The N-terminal methyltransferase homologs NRMT1 and NRMT2 exhibit novel regulation of activity through heterotrimer formation.

Protein, DNA, and RNA methyltransferases have an ever-expanding list of novel substrates and catalytic activities. Even within families and between homologs, it is becoming clear the intricacies of methyltransferase specificity and regulation are far more diverse than originally thought. In addition to specific substrates and distinct methylation levels, methyltransferase activity can be altered through formation of complexes with close homologs. This work involves the N-terminal methyltransferase homologs NRMT1 and NRMT2. NRMT1 is a ubiquitously expressed distributive trimethylase. NRMT2 is a monomethylase expressed at low levels and in a tissue-specific manner. They are both nuclear methyltransferases with overlapping target consensus sequences but have distinct enzymatic activities and tissue expression patterns. Co-expression of NRMT1 with NRMT2 increases the trimethylation activity of NRMT1, and here I aim to understand how this occurs. I used analytical ultracentrifugation to show that while NRMT1 primarily exists as a dimer and NRMT2 as a monomer, when co-expressed they form a heterotrimer. I used co-immunoprecipitation and molecular modeling to demonstrate in vivo binding and map areas of interaction. While overexpression of NRMT2 increased the half-life of NRMT1, the reciprocal experiment did not produce the same results, indicating that NRMT2 may be increasing NRMT1 activity via increase the stability of the enzyme. Accordingly, the catalytic activity of NRMT2 is not needed to increase NRMT1 activity or increase its affinity for less preferred substrates. Additionally, monomethylation could not rescue phenotypes seen with loss of trimethylation. Taken together, these data support a model where NRMT2 expression activates NRMT1 activity, not through a catalytic change, but by increasing the stability and substrate affinity of NRMT1

Regulation of Endothelial Nitric Oxide Synthase in Pulmonary Myofibroblasts

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease leading to decreased lung volume and eventual respiratory failure. At present, the median post-diagnosis lifespan is between three and six years. Myofibroblasts are collagen-secreting cells essential for wound healing, but also implicated in the fibroproliferation and extra cellular matrix deposition commonly seen in IPF. The nitric oxide (NO) signaling pathway is implicated in protomyofibroblast to myofibroblast transition and regulation. Previous work has shown that in pulmonary myofibroblasts, endothelial nitric oxide synthase (eNOS) is the primary NOS isoform expressed. The current study used cultured rat pulmonary myofibroblasts between passages two and five as a cell model. The cells were grown in normal growth media (DMEM + 10% FBS) or serum starved (DMEM + 0% FBS) to induce cellular differentiation. In this study, immunocytochemistry was used to show localization of eNOS is dependent on cellular differentiation, with protomyofibroblasts expressing eNOS primarily in the nucleus and protomyofibroblasts expressing eNOS in the perinuclear region. We also show catalytic activity and localization of eNOS are correlated by visualizing nitric oxide production in the cells using a permeable fluorescein chromophore. By using western blot analysis on fractionated cell lysates we found eNOS expressed in the nucleus under normal growth conditions. eNOS is at least partially regulated by intracellular calcium (Ca2+) and calmodulin (CaM). Western blot analysis using native eNOS and phospho-specific eNOS antibodies on fractionated cells treated with the protein kinase C (PKC) activator phorbal 12-myristate 13-acetate (PMA) with and without addition of its antagonist ethylene glycol tetraacetic acid (EGTA) was conducted to investigate PKC’s role in eNOS regulation by phosphorylation. Indeed, PKC activation was found to mitigate expression in the nucleus, while inhibition of the activator restored the activity expression above basal levels. This finding correlates with previous data from our lab showing a decrease in activity in myofibroblasts treated with PMA and assayed amperometrically with an NO electrode

Annotated record of the detailed examination of Mn deposits from the NAGA Expedition stations

The observations described in this report were made during the NAGA Expedition, Phase 1 between San Diego and Honolulu in June 1959 by Scripps Institution of Oceanography from, the R/V Stanger. Cores, bottom photographs and dredges are available at Scripps for sampling and study

STUDY 1: Prenatal Effects of Cocaine on Japanese Quail

Recent trends of cocaine use have been reported in pregnant women across the United States. The National Pregnancy and Health Survey reported that more than 40,000 infants born each year are exposed to cocaine prenatally. Clinical studies have reported that exposure to cocaine in the womb may impair prenatal and postnatal brain growth, and adversely affect motor function, reactivity, language development, and attentional mechanisms. Despite unresolved questions about cocaine\u27s effects on early central nervous system development in humans, the literature with animal models continues to demonstrate a variety of neurobehavioral and neurodevelopmental abnormalities that result from prenatal cocaine exposure. This study investigated the effects of prenatal exposure of cocaine on Japanese quail embryos (N=160) and seeked to understand the adverse effects it has on embrotic development. The design of this experiment was and still is a longitudinal study aimed to investigate the effects of cocaine over the course of the Japanese quail\u27s life from birth to adulthood. This study will seek to understand cocaine\u27s implications on hatching, development, learning, and behavior. Research on prenatal exposure to cocaine is very important and prevalent in today\u27s modern society where drug abuse is on the rise. Japanese quail serve as the perfect model for studying prenatal effects of cocaine because of their short developmental rate into adulthood which is ideal when studying long-lasting effects of drugs. By studying avian species, we are able to get a better understanding of how prenatal cocaine affects development, learning, and behavior within a human model

Experiencia docente: los estudiantes se ponen sus gafas de color de mates con selfies matemáticos

As math teachers and teacher educators, we are always looking for new ways to make sure math is perceived as important by other people. Recently, we have been exploring the idea of visualizing mathematical concepts through photography: we invented the notion of mathematical selfies to take a look at how mathematics can be popularized and how global motivation for Engaging in math activities can be enhanced by using visual math embedded in a real context. Here we share an example of how mathematical selfies can lead to a path of greater mathematical awareness for everyone. So what is a mathematical selfie? Well, a «selfie» is commonly defined as a photographic self-portrait. We extend this definition to mathematical selfies as external representations of one's mathematical perception of the world, in other words, a self-portrait of your mathematical world. Successively, mathematical knowledge or mathematical consciousness are defined as the knowledge or perception of the presence of mathematics that surrounds us. We will classify the antonym as mathematical blindness, a severe and pervasive state that allows people to go about their daily lives without realizing the sheer amount of mathematics around them.Como profesores de matemáticas y formadores de profesores, siempre buscamos nuevas formas de asegurarnos de que las matemáticas sean percibidas como importantes por otras personas. Recientemente, hemos estado explorando la idea de visualizar conceptos matemáticos a través de la fotografía: inventamos la noción de selfies matemáticos para echar un vistazo a cómo las matemáticas pueden ser popularizadas y cómo la motivación global por involucrarse en actividades matemáticas puede incrementarse al usar matemáticas visuales incrustadas en un contexto real. Aquí compartimos un ejemplo de cómo los selfies matemáticos pueden llevar a una senda de mayor concienciación matemática para todos. Así que, ¿qué es un selfie matemático? Pues bien, un «selfie» es comúnmente definido como un autorretrato fotográfico. Nosotros ampliamos esta definición a los selfies matemáticos como representaciones externas de la propia percepción matemática del mundo, en otras palabras, un autorretrato de tu mundo matemático. Sucesivamente, el conocimiento matemático o conciencia matemática son definidos como el conocimiento o la percepción de la presencia de las matemáticas que nos rodea. Clasificaremos el antónimo como ceguera matemática, un estado severo y generalizado que permite a las personas ocuparse de sus vidas diarias sin darse cuenta alguna de la gran cantidad de matemáticas que les rodean

Social and Physical Cognition in Chimpanzees (Pan troglodytes ): Preliminary Investigation of Domain-General versus Domain-Specific Intelligence

Comparative and evolutionary cognitive scientists disagree on whether human and nonhuman primate cognition is driven by a general intelligence or more specific, modular mechanisms. Comparative research with chimpanzees is extensive and provides the opportunity to better understand the evolution of human cognition. Little research has been dedicated to individual differences in chimpanzee social and physical cognition. The study of individual differences can be informative in better understanding the generality of primate intelligence. Results supporting a correlation between performances in the social and physical domains would suggest that a domain-general inference system may be responsible. If no relationship is revealed between performances then more compartmentalized, modular mechanisms may be responsible. As a preliminary investigation, I administered four studies focusing on social and physical cognition to a large number of captive chimpanzees. Performance on two tool-using tasks served as indicators of physical intelligence. I administered two social investigations regarding individual variation in social responsiveness and sociability. I did not find a correlation between the social and physical investigations; however strong individual differences in performances were observed. Demographic factors sometimes played a role in the results presented here (e.g. dominance rank and age). While this research does not demonstrate a relationship between sociability and physical intelligence, additional social measures should be utilized in order to measure social cognitive ability in chimpanzees. Focusing on individual differences with a battery of social and physical tasks will be informative regarding the structure of primate intelligence and the underlying cognitive mechanisms that are responsible

Final Report of Naga Expedition

SIO Reference 63-1