Neurosciences Commons^™

Cerebellar Dysfunction As A Source Of Dystonic Phenotypes In Mice, Amanda M Brown, Meike E Van Der Heijden, H A Jinnah, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

There is now a substantial amount of compelling evidence demonstrating that the cerebellum may be a central locus in dystonia pathogenesis. Studies using spontaneous genetic mutations in rats and mice, engineered genetic alleles in mice, shRNA knockdown in mice, and conditional genetic silencing of fast neurotransmission in mice have all uncovered a common set of behavioral and electrophysiological defects that point to cerebellar cortical and cerebellar nuclei dysfunction as a source of dystonic phenotypes. Here, we revisit the Ptf1aCre/+;Vglut2flox/flox mutant mouse to define fundamental phenotypes and measures that are valuable for testing the cellular, circuit, and …

Metastatic Infiltration Of Nervous Tissue And Periosteal Nerve Sprouting In Multiple Myeloma-Induced Bone Pain In Mice And Human, Marta Diaz-Delcastillo, Oana Palasca, Tim T Nemler, Didde M Thygesen, Norma A Chávez-Saldaña, Juan A Vázquez-Mora, Lizeth Y Ponce Gomez, Lars Juhl Jensen, Holly Evans, Rebecca E Andrews, Aritri Mandal, David Neves, Patrick Mehlen, James P Caruso, Patrick M Dougherty, Theodore J Price, Andrew Chantry, Michelle A Lawson, Thomas L Andersen, Juan M Jimenez-Andrade, Anne-Marie Heegaard

Faculty, Staff and Student Publications

Multiple myeloma (MM) is a neoplasia of B plasma cells that often induces bone pain. However, the mechanisms underlying myeloma-induced bone pain (MIBP) are mostly unknown. Using a syngeneic MM mouse model, we show that periosteal nerve sprouting of calcitonin gene-related peptide (CGRP+) and growth associated protein 43 (GAP43+) fibers occurs concurrent to the onset of nociception and its blockade provides transient pain relief. MM patient samples also showed increased periosteal innervation. Mechanistically, we investigated MM induced gene expression changes in the dorsal root ganglia (DRG) innervating the MM-bearing bone of male mice and found alterations in pathways associated with …

Metastatic Infiltration Of Nervous Tissue And Periosteal Nerve Sprouting In Multiple Myeloma-Induced Bone Pain In Mice And Human, Marta Diaz-Delcastillo, Oana Palasca, Tim T Nemler, Didde M Thygesen, Norma A Chávez-Saldaña, Juan A Vázquez-Mora, Lizeth Y Ponce Gomez, Lars Juhl Jensen, Holly Evans, Rebecca E Andrews, Aritri Mandal, David Neves, Patrick Mehlen, James P Caruso, Patrick M Dougherty, Theodore J Price, Andrew Chantry, Michelle A Lawson, Thomas L Andersen, Juan M Jimenez-Andrade, Anne-Marie Heegaard

Faculty, Staff and Student Publications

Multiple myeloma (MM) is a neoplasia of B plasma cells that often induces bone pain. However, the mechanisms underlying myeloma-induced bone pain (MIBP) are mostly unknown. Using a syngeneic MM mouse model, we show that periosteal nerve sprouting of calcitonin gene-related peptide (CGRP+) and growth associated protein 43 (GAP43+) fibers occurs concurrent to the onset of nociception and its blockade provides transient pain relief. MM patient samples also showed increased periosteal innervation. Mechanistically, we investigated MM induced gene expression changes in the dorsal root ganglia (DRG) innervating the MM-bearing bone of male mice and found alterations in pathways associated with …

Βii-Spectrin Is Required For Synaptic Positioning During Retinal Development, Debalina Goswami-Sewell, Caitlin Bagnetto, Cesiah C Gomez, Joseph T Anderson, Akash Maheshwari, Elizabeth Zuniga-Sanchez

Faculty, Staff and Students Publications

Neural circuit assembly is a multistep process where synaptic partners are often born at distinct developmental stages, and yet they must find each other and form precise synaptic connections with one another. This developmental process often relies on late-born neurons extending their processes to the appropriate layer to find and make synaptic connections to their early-born targets. The molecular mechanism responsible for the integration of late-born neurons into an emerging neural circuit remains unclear. Here, we uncovered a new role for the cytoskeletal protein βII-spectrin in properly positioning presynaptic and postsynaptic neurons to the developing synaptic layer. Loss of βII-spectrin …

Anoctamin 4 Channel Currents Activate Glucose-Inhibited Neurons In The Mouse Ventromedial Hypothalamus During Hypoglycemia, Longlong Tu, Jonathan C Bean, Yang He, Hailan Liu, Meng Yu, Hesong Liu, Nan Zhang, Na Yin, Junying Han, Nikolas A Scarcelli, Kristine M Conde, Mengjie Wang, Yongxiang Li, Bing Feng, Peiyu Gao, Zhao-Lin Cai, Makoto Fukuda, Mingshan Xue, Qingchun Tong, Yongjie Yang, Lan Liao, Jianming Xu, Chunmei Wang, Yanlin He, Yong Xu

Faculty, Staff and Student Publications

Glucose is the basic fuel essential for maintenance of viability and functionality of all cells. However, some neurons - namely, glucose-inhibited (GI) neurons - paradoxically increase their firing activity in low-glucose conditions and decrease that activity in high-glucose conditions. The ionic mechanisms mediating electric responses of GI neurons to glucose fluctuations remain unclear. Here, we showed that currents mediated by the anoctamin 4 (Ano4) channel are only detected in GI neurons in the ventromedial hypothalamic nucleus (VMH) and are functionally required for their activation in response to low glucose. Genetic disruption of the Ano4 gene in VMH neurons reduced blood …

The Cerebellum Contributes To Generalized Seizures By Altering Activity In The Ventral Posteromedial Nucleus, Jaclyn Beckinghausen, Joshua Ortiz-Guzman, Tao Lin, Benjamin Bachman, Luis E Salazar Leon, Yu Liu, Detlef H Heck, Benjamin R Arenkiel, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Thalamo-cortical networks are central to seizures, yet it is unclear how these circuits initiate seizures. We test whether a facial region of the thalamus, the ventral posteromedial nucleus (VPM), is a source of generalized, convulsive motor seizures and if convergent VPM input drives the behavior. To address this question, we devise an in vivo optogenetic mouse model to elicit convulsive motor seizures by driving these inputs and perform single-unit recordings during awake, convulsive seizures to define the local activity of thalamic neurons before, during, and after seizure onset. We find dynamic activity with biphasic properties, raising the possibility that heterogenous …

Targeting Gbm With An Oncolytic Picornavirus Svv-001 Alone And In Combination With Fractionated Radiation In A Novel Panel Of Orthotopic Pdx Models, Huiyuan Zhang, Yuchen Du, Lin Qi, Sophie Xiao, Frank K Braun, Mari Kogiso, Yulun Huang, Frank Huang, Aalaa Abdallah, Milagros Suarez, Sekar Karthick, Nabil M Ahmed, Vita S Salsman, Patricia A Baxter, Jack M Su, Daniel J Brat, Paul L Hellenbeck, Wan-Yee Teo, Akash J Patel, Xiao-Nan Li

Faculty, Staff and Students Publications

BACKGROUND: Animal models representing different molecular subtypes of glioblastoma multiforme (GBM) is desired for developing new therapies. SVV-001 is an oncolytic virus selectively targeting cancer cells. It's capacity of passing through the blood brain barrier makes is an attractive novel approach for GBM.

MATERIALS AND METHODS: 23 patient tumor samples were implanted into the brains of NOD/SCID mice (1 × 105 cells/mouse). Tumor histology, gene expression (RNAseq), and growth rate of the developed patient-derived orthotopic xenograft (PDOX) models were compared with the originating patient tumors during serial subtransplantations. Anti-tumor activities of SVV-001 were examined in vivo; and therapeutic efficacy validated …

Targeting Aav Vectors To The Central Nervous System By Engineering Capsid-Receptor Interactions That Enable Crossing Of The Blood-Brain Barrier, Qin Huang, Albert T Chen, Ken Y Chan, Hikari Sorensen, Andrew J Barry, Bahar Azari, Qingxia Zheng, Thomas Beddow, Binhui Zhao, Isabelle G Tobey, Cynthia Moncada-Reid, Fatma-Elzahraa Eid, Christopher J Walkey, M Cecilia Ljungberg, William R Lagor, Jason D Heaney, Yujia A Chan, Benjamin E Deverman

Faculty, Staff and Students Publications

Viruses have evolved the ability to bind and enter cells through interactions with a wide variety of cell macromolecules. We engineered peptide-modified adeno-associated virus (AAV) capsids that transduce the brain through the introduction of de novo interactions with 2 proteins expressed on the mouse blood-brain barrier (BBB), LY6A or LY6C1. The in vivo tropisms of these capsids are predictable as they are dependent on the cell- and strain-specific expression of their target protein. This approach generated hundreds of capsids with dramatically enhanced central nervous system (CNS) tropisms within a single round of screening in vitro and secondary validation in vivo …

Reprogramming Tumour-Associated Macrophages To Outcompete Cancer Cells, Xian Zhang, Shun Li, Isha Malik, Mytrang H Do, Liangliang Ji, Chun Chou, Wei Shi, Kristelle J Capistrano, Jing Zhang, Ting-Wei Hsu, Briana G Nixon, Ke Xu, Xinxin Wang, Andrea Ballabio, Laura S Schmidt, W Marston Linehan, Ming O Li

Duncan NRI Faculty and Staff Publications

In metazoan organisms, cell competition acts as a quality control mechanism to eliminate unfit cells in favour of their more robust neighbours1,2. This mechanism has the potential to be maladapted, promoting the selection of aggressive cancer cells3-6. Tumours are metabolically active and are populated by stroma cells7,8, but how environmental factors affect cancer cell competition remains largely unknown. Here we show that tumour-associated macrophages (TAMs) can be dietarily or genetically reprogrammed to outcompete MYC-overexpressing cancer cells. In a mouse model of breast cancer, MYC overexpression resulted in an mTORC1-dependent 'winner' cancer cell state. A low-protein diet inhibited mTORC1 signalling in …

Cortex-Wide Neural Dynamics Predict Behavioral States And Provide A Neural Basis For Resting-State Dynamic Functional Connectivity, Somayeh Shahsavarani, David N Thibodeaux, Weihao Xu, Sharon H Kim, Fatema Lodgher, Chinwendu Nwokeabia, Morgan Cambareri, Alexis J Yagielski, Hanzhi T Zhao, Daniel A Handwerker, Javier Gonzalez-Castillo, Peter A Bandettini, Elizabeth M C Hillman

Faculty, Staff and Student Publications

Although resting-state functional magnetic resonance imaging (fMRI) studies have observed dynamically changing brain-wide networks of correlated activity, fMRI's dependence on hemodynamic signals makes results challenging to interpret. Meanwhile, emerging techniques for real-time recording of large populations of neurons have revealed compelling fluctuations in neuronal activity across the brain that are obscured by traditional trial averaging. To reconcile these observations, we use wide-field optical mapping to simultaneously record pan-cortical neuronal and hemodynamic activity in awake, spontaneously behaving mice. Some components of observed neuronal activity clearly represent sensory and motor function. However, particularly during quiet rest, strongly fluctuating patterns of activity across …

Sox7 Deficiency Causes Ventricular Septal Defects Through Its Effects On Endocardial-To-Mesenchymal Transition And The Expression Of Wnt4 And Bmp2, Andrés Hernández-García, Katherine E Pendleton, Sangbae Kim, Yumei Li, Bum J Kim, Hitisha P Zaveri, Valerie K Jordan, Aliska M Berry, M Cecilia Ljungberg, Rui Chen, Rainer B Lanz, Daryl A Scott

Faculty, Staff and Students Publications

SOX7 is a transcription factor-encoding gene located in a region on chromosome 8p23.1 that is recurrently deleted in individuals with ventricular septal defects (VSDs). We have previously shown that Sox7-/- embryos die of heart failure around E11.5. Here, we demonstrate that these embryos have hypocellular endocardial cushions with severely reduced numbers of mesenchymal cells. Ablation of Sox7 in the endocardium also resulted in hypocellular endocardial cushions, and we observed VSDs in rare E15.5 Sox7flox/-;Tie2-Cre and Sox7flox/flox;Tie2-Cre embryos that survived to E15.5. In atrioventricular explant studies, we showed that SOX7 deficiency leads to a severe reduction in endocardial-to-mesenchymal transition (EndMT). RNA-seq …

Induction Of Astrocytic Slc22a3 Regulates Sensory Processing Through Histone Serotonylation, Debosmita Sardar, Yi-Ting Cheng, Junsung Woo, Dong-Joo Choi, Zhung-Fu Lee, Wookbong Kwon, Hsiao-Chi Chen, Brittney Lozzi, Alexis Cervantes, Kavitha Rajendran, Teng-Wei Huang, Antrix Jain, Benjamin R Arenkiel, Ian Maze, Benjamin Deneen

Faculty, Staff and Students Publications

Neuronal activity drives alterations in gene expression within neurons, yet how it directs transcriptional and epigenomic changes in neighboring astrocytes in functioning circuits is unknown. We found that neuronal activity induces widespread transcriptional upregulation and downregulation in astrocytes, highlighted by the identification of a neuromodulator transporter Slc22a3 as an activity-inducible astrocyte gene regulating sensory processing in the olfactory bulb. Loss of astrocytic Slc22a3 reduced serotonin (5HT) levels in astrocytes, leading to alterations in histone serotonylation. Inhibition of histone serotonylation in astrocytes reduced expression of GABA biosynthetic genes and GABA release, culminating in olfactory deficits. Our study revealed that neuronal activity …

Complement C3ar Depletion Reverses Hif-1Α-Induced Metabolic Impairment And Enhances Microglial Response To Aβ Pathology, Manasee Gedam, Michele M Comerota, Nicholas E Propson, Tao Chen, Feng Jin, Meng C Wang, Hui Zheng

Faculty, Staff and Students Publications

Microglia are the major cell type expressing complement C3a receptor (C3aR) in the brain. Using a knockin mouse line in which a Td-tomato reporter is incorporated into the endogenous C3ar1 locus, we identified 2 major subpopulations of microglia with differential C3aR expression. Expressing the Td-tomato reporter on the APPNL-G-F-knockin (APP-KI) background revealed a significant shift of microglia to a high-C3aR-expressing subpopulation and they were enriched around amyloid β (Aβ) plaques. Transcriptomic analysis of C3aR-positive microglia documented dysfunctional metabolic signatures, including upregulation of hypoxia-inducible factor 1 (HIF-1) signaling and abnormal lipid metabolism in APP-KI mice compared with wild-type controls. Using primary …

Chronic Basal Forebrain Activation Improves Spatial Memory, Boosts Neurotrophin Receptor Expression, And Lowers Bace1 And Aβ42 Levels In The Cerebral Cortex In Mice, Jacob Kumro, Ashutosh Tripathi, Yun Lei, Jeremy Sword, Patrick Callahan, Alvin Terry, Xin-Yun Lu, Sergei A Kirov, Anilkumar Pillai, David T Blake

Faculty, Staff and Student Publications

The etiology of Alzheimer’s dementia has been hypothesized in terms of basal forebrain cholinergic decline, and in terms of reflecting beta-amyloid neuropathology. To study these different biological elements, we activated the basal forebrain in 5xFAD Alzheimer’s model mice and littermates. Mice received 5 months of 1 h per day intermittent stimulation of the basal forebrain, which includes cholinergic projections to the cortical mantle. Then, mice were behaviorally tested followed by tissue analysis. The 5xFAD mice performed worse in water-maze testing than littermates. Stimulated groups learned the water maze better than unstimulated groups. Stimulated groups had 2–3-fold increases in frontal cortex …

Membrane Compression By Synaptic Vesicle Exocytosis Triggers Ultrafast Endocytosis, Tyler H Ogunmowo, Haoyuan Jing, Sumana Raychaudhuri, Grant F Kusick, Yuuta Imoto, Shuo Li, Kie Itoh, Ye Ma, Haani Jafri, Matthew B. Dalva, Edwin R Chapman, Taekjip Ha, Shigeki Watanabe, Jian Liu

Department of Neuroscience Faculty Papers

Compensatory endocytosis keeps the membrane surface area of secretory cells constant following exocytosis. At chemical synapses, clathrin-independent ultrafast endocytosis maintains such homeostasis. This endocytic pathway is temporally and spatially coupled to exocytosis; it initiates within 50 ms at the region immediately next to the active zone where vesicles fuse. However, the coupling mechanism is unknown. Here, we demonstrate that filamentous actin is organized as a ring, surrounding the active zone at mouse hippocampal synapses. Assuming the membrane area conservation is due to this actin ring, our theoretical model suggests that flattening of fused vesicles exerts lateral compression in the plasma …

Glutamatergic Cerebellar Neurons Differentially Contribute To The Acquisition Of Motor And Social Behaviors, Meike E Van Der Heijden, Alejandro G Rey Hipolito, Linda H Kim, Dominic J Kizek, Ross M Perez, Tao Lin, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Insults to the developing cerebellum can cause motor, language, and social deficits. Here, we investigate whether developmental insults to different cerebellar neurons constrain the ability to acquire cerebellar-dependent behaviors. We perturb cerebellar cortical or nuclei neuron function by eliminating glutamatergic neurotransmission during development, and then we measure motor and social behaviors in early postnatal and adult mice. Altering cortical and nuclei neurons impacts postnatal motor control and social vocalizations. Normalizing neurotransmission in cortical neurons but not nuclei neurons restores social behaviors while the motor deficits remain impaired in adults. In contrast, manipulating only a subset of nuclei neurons leaves social …

Efficient Cancer Modeling Through Crispr-Cas9/Hdr-Based Somatic Precision Gene Editing In Mice, Wen Bu, Chad J Creighton, Kelsey S Heavener, Carolina Gutierrez, Yongchao Dou, Amy T Ku, Yiqun Zhang, Weiyu Jiang, Jazmin Urrutia, Wen Jiang, Fei Yue, Luyu Jia, Ahmed Atef Ibrahim, Bing Zhang, Shixia Huang, Yi Li

Faculty, Staff and Student Publications

CRISPR-Cas9 has been used successfully to introduce indels in somatic cells of rodents; however, precise editing of single nucleotides has been hampered by limitations of flexibility and efficiency. Here, we report technological modifications to the CRISPR-Cas9 vector system that now allows homology-directed repair-mediated precise editing of any proto-oncogene in murine somatic tissues to generate tumor models with high flexibility and efficiency. Somatic editing of either

Functional Neuronal Circuits Promote Disease Progression In Cancer, Anthony C Restaino, Austin Walz, Samuel J Vermeer, Jeffrey Barr, Attila Kovács, Robin R Fettig, Daniel W Vermeer, Hunter Reavis, Caitlin S Williamson, Christopher T Lucido, Tuany Eichwald, Dalia K Omran, Euihye Jung, Lauren E Schwartz, Maria Bell, Desirae M Muirhead, Jody E Hooper, William C Spanos, Ronny Drapkin, Sebastien Talbot, Paola D Vermeer

Faculty, Staff and Student Publications

The molecular and functional contributions of intratumoral nerves to disease remain largely unknown. We localized synaptic markers within tumors suggesting that these nerves form functional connections. Consistent with this, electrophysiological analysis shows that malignancies harbor significantly higher electrical activity than benign disease or normal tissues. We also demonstrate pharmacologic silencing of tumoral electrical activity. Tumors implanted in transgenic animals lacking nociceptor neurons show reduced electrical activity. These data suggest that intratumoral nerves remain functional at the tumor bed. Immunohistochemical staining demonstrates the presence of the neuropeptide, Substance P (SP), within the tumor space. We show that tumor cells express the …

Tfeb And Tfe3 Drive Kidney Cystogenesis And Tumorigenesis, Chiara Di Malta, Angela Zampelli, Letizia Granieri, Claudia Vilardo, Rossella De Cegli, Laura Cinque, Edoardo Nusco, Salvatore Pece, Daniela Tosoni, Francesca Sanguedolce, Nicolina Cristina Sorrentino, Maria J Merino, Deborah Nielsen, Ramaprasad Srinivasan, Mark W Ball, Christopher J Ricketts, Cathy D Vocke, Martin Lang, Baktiar Karim, Luisa Lanfrancone, Laura S Schmidt, W Marston Linehan, Andrea Ballabio

Duncan NRI Faculty and Staff Publications

Birt-Hogg-Dubé (BHD) syndrome is an inherited familial cancer syndrome characterized by the development of cutaneous lesions, pulmonary cysts, renal tumors and cysts and caused by loss-of-function pathogenic variants in the gene encoding the tumor-suppressor protein folliculin (FLCN). FLCN acts as a negative regulator of TFEB and TFE3 transcription factors, master controllers of lysosomal biogenesis and autophagy, by enabling their phosphorylation by the mechanistic Target Of Rapamycin Complex 1 (mTORC1). We have previously shown that deletion of Tfeb rescued the renal cystic phenotype of kidney-specific Flcn KO mice. Using Flcn/Tfeb/Tfe3 double and triple KO mice, we now show that both Tfeb …

Tmem106b Regulates Microglial Proliferation And Survival In Response To Demyelination, Tingting Zhang, Weilun Pang, Tuancheng Feng, Jennifer Guo, Kenton Wu, Mariela Nunez Santos, Akshayakeerthi Arthanarisami, Alissa L Nana, Quynh Nguyen, Peter J Kim, Joanna L Jankowsky, William W Seeley, Fenghua Hu

Faculty, Staff and Students Publications

TMEM106B, a lysosomal transmembrane protein, has been closely associated with brain health. Recently, an intriguing link between TMEM106B and brain inflammation has been discovered, but how TMEM106B regulates inflammation is unknown. Here, we report that TMEM106B deficiency in mice leads to reduced microglia proliferation and activation and increased microglial apoptosis in response to demyelination. We also found an increase in lysosomal pH and a decrease in lysosomal enzyme activities in TMEM106B-deficient microglia. Furthermore, TMEM106B loss results in a significant decrease in the protein levels of TREM2, an innate immune receptor essential for microglia survival and activation. Specific ablation of TMEM106B …

Social Deprivation Induces Astrocytic Trpa1-Gaba Suppression Of Hippocampal Circuits, Yi-Ting Cheng, Junsung Woo, Estefania Luna-Figueroa, Ehson Maleki, Akdes Serin Harmanci, Benjamin Deneen

Faculty, Staff and Students Publications

Social experience is essential for the development and maintenance of higher order brain function. Social deprivation results in a host of cognitive deficits and cellular studies have largely focused on associated neuronal dysregulation; how astrocyte function is impacted by social deprivation is unknown. Here we show that hippocampal astrocytes from juvenile mice subjected to social isolation exhibit increased Ca2+ activity and global changes in gene expression. We found that the Ca2+ channel TRPA1 is upregulated in astrocytes after social deprivation and astrocyte-specific deletion of TRPA1 reverses the physiological and cognitive deficits associated with social deprivation. Mechanistically, TRPA1 inhibition of hippocampal …

Wwox P47t Partial Loss-Of-Function Mutation Induces Epilepsy, Progressive Neuroinflammation, And Cerebellar Degeneration In Mice Phenocopying Human Scar12, Tabish Hussain, Kevin Sanchez, Jennifer Crayton, Dhurjhoti Saha, Collene Jeter, Yue Lu, Martin Abba, Ryan Seo, Jeffrey L Noebels, Laura Fonken, C Marcelo Aldaz

Faculty, Staff and Student Publications

WWOX gene loss-of-function (LoF) has been associated with neuropathologies resulting in developmental, epileptic, and ataxic phenotypes of varying severity based on the level of WWOX dysfunction. WWOX gene biallelic germline variant p.Pro47Thr (P47T) has been causally associated with a new form of autosomal recessive cerebellar ataxia with epilepsy and intellectual disability (SCAR12, MIM:614322). This mutation affecting the WW1 protein binding domain of WWOX, impairs its interaction with canonical proline-proline-X-tyrosine motifs in partner proteins. We generated a mutant knock-in mouse model of Wwox P47T mutation that phenocopies human SCAR12. Wwox

Single-Cell Rna Sequencing Reveals Immunosuppressive Myeloid Cell Diversity During Malignant Progression In A Murine Model Of Glioma, Sakthi Rajendran, Yang Hu, Alessandro Canella, Clayton Peterson, Amy Gross, Maren Cam, Matthew Nazzaro, Abigail Haffey, Akdes Serin-Harmanci, Rosario Distefano, Giovanni Nigita, Wesley Wang, Daniel Kreatsoulas, Zihai Li, Jesse A Sepeda, Andrew Sas, Mark E Hester, Katherine E Miller, Olivier Elemento, Ryan D Roberts, Eric C Holland, Ganesh Rao, Elaine R Mardis, Prajwal Rajappa

Faculty, Staff and Students Publications

Recent studies have shown the importance of the dynamic tumor microenvironment (TME) in high-grade gliomas (HGGs). In particular, myeloid cells are known to mediate immunosuppression in glioma; however, it is still unclear if myeloid cells play a role in low-grade glioma (LGG) malignant progression. Here, we investigate the cellular heterogeneity of the TME using single-cell RNA sequencing in a murine glioma model that recapitulates the malignant progression of LGG to HGG. LGGs show increased infiltrating CD4+ and CD8+ T cells and natural killer (NK) cells in the TME, whereas HGGs abrogate this infiltration. Our study identifies distinct macrophage clusters in …

Evolutionarily Conserved Regulators Of Tau Identify Targets For New Therapies, Jiyoen Kim, Maria De Haro, Ismael Al-Ramahi, Lorena Laura Garaicoechea, Hyun-Hwan Jeong, Jun Young Sonn, Bakhos Tadros, Zhandong Liu, Juan Botas, Huda Yahya Zoghbi

Duncan NRI Faculty and Staff Publications

Tauopathies are neurodegenerative diseases that involve the pathological accumulation of tau proteins; in this family are Alzheimer disease, corticobasal degeneration, and chronic traumatic encephalopathy, among others. Hypothesizing that reducing this accumulation could mitigate pathogenesis, we performed a cross-species genetic screen targeting 6,600 potentially druggable genes in human cells and Drosophila. We found and validated 83 hits in cells and further validated 11 hits in the mouse brain. Three of these hits (USP7, RNF130, and RNF149) converge on the C terminus of Hsc70-interacting protein (CHIP) to regulate tau levels, highlighting the role of CHIP in maintaining tau proteostasis in the brain. …

In Vivo Functional Characterization Of Egfr Variants Identifies Novel Drivers Of Glioblastoma, Kwanha Yu, Kathleen Kong, Brittney Lozzi, Estefania Luna-Figueroa, Alexis Cervantes, Rachel Curry, Carrie A Mohila, Ganesh Rao, Ali Jalali, Gordon B Mills, Kenneth L Scott, Benjamin Deneen

Faculty, Staff and Students Publications

BACKGROUND: Glioblastoma is the most common and aggressive primary brain tumor. Large-scale sequencing initiatives have cataloged its mutational landscape in hopes of elucidating mechanisms driving this deadly disease. However, a major bottleneck in harnessing this data for new therapies is deciphering "driver" and "passenger" events amongst the vast volume of information.

METHODS: We utilized an autochthonous, in vivo screening approach to identify driver, EGFR variants. RNA-Seq identified unique molecular signatures of mouse gliomas across these variants, which only differ by a single amino acid change. In particular, we identified alterations to lipid metabolism, which we further validated through an unbiased …

A Comprehensive And Integrative Approach To Mecp2 Disease Transcriptomics, Alexander J Trostle, Lucian Li, Seon-Young Kim, Jiasheng Wang, Rami Al-Ouran, Hari Krishna Yalamanchili, Zhandong Liu, Ying-Wooi Wan

Faculty, Staff and Students Publications

Mutations in MeCP2 result in a crippling neurological disease, but we lack a lucid picture of MeCP2's molecular role. Individual transcriptomic studies yield inconsistent differentially expressed genes. To overcome these issues, we demonstrate a methodology to analyze all modern public data. We obtained relevant raw public transcriptomic data from GEO and ENA, then homogeneously processed it (QC, alignment to reference, differential expression analysis). We present a web portal to interactively access the mouse data, and we discovered a commonly perturbed core set of genes that transcends the limitations of any individual study. We then found functionally distinct, consistently up- and …

New Mouse Models With Hypomorphic Sumf1 Variants Mimic Attenuated Forms Of Multiple Sulfatase Deficiency, Nicolina Cristina Sorrentino, Maximiliano Presa, Sergio Attanasio, Vincenzo Cacace, Martina Sofia, Aamir Zuberi, Jennifer Ryan, Somdatta Ray, Igor Petkovic, Karthikeyan Radhakrishnan, Lars Schlotawa, Andrea Ballabio, Cathleen Lutz, Nicola Brunetti-Pierri

Duncan NRI Faculty and Staff Publications

Multiple sulfatase deficiency (MSD) is an ultrarare lysosomal storage disorder due to deficiency of all known sulfatases. MSD is caused by mutations in the Sulfatase Modifying Factor 1 (SUMF1) gene encoding the enzyme responsible for the post-translational modification and activation of all sulfatases. Most MSD patients carry hypomorph SUMF1 variants resulting in variable degrees of residual sulfatase activities. In contrast, Sumf1 null mice with complete deficiency in all sulfatase enzyme activities, have very short lifespan with significant pre-wean lethality, owing to a challenging preclinical model. To overcome this limitation, we genetically engineered and characterized in mice two commonly …

Tfeb-Mediated Lysosomal Exocytosis Alleviates High-Fat Diet-Induced Lipotoxicity In The Kidney, Jun Nakamura, Takeshi Yamamoto, Yoshitsugu Takabatake, Tomoko Namba-Hamano, Satoshi Minami, Atsushi Takahashi, Jun Matsuda, Shinsuke Sakai, Hiroaki Yonishi, Shihomi Maeda, Sho Matsui, Isao Matsui, Takayuki Hamano, Masatomo Takahashi, Maiko Goto, Yoshihiro Izumi, Takeshi Bamba, Miwa Sasai, Masahiro Yamamoto, Taiji Matsusaka, Fumio Niimura, Motoko Yanagita, Shuhei Nakamura, Tamotsu Yoshimori, Andrea Ballabio, Yoshitaka Isaka

Duncan NRI Faculty and Staff Publications

Obesity is a major risk factor for end-stage kidney disease. We previously found that lysosomal dysfunction and impaired autophagic flux contribute to lipotoxicity in obesity-related kidney disease, in both humans and experimental animal models. However, the regulatory factors involved in countering renal lipotoxicity are largely unknown. Here, we found that palmitic acid strongly promoted dephosphorylation and nuclear translocation of transcription factor EB (TFEB) by inhibiting the mechanistic target of rapamycin kinase complex 1 pathway in a Rag GTPase-dependent manner, though these effects gradually diminished after extended treatment. We then investigated the role of TFEB in the pathogenesis of obesity-related kidney …

Cxcr4 Expression Is Associated With Proneural-To-Mesenchymal Transition In Glioblastoma, A Basit Khan, Sungho Lee, Akdes Serin Harmanci, Rajan Patel, Khatri Latha, Yuhui Yang, Anantha Marisetty, Hyun-Kyoung Lee, Amy B Heimberger, Gregory N Fuller, Benjamin Deneen, Ganesh Rao

Faculty, Staff and Students Publications

Glioblastoma (GBM) is the most common primary intracranial malignant tumor and consists of three molecular subtypes: proneural (PN), mesenchymal (MES) and classical (CL). Transition between PN to MES subtypes (PMT) is the glioma analog of the epithelial-mesenchymal transition (EMT) in carcinomas and is associated with resistance to therapy. CXCR4 signaling increases the expression of MES genes in glioma cell lines and promotes EMT in other cancers. RNA sequencing (RNAseq) data of PN GBMs in The Cancer Genome Atlas (TCGA) and secondary high-grade gliomas (HGGs) from an internal cohort were examined for correlation between CXCR4 expression and survival as well as …

Disruption Of The Atxn1-Cic Complex Reveals The Role Of Additional Nuclear Atxn1 Interactors In Spinocerebellar Ataxia Type 1, Stephanie L Coffin, Mark A Durham, Larissa Nitschke, Eder Xhako, Amanda M Brown, Jean-Pierre Revelli, Esmeralda Villavicencio Gonzalez, Tao Lin, Hillary P Handler, Yanwan Dai, Alexander J Trostle, Ying-Wooi Wan, Zhandong Liu, Roy V Sillitoe, Harry T Orr, Huda Y Zoghbi

Faculty, Staff and Students Publications

Spinocerebellar ataxia type 1 (SCA1) is a paradigmatic neurodegenerative disease in that it is caused by a mutation in a broadly expressed protein, ATXN1; however, only select populations of cells degenerate. The interaction of polyglutamine-expanded ATXN1 with the transcriptional repressor CIC drives cerebellar Purkinje cell pathogenesis; however, the importance of this interaction in other vulnerable cells remains unknown. Here, we mutated the 154Q knockin allele of Atxn1154Q/2Q mice to prevent the ATXN1-CIC interaction globally. This normalized genome-wide CIC binding; however, it only partially corrected transcriptional and behavioral phenotypes, suggesting the involvement of additional factors in disease pathogenesis. Using unbiased …