Uchida, A;Imaimatsu, K;Suzuki, H;Han, X;Ushioda, H;Uemura, M;Imura-Kishi, K;Hiramatsu, R;Takase, HM;Hirate, Y;Ogura, A;Kanai-Azuma, M;Kudo, A;Kanai, Y;
PMID: 36543770 | DOI: 10.1038/s41467-022-35465-1
Seminiferous tubules (STs) in the mammalian testes are connected to the rete testis (RT) via a Sertoli valve (SV). Spermatozoa produced in the STs are released into the tubular luminal fluid and passively transported through the SV into the RT. However, the physiological functions of the RT and SV remain unclear. Here, we identified the expression of Sox17 in RT epithelia. The SV valve was disrupted before puberty in RT-specific Sox17 conditional knockout (Sox17-cKO) male mice. This induced a backflow of RT fluid into the STs, which caused aberrant detachment of immature spermatids. RT of Sox17-cKO mice had reduced expression levels of various growth factor genes, which presumably support SV formation. When transplanted next to the Sox17+ RT, Sertoli cells of Sox17-cKO mice reconstructed the SV and supported proper spermiogenesis in the STs. This study highlights the novel and unexpected modulatory roles of the RT in SV valve formation and spermatogenesis in mouse testes, as a downstream action of Sox17.
Taylor, R;Hamid, F;Fielding, T;Gordon, PM;Maloney, M;Makeyev, EV;Houart, C;
PMID: 36414621 | DOI: 10.1038/s41467-022-34331-4
Loss of SFPQ is a hallmark of motor degeneration in ALS and prevents maturation of motor neurons when occurring during embryogenesis. Here, we show that in zebrafish, developing motor neurons lacking SFPQ exhibit axon extension, branching and synaptogenesis defects, prior to degeneration. Subcellular transcriptomics reveals that loss of SFPQ in neurons produces a complex set of aberrant intron-retaining (IR) transcripts coding for neuron-specific proteins that accumulate in neurites. Some of these local IR mRNAs are prematurely terminated within the retained intron (PreT-IR). PreT-IR mRNAs undergo intronic polyadenylation, nuclear export, and localise to neurites in vitro and in vivo. We find these IR and PreT-IR mRNAs enriched in RNAseq datasets of tissue from patients with familial and sporadic ALS. This shared signature, between SFPQ-depleted neurons and ALS, functionally implicates SFPQ with the disease and suggests that neurite-centred perturbation of alternatively spliced isoforms drives the neurodegenerative process.
Jablonska, B;Adams, KL;Kratimenos, P;Li, Z;Strickland, E;Haydar, TF;Kusch, K;Nave, KA;Gallo, V;
PMID: 35970992 | DOI: 10.1038/s41467-022-32462-2
Delayed oligodendrocyte (OL) maturation caused by hypoxia (Hx)-induced neonatal brain injury results in hypomyelination and leads to neurological disabilities. Previously, we characterized Sirt1 as a crucial regulator of OL progenitor cell (OPC) proliferation in response to Hx. We now identify Sirt2 as a critical promoter of OL differentiation during both normal white matter development and in a mouse model of Hx. Importantly, we find that Hx reduces Sirt2 expression in mature OLs and that Sirt2 overexpression in OPCs restores mature OL populations. Reduced numbers of Sirt2+ OLs were also observed in the white matter of preterm human infants. We show that Sirt2 interacts with p27Kip1/FoxO1, p21Cip1/Cdk4, and Cdk5 pathways, and that these interactions are altered by Hx. Furthermore, Hx induces nuclear translocation of Sirt2 in OPCs where it binds several genomic targets. Overall, these results indicate that a balance of Sirt1 and Sirt2 activity is required for developmental oligodendrogenesis, and that these proteins represent potential targets for promoting repair following white matter injury.
Lindholm, HT;Parmar, N;Drurey, C;Campillo Poveda, M;Vornewald, PM;Ostrop, J;Díez-Sanchez, A;Maizels, RM;Oudhoff, MJ;
PMID: 35559665 | DOI: 10.1126/sciimmunol.abl6543
The intestinal tract is a common site for various types of infections including viruses, bacteria, and helminths, each requiring specific modes of immune defense. The intestinal epithelium has a pivotal role in both immune initiation and effector stages, which are coordinated by lymphocyte cytokines such as IFNγ, IL-13, and IL-22. Here, we studied intestinal epithelial immune responses using organoid image analysis based on a convolutional neural network, transcriptomic analysis, and in vivo infection models. We found that IL-13 and IL-22 both induce genes associated with goblet cells, but the resulting goblet cell phenotypes are dichotomous. Moreover, only IL-13-driven goblet cells are associated with classical NOTCH signaling. We further showed that IL-13 induces the bone morphogenetic protein (BMP) pathway, which acts in a negative feedback loop on immune type 2-driven tuft cell hyperplasia. This is associated with inhibiting Sox4 expression to putatively limit the tuft cell progenitor population. Blocking ALK2, a BMP receptor, with the inhibitor dorsomorphin homolog 1 (DMH1) interrupted the feedback loop, resulting in greater tuft cell numbers both in vitro and in vivo after infection with Nippostrongylus brasiliensis. Together, this investigation of cytokine effector responses revealed an unexpected and critical role for the BMP pathway in regulating type 2 immunity, which can be exploited to tailor epithelial immune responses.
Clayton, SW;Angermeier, A;Halbrooks, JE;McCardell, R;Serra, R;
PMID: 35644252 | DOI: 10.1016/j.ydbio.2022.05.013
We previously showed the importance of TGFβ signaling in development of the mouse axial skeleton. Here, we provide the first direct evidence that TGFβ signaling is required for resegmentation of the sclerotome using chick embryos. Lipophilic fluorescent tracers, DiO and DiD, were microinjected into adjacent somites of embryos treated with or without TGFβRI inhibitors, SB431542, SB525334 or SD208, at developmental day E2.5 (HH16). Lineage tracing of labeled cells was observed over the course of 4 days until the completion of resegmentation at E6.5 (HH32). Vertebrae were malformed and intervertebral discs were small and misshapen in inhibitor injected embryos. Hypaxial myofibers were also increased in thickness after treatment with the inhibitor. Inhibition of TGFβ signaling resulted in alterations in resegmentation that ranged between full, partial, and slanted shifts in distribution of DiO or DiD labeled cells within vertebrae. Patterning of rostro-caudal markers within sclerotome was disrupted at E3.5 after treatment with TGFβRI inhibitor with rostral domains expressing both rostral and caudal markers. We propose that TGFβ signaling regulates rostro-caudal polarity and subsequent resegmentation in sclerotome during spinal column development.
Chen, K;Wang, P;Chen, J;Ying, Y;Chen, Y;Gilson, E;Lu, Y;Ye, J;
PMID: 35203601 | DOI: 10.3390/biomedicines10020392
Ataxia-telangiectasia mutated (ATM) is a key DNA damage signaling kinase that is mutated in humans with ataxia-telangiectasia (A-T) syndrome. This syndrome is characterized by neurodegeneration, immune abnormality, cancer predisposition, and premature aging. To better understand the function of ATM in vivo, we engineered a viable zebrafish model with a mutated atm gene. Zebrafish atm loss-of-function mutants show characteristic features of A-T-like motor disturbance, including coordination disorders, immunodeficiency, and tumorigenesis. The immunological disorder of atm homozygote fish is linked to the developmental blockade of hematopoiesis, which occurs at the adulthood stage and results in a decrease in infection defense but, with little effect on wound healing. Malignant neoplasms found in atm mutant fish were mainly nerve sheath tumors and myeloid leukemia, which rarely occur in A-T patients or Atm-/- mice. These results underscore the importance of atm during immune cell development. This zebrafish A-T model opens up a pathway to an improved understanding of the molecular basis of tumorigenesis in A-T and the cellular role of atm.
International Journal for Parasitology: Drugs and Drug Resistance
Choudhary, S;Kashyap, S;Martin, R;Robertson, A;
| DOI: 10.1016/j.ijpddr.2021.12.001
Ion channels are specialized multimeric proteins that underlie cell excitability. These channels integrate with a variety of neuromuscular and biological functions. In nematodes, the physiological behaviors including locomotion, navigation, feeding and reproduction, are regulated by these protein entities. Majority of the antinematodal chemotherapeutics target the ion channels to disrupt essential biological functions. Here, we have summarized current advances in our understanding of nematode ion channel pharmacology. We review cys-loop ligand gated ion channels (LGICs), including nicotinic acetylcholine receptors (nAChRs), acetylcholine-chloride gated ion channels (ACCs), glutamate-gated chloride channels (GluCls), and GABA (γ-aminobutyric acid) receptors, and other ionotropic receptors (transient receptor potential (TRP) channels and potassium ion channels). We have provided an update on the pharmacological properties of these channels from various nematodes. This article catalogs the differences in ion channel composition and resulting pharmacology in the phylum Nematoda. This diversity in ion channel subunit repertoire and pharmacology emphasizes the importance of pursuing species-specific drug target research. In this review, we have provided an overview of recent advances in techniques and functional assays available for screening ion channel properties and their application.
A neuroanatomical mechanism linking perinatal TCDD exposure to lower urinary tract dysfunction in adulthood
Disease models & mechanisms
Turco, AE;Oakes, SR;Stietz, KPK;Dunham, CL;Joseph, DB;Chathurvedula, TS;Girardi, NM;Schneider, AJ;Gawdzik, J;Sheftel, CM;Wang, P;Wang, Z;Bjorling, DE;Ricke, WA;Tang, W;Hernandez, LL;Keast, JR;Bonev, AD;Grimes, MD;Strand, DW;Tykocki, NR;Tanguay, RL;Peterson, RE;Vezina, CM;
PMID: 34164643 | DOI: 10.1242/dmm.049068
Benign Prostatic Hyperplasia / Lower Urinary Tract Dysfunction (BPH/LUTD) is a classic disease of aging which affects nearly all men. Symptoms typically present in the fifth or sixth decade and progressively worsen over the remainder of life. Here, we identify a surprising origin of this disease that traces back to the intrauterine environment of the developing male, challenging existing paradigms about when this disease process begins. We delivered a single bolus dose of a widespread environmental contaminant, present in the serum of most Americans (2,3,7,8 tetrachlorodibenzo-p-dioxin, TCDD, 1 µg/kg), and representative of a broader class of environmental contaminants, to pregnant mice and observed an increase in the abundance of a neurotrophic factor, artemin, in the developing mouse prostate. Artemin is required for noradrenergic axon recruitment across multiple tissues and TCDD rapidly increases prostatic noradrenergic axon density in the male fetus. The hyperinnervation does not resolve, but rather persists into adulthood, when it is coupled to autonomic hyperactivity of prostatic smooth muscle and abnormal urinary function, including increased urinary frequency, a bothersome symptom in men. We offer new evidence that prostate neuroanatomical development is malleable and that intrauterine chemical exposures can permanently reprogram prostate neuromuscular function to cause male LUTD in adulthood.
Folorunso, OO;Brown, SE;Baruah, J;Harvey, TL;Jami, SA;Radzishevsky, I;Wolosker, H;McNally, JM;Gray, JA;Vasudevan, A;Balu, DT;
PMID: 37311798 | DOI: 10.1038/s41598-023-35615-5
The proper development and function of telencephalic GABAergic interneurons is critical for maintaining the excitation and inhibition (E/I) balance in cortical circuits. Glutamate contributes to cortical interneuron (CIN) development via N-methyl-D-aspartate receptors (NMDARs). NMDAR activation requires the binding of a co-agonist, either glycine or D-serine. D-serine (co-agonist at many mature forebrain synapses) is racemized by the neuronal enzyme serine racemase (SR) from L-serine. We utilized constitutive SR knockout (SR-/-) mice to investigate the effect of D-serine availability on the development of CINs and inhibitory synapses in the prelimbic cortex (PrL). We found that most immature Lhx6 + CINs expressed SR and the obligatory NMDAR subunit NR1. At embryonic day 15, SR-/- mice had an accumulation of GABA and increased mitotic proliferation in the ganglionic eminence and fewer Gad1 + (glutamic acid decarboxylase 67 kDa; GAD67) cells in the E18 neocortex. Lhx6 + cells develop into parvalbumin (PV+) and somatostatin (Sst+) CINs. In the PrL of postnatal day (PND) 16 SR-/- mice, there was a significant decrease in GAD67+ and PV+, but not SST + CIN density, which was associated with reduced inhibitory postsynaptic potentials in layer 2/3 pyramidal neurons. These results demonstrate that D-serine availability is essential for prenatal CIN development and postnatal cortical circuit maturation.
Cheung, LYM;Menage, L;Rizzoti, K;Hamilton, G;Dumontet, T;Basham, K;Daly, AZ;Brinkmeier, ML;Masser, BE;Treier, M;Cobb, J;Delogu, A;Lovell-Badge, R;Hammer, GD;Camper, SA;
PMID: 37183548 | DOI: 10.1210/endocr/bqad076
The pituitary gland regulates growth, metabolism, reproduction, the stress response, uterine contractions, lactation, and water retention. It secretes hormones in response to hypothalamic input, end organ feedback, and diurnal cues. The mechanisms by which pituitary stem cells are recruited to proliferate, maintain quiescence or differentiate into specific cell types, especially thyrotropes, are not well understood. We utilized single-cell RNA sequencing in juvenile P7 mouse pituitary cells to identify novel factors in pituitary cell populations, with a focus on thyrotropes and rare subtypes. We first observed cells co-expressing markers of both thyrotropes and gonadotropes, such as Pou1f1 and Nr5a1. This was validated in vivo by both immunohistochemistry and lineage tracing of thyrotropes derived from Nr5a1-Cre; mTmG mice and demonstrates that Nr5a1-progenitors give rise to a proportion of thyrotropes during development. Our dataset also identifies novel factors expressed in pars distalis and pars tuberalis thyrotropes, including the Shox2b isoform in all thyrotropes and Sox14 specifically in Pou1f1-negative pars tuberalis thyrotropes. We have therefore used single-cell transcriptomics to determine a novel developmental trajectory for thyrotropes and potential novel regulators of thyrotrope populations.
Developmental dynamics : an official publication of the American Association of Anatomists
Kasemeier-Kulesa, JC;Morrison, JA;McKinney, S;Li, H;Gogol, M;Hall, K;Chen, S;Wang, Y;Perera, A;McLennan, R;Kulesa, PM;
PMID: 36840366 | DOI: 10.1002/dvdy.577
The molecular identification of neural progenitor cell populations that connect to establish the sympathetic nervous system (SNS) remains unclear. This is due to technical limitations in the acquisition and spatial mapping of molecular information to tissue architecture.To address this, we applied Slide-seq spatial transcriptomics to intact fresh frozen chick trunk tissue transversely cryo-sectioned at the developmental stage prior to SNS formation. In parallel, we performed age- and location-matched single cell (sc) RNA-seq and 10× Genomics Visium to inform our analysis. Downstream bioinformatic analyses led to the unique molecular identification of neural progenitor cells within the peripheral sympathetic ganglia (SG) and spinal cord preganglionic neurons (PGNs). We then successfully applied the HiPlex RNAscope fluorescence in situ hybridization and multispectral confocal microscopy to visualize 12 gene targets in stage-, age- and location-matched chick trunk tissue sections.Together, these data demonstrate a robust strategy to acquire and integrate single cell and spatial transcriptomic information, resulting in improved resolution of molecular heterogeneities in complex neural tissue architectures. Successful application of this strategy to the developing SNS provides a roadmap for functional studies of neural connectivity and platform to address complex questions in neural development and regeneration.
Childs, CJ;Holloway, EM;Sweet, CW;Tsai, YH;Wu, A;Vallie, A;Eiken, MK;Capeling, MM;Zwick, RK;Palikuqi, B;Trentesaux, C;Wu, JH;Pellon-Cardenas, O;Zhang, CJ;Glass, IA;Loebel, C;Yu, Q;Camp, JG;Sexton, JZ;Klein, OD;Verzi, MP;Spence, JR;
PMID: 36821371 | DOI: 10.1172/jci.insight.165566
Epithelial organoids derived from intestinal tissue, called 'enteroids', recapitulate many aspects of the organ in vitro, and can be used for biological discovery, personalized medicine, and drug development. Here, we interrogated the cell signaling environment within the developing human intestine to identify niche cues that may be important for epithelial development and homeostasis. We identify an EGF family member, EPIREGULIN (EREG), which is robustly expressed in the developing human crypt. Enteroids generated from the developing human intestine grown in standard culture conditions, which contain EGF, are dominated by stem and progenitor cells, feature little differentiation and no spatial organization. Our results demonstrate that EREG can replace EGF in vitro, and EREG leads to spatially resolved enteroids that feature budded and proliferative crypt domains and a differentiated villus-like central lumen. Multiomic (transcriptome plus epigenome) profiling of native crypts, EGF-grown and EREG-grown enteroids show that EGF-enteroids have an altered chromatin landscape that is dependent on EGF concentration, downregulate the master intestinal transcription factor CDX2, and ectopically express stomach genes, a phenomenon that is reversible. This is in contrast to EREG-grown enteroids, which remain intestine-like in culture. Thus, EREG creates a homeostatic intestinal niche in vitro, enabling interrogation of stem cell function, cellular differentiation, and disease modeling.