Oral Session : Increasing Expectations in Adapted Athletics and Paralympic Sports

( Brent Hardin ) 한국체육학회 2013 In Pursuit of Evidence-Based Sport and Exercise Sc Vol.0 No.-

You Can’t (Re)make a Mother

Michael Hardin(마이클 하딘) 동국대학교 영상미디어센터 2012 씨네포럼 Vol.0 No.14

몇몇은 SF 영화 텍스트에서, 생명을 생성하는 욕망의 기제로 메리셸리의 『프랑켄슈타인』을 사용하고 있는데, 이러한 텍스트는 종종 생명을 만드는 여성의 능력에 대한 남성들의 욕망의 은유로 읽혀지고 있다. 이처럼 불안은 현대 사회의 생명탄생에 있어서 남성의 역할을 무마시키는 복제기술에 대한 논쟁으로 거듭 확대되고 있다. 영화 〈신체강탈자의 침입〉(1956/1978)과 〈화성에서 온 침입자〉(1953/ 1986)와 같은 텍스트들은 점점 비인간적으로 되어가는 인간의 모습으로 어머니의 역할에 초점을 두고 있다. 이들 영화의 두 원작은 냉전에 대한 알레고리로 읽혀지고 있지만, 모성상실에 기인한 내재적 평온에 대한 즉각적인 위협으로 바라볼 수도 있다. 이러한 맥락에서 살펴보았을때, 이들 네 편의 영화는 특히 재생산, 교육, 및 고용 측면에서, 미국여성의 역할 변화에 대한 공격으로 바라볼 수 있다. In some science-fiction texts, Mary Shelley’s Frankenstein, for example, a desire to generate life drives the narrative; thus, these texts are often read as a metaphor for the male’s desire to appropriate the female’s ability to create life (this anxiety seems greatest in the contemporary debate over cloning, which could remove the male’s role entirely). Other texts, such as Invasion of the Body Snatchers (1956 and 1978) and Invaders from Mars (1953 and 1986), focus instead on the role of the mother as an increasingly inhuman (cold, distant) figure. Although the original versions of both films are read as lightly veiled allegories about the Cold War, one cannot separate the more immediate threat to domestic tranquility expressed in both films and their remakes: the loss of the role of Mother. When viewed in context, all four films become scathing attacks on the shifting role of women in the United States, specifically in terms of reproduction, education, and employment.

효소전처리가 면직물의 면씨껍질 제거에 미치는 영향

김주혜,김성훈,Ian R. Hardin 한국섬유공학회 2002 한국섬유공학회지 Vol.39 No.3

In a previous experiment, pectin was the binding material between the cotton fibers and the seed coat. Based on the results, several enzymes were chosen to treat cotton fabrics in order to investigate the effect of enzymatic treatment on seed coat fragment removal from the cotton fabrics. This experiment indicated that the enzymes used did not remove the seed coat fragments from the fabric by themselves. However, seed coat fragment removal and fabric whiteness improved with specific enzymatic pre-treatments followed by bleaching compared to bleaching only. Among the enzymes, one of the amylase showed the must enhancement in seed coat fragment removal. The effect of the artylase pre-treatment on the fabric whiteness and the seed coat fragment removal was as large as conventional alkaline scouring.

면씨 껍질의 물리적 구조와 화학적 조성

김주혜,김성훈,Ian R. Hardin 한국섬유공학회 2001 한국섬유공학회지 Vol.38 No.12

The physical structure and chemical composition of the cotton-seed were examined with special interest focused on the attachment of cotton fibers to the seed coat. Hand-cut cross sections of the seed coat showed six layers distinctively: outer epidermis, outer pigment, color-less, palisade, inner pigment, and inner epidermis layer. The structure between the fibers and the seed coat was studied using optical microscopes and a scanning electron microscope. The fibers were located between outer epidermis cells and the roots of the fibers were attached to the surface of the outer pigment layer. Microtomed thin sections were used to identify chemical compositions of the layers. A series of stains was chosen to identify the chemical components such as lignin, tannin, lipid, and pectin in the seed coat. Ruthenium Red, which stains pectin, was of particular interest because the Ruthenium Red stained between the outer epidermis and the fiber shank. The results suggest that pectin is the material bonding fibers to the seed coat.

Repetitive Availability Demonstration Testing Procedure

Usher, J. S.,Aslam, M.,Hardin, C. T.,Jun, C.-H. ASTM AMERICAN SOCIETY FOR TESTING AND 2017 Journal of testing and evaluation Vol.45 No.3

A Conserved Phosphorylation Switch Controls the Interaction between Cadherin and β-Catenin In Vitro and In Vivo

Choi, H.J.,Loveless, T.,Lynch, A.M.,Bang, I.,Hardin, J.,Weis, William I. Cell Press 2015 DEVELOPMENTAL CELL Vol.33 No.1

<P>In metazoan adherens junctions, beta-catenin links the cytoplasmic tail of classical cadherins to the F-actin-binding protein a-catenin. Phosphorylation of a Ser/Thr-rich region in the cadherin tail dramatically enhances affinity for beta-catenin and promotes cell-cell adhesion in cell culture systems, but its importance has not been demonstrated in vivo. Here, we identify a critical phosphorylated serine in the C. elegans cadherin HMR-1 required for strong binding to the beta-catenin homolog HMP-2. Ablation of this phosphoserine interaction produces developmental defects that resemble full loss-of-function ( Hammerhead and Humpback) phenotypes. Most metazoans possess a single gene for beta-catenin, which is also a transcriptional coactivator in Wnt signaling. Nematodes and planaria, however, have a set of paralogous beta-catenins; for example, C. elegans HMP-2 functions only in cell-cell adhesion, whereas SYS-1 mediates transcriptional activation through interactions with POP-1/Tcf. Our structural data define critical sequence differences responsible for the unique ligand specificities of these two proteins.</P>

Cell–cell adhesion in metazoans relies on evolutionarily conserved features of the α-catenin·β-catenin–binding interface

Shao, Xiangqiang,Kang, Hyunook,Loveless, Timothy,Lee, Gyu Rie,Seok, Chaok,Weis, William I.,Choi, Hee-Jung,Hardin, Jeff American Society for Biochemistry and Molecular Bi 2017 The Journal of biological chemistry Vol.292 No.40

<P>Stable tissue integrity during embryonic development relies on the function of the cadherin center dot catenin complex (CCC). The Caenorhabditis elegans CCC is a useful paradigm for analyzing in vivo requirements for specific interactions among the core components of the CCC, and it provides a unique opportunity to examine evolutionarily conserved mechanisms that govern the interaction between alpha- and beta-catenin. HMP-1, unlike its mammalian homolog alpha-catenin, is constitutively monomeric, and its binding affinity for HMP-2/beta-catenin is higher than that of alpha-catenin for beta-catenin. A crystal structure shows that the HMP-1 center dot HMP-2 complex forms a five-helical bundle structure distinct from the structure of the mammalian alpha-catenin beta-catenin complex. Deletion analysis based on the crystal structure shows that the first helix of HMP-1 is necessary for binding HMP-2 avidly in vitro and for efficient recruitment of HMP-1 to adherens junctions in embryos. HMP-2 Ser-47 and Tyr-69 flank its binding interface with HMP-1, and we show that phosphomimetic mutations at these two sites decrease binding affinity of HMP-1 to HMP-2 by 40-100-fold in vitro. In vivo experiments using HMP-2 S47E and Y69E mutants showed that they are unable to rescue hmp-2(zu364) mutants, suggesting that phosphorylation of HMP-2 on Ser-47 and Tyr-69 could be important for regulating CCC formation in C. elegans. Our data provide novel insights into how cadherin-dependent cell-cell adhesion is modulated in metazoans by conserved elements as well as features unique to specific organisms.</P>

Structural and functional characterization of <i>Caenorhabditis elegans</i> α-catenin reveals constitutive binding to β-catenin and F-actin

Kang, Hyunook,Bang, Injin,Jin, Kyeong Sik,Lee, Boyun,Lee, Junho,Shao, Xiangqiang,Heier, Jonathon A.,Kwiatkowski, Adam V.,Nelson, W. James,Hardin, Jeff,Weis, William I.,Choi, Hee-Jung American Society for Biochemistry and Molecular Bi 2017 The Journal of biological chemistry Vol.292 No.17

<P>Intercellular epithelial junctions formed by classical cadherins, beta-catenin, and the actin-binding protein alpha-catenin link the actin cytoskeletons of adjacent cells into a structural continuum. These assemblies transmit forces through the tissue and respond to intracellular and extracellular signals. However, the mechanisms of junctional assembly and regulation are poorly understood. Studies of cadherin-catenin assembly in a number of metazoans have revealed both similarities and unexpected differences in the biochemical properties of the cadherin center dot catenin complex that likely reflect the developmental and environmental requirements of different tissues and organisms. Here, we report the structural and biochemical characterization of HMP-1, the Caenorhabditis elegans alpha-catenin homolog, and compare it with mammalian alpha-catenin. HMP-1 shares overall similarity in structure and actin-binding properties, but displayed differences in conformational flexibility and allosteric regulation from mammalian alpha-catenin. HMP-1 bound filamentous actin with an affinity in the single micromolar range, even when complexed with the beta-catenin homolog HMP-2 or when present in a complex of HMP-2 and the cadherin homolog HMR-1, indicating that HMP-1 binding to F-actin is not allosterically regulated by the HMP-2.HMR-1 complex. The middle (i.e. M) domain of HMP-1 appeared to be less conformationally flexible than mammalian alpha-catenin, which may underlie the dampened effect of HMP-2 binding on HMP-1 actin-binding activity compared with that of the mammalian homolog. In conclusion, our data indicate that HMP-1 constitutively binds beta-catenin and F-actin, and although the overall structure and function of HMP-1 and related alpha-catenins are similar, the vertebrate proteins appear to be under more complex conformational regulation.</P>

Phosphorylation of a Central Clock Transcription Factor Is Required for Thermal but Not Photic Entrainment

Lee, Euna,Jeong, Eun Hee,Jeong, Hyun-Jeong,Yildirim, Evrim,Vanselow, Jens T.,Ng, Fanny,Liu, Yixiao,Mahesh, Guruswamy,Kramer, Achim,Hardin, Paul E.,Edery, Isaac,Kim, Eun Young Public Library of Science 2014 PLoS genetics Vol.10 No.8

<▼1><P>Transcriptional/translational feedback loops drive daily cycles of expression in clock genes and clock-controlled genes, which ultimately underlie many of the overt circadian rhythms manifested by organisms. Moreover, phosphorylation of clock proteins plays crucial roles in the temporal regulation of clock protein activity, stability and subcellular localization. dCLOCK (dCLK), the master transcription factor driving cyclical gene expression and the rate-limiting component in the <I>Drosophila</I> circadian clock, undergoes daily changes in phosphorylation. However, the physiological role of dCLK phosphorylation is not clear. Using a <I>Drosophila</I> tissue culture system, we identified multiple phosphorylation sites on dCLK. Expression of a mutated version of dCLK where all the mapped phospho-sites were switched to alanine (dCLK-15A) rescues the arrythmicity of <I>Clk</I><SUP>out</SUP> flies, yet with an approximately 1.5 hr shorter period. The dCLK-15A protein attains substantially higher levels in flies compared to the control situation, and also appears to have enhanced transcriptional activity, consistent with the observed higher peak values and amplitudes in the mRNA rhythms of several core clock genes. Surprisingly, the clock-controlled daily activity rhythm in dCLK-15A expressing flies does not synchronize properly to daily temperature cycles, although there is no defect in aligning to light/dark cycles. Our findings suggest a novel role for clock protein phosphorylation in governing the relative strengths of entraining modalities by adjusting the dynamics of circadian gene expression.</P></▼1><▼2><P><B>Author Summary</B></P><P>Circadian clocks are synchronized to local time by daily cycles in light-dark and temperature. Although light is generally thought to be the most dominant entraining cue in nature, daily cycles in temperature are sufficient to synchronize clocks in a large range of organisms. In <I>Drosophila</I>, dCLOCK is a master circadian transcription factor that drives cyclical gene expression and is likely the rate-limiting component in the transcriptional/translational feedback loops that underlie the timekeeping mechanism. dCLOCK undergoes temporal changes in phosphorylation throughout a day, which is also observed for mammalian CLOCK. However, the role of CLOCK phosphorylation at the organismal level is still unclear. Using mass-spectrometry, we identified more than a dozen phosphorylation sites on dCLOCK. Blocking global phosphorylation of dCLOCK by mutating phospho-acceptor sites to alanine increases its abundance and transcriptional activity, leading to higher peak values and amplitudes in the mRNA rhythms of core clock genes, which likely explains the accelerated clock speed. Surprisingly, the clock-controlled daily activity rhythm fails to maintain synchrony with daily temperature cycles, although there is no observable defect in aligning to light/dark cycles. Our findings suggest a novel role for clock protein phosphorylation in governing the effective strengths of entraining modalities by adjusting clock amplitude.</P></▼2>

Phosphorylation of the Transcription Activator CLOCK Regulates Progression through a ∼24-h Feedback Loop to Influence the Circadian Period in <i>Drosophila</i>

Mahesh, Guruswamy,Jeong, EunHee,Ng, Fanny S.,Liu, Yixiao,Gunawardhana, Kushan,Houl, Jerry H.,Yildirim, Evrim,Amunugama, Ravi,Jones, Richard,Allen, David L.,Edery, Isaac,Kim, Eun Young,Hardin, Paul E. American Society for Biochemistry and Molecular Bi 2014 The Journal of biological chemistry Vol.289 No.28

<P>Circadian (≅24 h) clocks control daily rhythms in metabolism, physiology, and behavior in animals, plants, and microbes. In <I>Drosophila</I>, these clocks keep circadian time via transcriptional feedback loops in which CLOCK-CYCLE (CLK-CYC) initiates transcription of <I>period</I> (<I>per</I>) and <I>timeless</I> (<I>tim</I>), accumulating levels of PER and TIM proteins feed back to inhibit CLK-CYC, and degradation of PER and TIM allows CLK-CYC to initiate the next cycle of transcription. The timing of key events in this feedback loop are controlled by, or coincide with, rhythms in PER and CLK phosphorylation, where PER and CLK phosphorylation is high during transcriptional repression. PER phosphorylation at specific sites controls its subcellular localization, activity, and stability, but comparatively little is known about the identity and function of CLK phosphorylation sites. Here we identify eight CLK phosphorylation sites via mass spectrometry and determine how phosphorylation at these sites impacts behavioral and molecular rhythms by transgenic rescue of a new <I>Clk</I> null mutant. Eliminating phosphorylation at four of these sites accelerates the feedback loop to shorten the circadian period, whereas loss of CLK phosphorylation at serine 859 increases CLK activity, thereby increasing PER levels and accelerating transcriptional repression. These results demonstrate that CLK phosphorylation influences the circadian period by regulating CLK activity and progression through the feedback loop.</P>