximately 100-fold. The core origin binds the initiator protein, and the enhancer contains three binding sites for the E. coli integration host factor (IHF). Both activator proteins bend the DNA sequence to which they bind, implying that together they wrap the origin DNA into a higher order structure that is active in initiation. The replication initiator protein of bacteriophage f1 (gene II protein) is a multifunctional protein that participates in DNA replication at a number of levels. The gene II protein binds to the core origin in a novel two-step fashion. The first binding step involves interaction of two gene II protein molecules with an inverted repeat (β- γ) at the center of the core origin to form a binding intermediate, complex I. The second binding step involves addition of two protein molecules to complex I, resulting in formation of the functional complex, complex II. Of these two protein molecules, one binds to and contacts repeat δ, the other gene II protein molecule protects the nicking site in a sequence-independent fashion. The sequence protected in complex II corresponds to the core origin sequence as determined previously by in vivo analyses. The enhancer independent mutation mp1 in gene II protein (met⁴⁰→ile) increases the cooperativity with which the protein binds to the core origin to form complex II. A model is presented for the binding reaction involving both protein-DNA and protein-protein interactions. A major finding of this thesis is that IHF activates f1 DNA replication by binding to three sites within the replication enhancer. The growth defect of f1 in IHF mutants was shown to be at the level of DNA replication. This growth defect of f1 in IHF mutants is suppressed by an initiator mutation (mp1) that also suppresses the lack of the replication enhancer, indicating that the enhancer is the genetic site of action of IHF.

  PublisherOA PDFDOI

• The SPN-4 Rbfox RNA-binding protein selects maternal mRNAs for CCR4-NOT-dependent clearance in early <i>Caenorhabditis elegans</i> embryos

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-15

  preprintOpen access

  ABSTRACT The elimination of maternal mRNAs is an essential feature of the maternal-to-zygotic transition. We report an essential pathway that clears many maternal transcripts from early C. elegans embryos using the Rbfox-related SPN-4 RNA-binding protein as a specificity factor and the CCR4-NOT deadenylase complex as an effector. We biochemically identified SPN-4-associated mRNAs from late-stage oocytes and found that the set of SPN-4-associated transcripts is enriched for maternal mRNAs that undergo early decay. Single-molecule fluorescence in situ hybridization experiments established that many SPN-4-associated mRNAs fail to be eliminated in the absence of SPN-4. In the 3’UTRs of two target mRNAs, we identified Rbfox motifs that are required for SPN-4-dependent clearance in vivo and bind SPN-4 in vitro . In a genetic screen to identify factors that work with SPN-4, we isolated mutant alleles of CCR4-NOT components. Auxin-induced degradation of the LET-711/NOT1 scaffold and the CCF-1 deadenylase disrupted clearance of two SPN-4-associated transcripts. Our results support a model in which SPN-4 initiates expression in late-stage oocytes, associates with maternal mRNA targets through RNA sequences in their 3’UTRs and promotes CCR4-NOT-mediated decay during early embryogenesis.

  PublisherOA PDFDOI

• A sperm–oocyte protein partnership required for egg activation in <i>Caenorhabditis elegans</i>

  Development · 2025-05-30 · 4 citations

  articleOpen accessSenior author

  Fertilization triggers the completion of female meiosis and launches the oocyte-to-embryo transition. Caenorhabditis elegans spe-11 is one of the few known paternal-effect embryonic lethal genes. We report that the sperm protein SPE-11 forms a complex with an oocyte protein, OOPS-1 (Oocyte Partner of SPE-11) at fertilization, and that the protein complex is required for the completion of meiosis, the block to polyspermy, and eggshell formation. Consistent with the molecular interaction of their encoded proteins, oops-1 and spe-11 exhibit indistinguishable null phenotypes in which fertilized oocytes arrest in meiosis I or meiosis II or fail to complete the actin-based process of meiotic cytokinesis. Biochemical analysis shows that the complex binds F-actin in the absence of other proteins and inhibits the nucleation of actin filaments at substoichiometric concentrations. Both OOPS-1 and SPE-11 are intrinsically disordered proteins that are highly phosphorylated, and biochemical and genetic experiments define interactions with the sperm-specific protein phosphatase 1 homologs GSP-3/4. Genetic results suggest that the cortical EGG complex recruits the OOPS-1-SPE-11 complex at fertilization, which promotes meiotic cytokinesis and in turn activates synthesis of the eggshell.

  PublisherDOI

• Awake Tracheostomy in a Pediatric Patient

  Ear Nose & Throat Journal · 2024-09-01

  articleOpen access

  Awake tracheostomy is rare in the pediatric population. We describe the case of a 10-year-old male who underwent awake tracheostomy due to airway obstruction from an oropharyngeal rhabdomyosarcoma. Given the varying medical understanding and communication skills in children, advanced planning and interdisciplinary collaboration are essential to keep the patient calm and safe during awake tracheostomy.

  PublisherDOI

• Efficacy and Safety of Lebrikizumab in Combination With Topical Corticosteroids in Adolescents and Adults With Moderate-to-Severe Atopic Dermatitis

  JAMA Dermatology · 2023 · 134 citations

  • Medicine
  • Dermatology
  • Immunology

  Importance: Lebrikizumab (LEB), a high-affinity monoclonal antibody targeting interleukin (IL)-13, demonstrated efficacy and safety in patients with moderate-to-severe atopic dermatitis (AD) during 16 weeks of monotherapy in a phase 2b trial, and two 52-week phase 3 trials. Objective: To evaluate efficacy and safety of LEB combined with low- to mid-potency topical corticosteroids (TCS) in patients with moderate-to-severe AD. Design, Setting, and Participants: The ADhere trial was a 16-week randomized, double-blinded, placebo (PBO)-controlled, multicenter, phase 3 clinical trial conducted from February 3, 2020, to September 16, 2021. The study was conducted at 54 outpatient sites across Germany, Poland, Canada, and the US and included adolescent (aged ≥12 to <18 years weighing ≥40 kg) and adult patients with moderate-to-severe AD. The treatment allocation ratio was 2:1 (LEB:PBO). Interventions: Overall, 211 patients were randomized to subcutaneous LEB (loading dose of 500 mg at baseline and week 2, followed by 250 mg every 2 weeks [Q2W] thereafter) or PBO Q2W in combination with TCS for 16 weeks. Main Outcomes and Measures: Efficacy analyses at week 16 included proportions of patients achieving Investigator's Global Assessment score of 0 or 1 (IGA [0,1]) with 2 or more points improvement from baseline, and 75% improvement in the Eczema Area and Severity Index (EASI-75). Key secondary end points included evaluation of itch, itch interference on sleep, and quality of life. Safety assessments included monitoring adverse events (AEs). Results: The mean (SD) age of patients was 37.2 (19.3) years, 103 (48.8%) patients were women, 31 (14.7%) patients were Asian, and 28 (13.3%) patients were Black/African American. At week 16, IGA (0,1) was achieved by 145 (41.2%) patients in the LEB+TCS group vs 66 (22.1%) receiving PBO+TCS (P = .01); corresponding proportions of patients achieving EASI-75 were 69.5% vs 42.2% (P < .001). The LEB+TCS group showed statistically significant improvements in all key secondary end points. Most treatment-emergent adverse events (TEAEs) were nonserious, mild or moderate in severity, and did not lead to study discontinuation. The TEAEs frequently reported in the LEB+TCS group included conjunctivitis (7 [4.8%]), headache (7 [4.8%]), hypertension (4 [2.8%]), injection site reactions (4 [2.8%]), and herpes infection (5 [3.4%]) vs 1.5% or less patient-reported frequencies in the PBO+TCS group. Similar frequencies of patient-reported serious AEs following LEB+TCS (n = 2, 1.4%) and PBO+TCS (n = 1, 1.5%). Conclusions and Relevance: In this randomized phase 3 clinical trial, LEB+TCS was associated with improved outcomes in adolescents and adults with moderate-to-severe AD compared with TCS alone, and safety was consistent with previously reported AD trials. Trial Registration: ClinicalTrials.gov Identifier: NCT04250337.

  PublisherOA PDFDOI

• Reevaluation of the role of LIP-1 as an ERK/MPK-1 dual specificity phosphatase in the <i>C. elegans</i> germline

  Proceedings of the National Academy of Sciences · 2022-01-12 · 4 citations

  articleOpen access

  Significance The RAS–ERK pathway is critical for metazoan development. In development, ERK activity is regulated by a balance of phosphorylation of ERK by MEK (MAPK kinase) and dephosphorylation by DUSPs (dual specificity phosphatases). LIP-1, a DUSP6/7 family member, was previously suggested to regulate MPK-1/ERK activity by dephosphorylating MPK-1 in the Caenorhabditis elegans germline, based on LIP-1's mutant phenotype in the germline and its DUSP role in vulval development. However, our investigations demonstrate that LIP-1 does not function as an MPK-1 DUSP in the germline and likely regulates germline functions through distinct targets. Our results present a cautionary note about misinterpreting similar mutant phenotypes caused by mutations in different genes and assuming that genes function similarly in different tissues.

  PublisherDOI

• Author response: Innexin function dictates the spatial relationship between distal somatic cells in the Caenorhabditis elegans gonad without impacting the germline stem cell pool

  2022-03-28 · 1 citations

  peer-reviewOpen accessSenior author
  PublisherDOI

• Ubiquitin ligases and a processive proteasome facilitate protein clearance during the oocyte-to-embryo transition in <i>Caenorhabditis elegans</i>

  Genetics · 2022-04-04 · 18 citations

  articleOpen accessSenior authorCorresponding

  The ubiquitin-mediated degradation of oocyte translational regulatory proteins is a conserved feature of the oocyte-to-embryo transition. In the nematode Caenorhabditis elegans, multiple translational regulatory proteins, including the TRIM-NHL RNA-binding protein LIN-41/Trim71 and the Pumilio-family RNA-binding proteins PUF-3 and PUF-11, are degraded during the oocyte-to-embryo transition. Degradation of each protein requires activation of the M-phase cyclin-dependent kinase CDK-1, is largely complete by the end of the first meiotic division and does not require the anaphase-promoting complex. However, only LIN-41 degradation requires the F-box protein SEL-10/FBW7/Cdc4p, the substrate recognition subunit of an SCF-type E3 ubiquitin ligase. This finding suggests that PUF-3 and PUF-11, which localize to LIN-41-containing ribonucleoprotein particles, are independently degraded through the action of other factors and that the oocyte ribonucleoprotein particles are disassembled in a concerted fashion during the oocyte-to-embryo transition. We develop and test the hypothesis that PUF-3 and PUF-11 are targeted for degradation by the proteasome-associated HECT-type ubiquitin ligase ETC-1/UBE3C/Hul5, which is broadly expressed in C. elegans. We find that several GFP-tagged fusion proteins that are degraded during the oocyte-to-embryo transition, including fusions with PUF-3, PUF-11, LIN-41, IFY-1/Securin, and CYB-1/Cyclin B, are incompletely degraded when ETC-1 function is compromised. However, it is the fused GFP moiety that appears to be the critical determinant of this proteolysis defect. These findings are consistent with a conserved role for ETC-1 in promoting proteasome processivity and suggest that proteasomal processivity is an important element of the oocyte-to-embryo transition during which many key oocyte regulatory proteins are rapidly targeted for degradation.

  PublisherOA PDFDOI

Recent grants

• NIH Grant S10RR026341

  NIH · $409k · 2012

• NIH Grant R56GM057173

  NIH · $310k · 2009

• Control of Meiosis and Germline Proliferation

  NIH · $6.9M · 1998–2023

• Using the C. elegans Oocyte to Model the Cell Biology of Early Onset Dystonia

  NIH · $418k · 2015–2018

• The C. elegans Germline: A Test Tube for Cell and Developmental Biology

  NIH · $2.1M · 2022–2027

Frequent coauthors

• Kensuke Horiuchi

  Rockefeller University

  19 shared

• Atsushi Higashitani

  Tohoku University

  17 shared

• Hideo Hirokawa

  Sophia University

  16 shared

• S Asano

  16 shared

• Caroline A. Spike

  University of Minnesota

  11 shared

• Tatsuya Tsukamoto

  University of Minnesota

  9 shared

• Gabriela Huelgas‐Morales

  Mays Cancer Center at UT Health San Antonio

  8 shared

• J. Amaranath Govindan

  Massachusetts General Hospital

  8 shared