Medicine and Health Sciences Commons^™

Dysregulation Of The Mitogen Granulin In Human Cancer Through The Mir-15/107 Microrna Gene Group, Wang-Xia Wang, Natasha Kyprianou, Xiaowei Wang, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

Granulin (GRN) is a potent mitogen and growth factor implicated in many human cancers, but its regulation is poorly understood. Recent findings indicate that GRN is regulated strongly by the microRNA miR-107, which functionally overlaps with miR-15, miR-16, and miR-195 due to a common 5′ sequence critical for target specificity. In this study, we queried whether miR-107 and paralogs regulated GRN in human cancers. In cultured cells, anti-argonaute RNA coimmunoprecipitation with downstream microarray analyses indicates that GRN mRNA is directly targeted by numerous miR-15/107 miRNAs. We further tested this association in human tumors. MiR-15 and miR-16 are known to be …

The Mir-15/107 Group Of Microrna Genes: Evolutionary Biology, Cellular Functions, And Roles In Human Diseases, John R. Finnerty, Wang-Xia Wang, Sébastien S. Hébert, Bernard R. Wilfred, Guogen Mao, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

The miR-15/107 group of microRNA (miRNA) gene is increasingly appreciated to serve key functions in humans. These miRNAs regulate gene expression involved in cell division, metabolism, stress response, and angiogenesis in vertebrate species. The miR-15/107 group has also been implicated in human cancers, cardiovascular disease and neurodegenerative disease, including Alzheimer's disease. Here we provide an overview of the following: (1) the evolution of miR-15/107 group member genes; (2) the expression levels of miRNAs in mammalian tissues; (3) evidence for overlapping gene-regulatory functions by different miRNAs; (4) the normal biochemical pathways regulated by miR-15/107 group miRNAs; and (5) the roles played …

Microrna-21 Dysregulates The Expression Of Mef2c In Neurons In Monkey And Human Siv/Hiv Neurological Disease., Sowmya V. Yelamanchili, A Datta Chaudhuri, L N. Chen, Huangui Xiong, Howard S. Fox

Journal Articles: Pharmacology & Experimental Neuroscience

MicroRNAs (miRNAs) play important roles in regulating a plethora of physiological and pathophysiogical processes including neurodegeneration. In both HIV associated dementia in humans and its monkey model SIV encephalitis we find miR-21, a miRNA largely known for its link to oncogenesis, to be significantly upregulated in the brain. In situ hybridization of the diseased brain sections revealed induction of miR-21 in neurons. MiR-21 can be induced in neurons by prolonged N-methyl-D-aspartic acid receptor stimulation, an excitotoxic process active in HIV and other neurodegenerative diseases. Introduction of miR-21 into human neurons leads to pathological functional defects. Furthermore, we show that miR-21 …

Multiple Mechanisms Of Consciousness: The Neural Correlates Of Emotional Awareness., Jayna M Amting, Steven G Greening, Derek G V Mitchell

Brain and Mind Institute Researchers' Publications

Emotional stimuli, including facial expressions, are thought to gain rapid and privileged access to processing resources in the brain. Despite this access, we are conscious of only a fraction of the myriad of emotion-related cues we face everyday. It remains unclear, therefore, what the relationship is between activity in neural regions associated with emotional representation and the phenomenological experience of emotional awareness. We used functional magnetic resonance imaging and binocular rivalry to delineate the neural correlates of awareness of conflicting emotional expressions in humans. Behaviorally, fearful faces were significantly more likely to be perceived than disgusted or neutral faces. Functionally, …

Deficits In Attention To Emotional Stimuli Distinguish Youth With Severe Mood Dysregulation From Youth With Bipolar Disorder., Brendan A Rich, Melissa A Brotman, Daniel P Dickstein, Derek G V Mitchell, R James R Blair, Ellen Leibenluft

Brain and Mind Institute Researchers' Publications

Studying attention in the context of emotional stimuli may aid in differentiating pediatric bipolar disorder (BD) from severe mood dysregulation (SMD). SMD is characterized by chronic irritability, arousal, and hyper-reactivity; SMD youth frequently receive a BD diagnosis although they do not meet DSM-IV criteria for BD because they lack manic episodes. We compared 57 BD (14.4 +/- 2.9 years old, 56% male), 41 SMD (12.6 +/- 2.6 years old, 66% male), and 33 control subjects (13.7 +/- 2.5 years old, 52% male) using the Emotional Interrupt task, which examines how attention is impacted by positive, negative, or neutral distracters. We …

High-Throughput Experimental Studies To Identify Mirna Targets Directly, With Special Focus On The Mammalian Brain, Peter T. Nelson, Marianthi Kiriakidou, Zissimos Mourelatos, Grace S. Tan, Mary H. Jennings, Kevin Xie, Wang-Xia Wang

Pathology and Laboratory Medicine Faculty Publications

We review the pertinent literature on methods used in high-throughput experimental identification of microRNA (miRNA) "targets" with emphasis on neurochemical studies. miRNAs are short regulatory noncoding RNAs that play important roles in the mammalian brain. The functions of miRNAs are related to their binding of RNAs including mRNAs. Since mammalian miRNAs tend to bind to target mRNAs via imperfect complementarity, understanding exactly which target mRNAs are recognized by which specific miRNAs is a challenge. Based on early experimental evidence, a set of "binding rules" for miRNAs has been described. These have focused on the 5' "seed" region of miRNAs binding …

Individual Micrornas (Mirnas) Display Distinct Mrna Targeting "Rules", Wang-Xia Wang, Bernard R. Wilfred, Kevin Xie, Mary H. Jennings, Yanling Hu, Arnold J. Stromberg, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

MicroRNAs (miRNAs) guide Argonaute (AGO)-containing microribonucleoprotein (miRNP) complexes to target mRNAs.It has been assumed that miRNAs behave similarly to each other with regard to mRNA target recognition. The usual assumptions, which are based on prior studies, are that miRNAs target preferentially sequences in the 3'UTR of mRNAs,guided by the 5' "seed" portion of the miRNAs. Here we isolated AGO- and miRNA-containing miRNPs from human H4 tumor cells by co-immunoprecipitation (co-IP) with anti-AGO antibody. Cells were transfected with miR-107, miR-124,miR-128, miR-320, or a negative control miRNA. Co-IPed RNAs were subjected to downstream high-density Affymetrix Human Gene 1.0 ST microarray analyses using …

Bold Signal In Both Ipsilateral And Contralateral Retinotopic Cortex Modulates With Perceptual Fading, Po-Jang Hsieh, Peter U. Tse

Dartmouth Scholarship

Under conditions of visual fixation, perceptual fading occurs when a stationary object, though present in the world and continually casting light upon the retina, vanishes from visual consciousness. The neural correlates of the consciousness of such an object will presumably modulate in activity with the onset and cessation of perceptual fading.

Method: In order to localize the neural correlates of perceptual fading, a green disk that had been individually set to be equiluminant with the orange background, was presented in one of the four visual quadrants; Subjects indicated with a button press whether or not the disk was subjectively visible …

Anti-Argonaute Rip-Chip Shows That Mirna Transfections Alter Global Patterns Of Mrna Recruitment To Microribonucleoprotein Complexes, Wang-Xia Wang, Bernard R. Wilfred, Yanling Hu, Arnold J. Stromberg, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

MicroRNAs (miRNAs) play key roles in gene expression regulation by guiding Argonaute (AGO)-containing microribonucleoprotein (miRNP) effector complexes to target polynucleotides. There are still uncertainties about how miRNAs interact with mRNAs. Here we employed a biochemical approach to isolate AGO-containing miRNPs from human H4 tumor cells by co-immunoprecipitation (co-IP) with a previously described anti-AGO antibody. Co-immunoprecipitated (co-IPed) RNAs were subjected to downstream Affymetrix Human Gene 1.0 ST microarray analysis. During rigorous validation, the "RIP-Chip" assay identified target mRNAs specifically associated with AGO complexes. RIP-Chip was performed after transfecting brain-enriched miRNAs (miR-107, miR-124, miR-128, and miR-320) and nonphysiologic control miRNA to identify …

Mir-107 Is Reduced In Alzheimer's Disease Brain Neocortex: Validation Study, Peter T. Nelson, Wang-Xia Wang

Pathology and Laboratory Medicine Faculty Publications

MiR-107 is a microRNA (miRNA) that we reported previously to have decreased expression in the temporal cortical gray matter early in the progression of Alzheimer's disease (AD). Here we study a new group of well-characterized human temporal cortex samples (N=19). MiR-107 expression was assessed, normalized to miR-124 and let-7a. Correlation was observed between decreased miR-107 expression and increased neuritic plaque counts (P< 0.05) and neurofibrillary tangle counts (P< 0.02) in adjacent brain tissue. Adjusted miR-107 and BACE1 mRNA levels tended to correlate negatively (trend with regression P< 0.07). In sum, miR-107 expression tends to be lower relative to other miRNAs as AD progresses.