11:10-12:00, Rm 103

NeuroscienceH-17-12Inhibition of dopaminergic neuron damage in Parkinson’s diseaseanimal model by PEP-1-Hsp27 proteinHye Won Kang, Min Jea Shin, Young Nam Kim, Su Jung Woo, Hyo Sang Jo, JaeJin An, Moo Ho Won¹, Sung-Woo Cho², Kyu Hyung Han, Jinseu Park, Dae WonKim, Won Sik Eum, Soo Young ChoiDepartment of Biomedical Science and Research Institute of Bioscience and Biotechnology, HallymUniversity, Chunchon 200-702, Korea, ¹Department of Neurobiology, School of Medicine,Kangwon National University, Chunchon 200-701, Korea, ²Department of Biochemistry andMolecular Biology, University of Ulsan College of Medicine, Seoul 138-736, KoreaParkinson’s disease (PD) is a common neurodegenerative disorder characterized by theprogressive loss of dopaminergic neurons in the substantia nigra (SN). However, themechanism of the pathology of PD still remains poorly understood. Heat shock protein 27(Hsp27) have very important functions, such as intracellular chaperones for otherproteins. Also, it has a potent ability to increase cell survival in response to oxidativestress. In this study, we have investigated the protective effects of PEP-1-Hsp27 againstdopaminergic neuronal damage. When PEP-1-Hsp27 protein was added to the culturemedium of dopaminergic neuronal cells, it rapidly entered the cells and protected themagainst cell death induced by oxidative stress. Immunohistochemical analysis revealedthat, when PEP-1-Hsp27 protein was intraperitoneally injected into C57BL/6J mouse, itprevented neuronal cell death in the substantia nigra (SN). Our results demonstrate thattransduced PEP-1-Hsp27 protects against cell death in vitro and in vivo, and suggest thatit provides a potential strategy for therapeutic delivery in various human diseases relatedROS including PD.H-17-15Morphological clues to growth and aggregation of brain sand in humanpineal glandJinkyung Kim, Hyun-Wook Kim, Soeun Chang, Jeewoong Kim, Imjoo Rhyu andJung Ho JeX-ray Imaging Center, School of Interdisciplinary Bioscience and Bioengineering, PohangUniversity of Science and Technology (POSTECH), Pohang, KoreaBrain sand (BS) is physiological consequences of calcification process usually found inpineal gland (PG). The BSs are known to grow with age, impact functions and diseasesof PG. However, little is known about detailed mechanisms in growth of BSs. To directlyvisualize 3-dimensonal (3-D) morphological features of the BS, we adopt synchrotron X-ray imaging system which can deliver micro-architecture of an entire human PG withoutphysical sectioning. The quantitative analysis of the BS size showed that the size inperiphery is much smaller than that in center. The BS size distribution of the center ispartially deviated from normal distribution comparing to that of the periphery, indicatingdifferent growth patterns of BS in different regions. The detailed internal structures of theBSs in 3-D geometry reveal that the concentric ring structure varies with the BS size.Larger BS has rough outer rings enveloping smooth inner rings while smaller one hasonly smooth rings, indicating the growth process for a single BS: the outer rings becomerough as the BS grows up. Interestingly, we found ‘integrated laminae’which surroundthe aggregation. This study provides accurate, 3-D description of BS structures, givingmorphological clues to growth and aggregation mechanisms of BS in human.H-17-13PEP-1-rpS3 transduction ameliorates neuronal cell injury in vitro and invivoEun Hee Ahn, Mi Jin Kim, Young Nam Kim, So Mi Kim, Tae-Cheon Kang¹, Duk-SooKim², Oh-Shin Kwon³, Joon Kim⁴, Kyu Hyung Han, Jinseu Park, Dae Won Kim,Won Sik Eum, Soo Young ChoiDepartment of Biomedical Science and Research Institute of Bioscience and Biotechnology, HallymUniversity, Chunchon 200-702, Korea, ¹Department of Anatomy and Neurobiology, College ofMedicine, Hallym University, Chunchon 200-702, Korea, ²Department of Anatomy, College ofMedicine, Soonchunhyang University, Cheonan-Si 330-090, Korea, ³Department of Biochemistry,Kyungpook National University, Taegu 702-701, Korea, ⁴School of Life Science and Biotechnology,Korea University, Seoul 136-701, KoreaRibosomal protein S3 (rpS3) is a component of 40S ribosomal subunit, known as UVendounclease and have apoptotic functions. Parkinson’s disease (PD) is well known acommon neurodegenerative disorder. In this study, we investigated the preventive effectof PEP-1-rpS3 on oxidative stress and 1-methyl-4-phenylpyridinium ion (MPP+)-inducedneuronal cell death. PEP-1-rpS3 efficiently transduced into SH-SY5Y cells in a time- anddose-dependent manner. PEP-1-rpS3 significantly inhibits H2O2 and the MPP+-inducedneurotoxicity of SH-SY5Y cells. PEP-1-rpS3 inhibits against intracellular ROS levels andDNA fragmentation. In addition, immunohistochemical analysis revealed that transducedPEP-1-rpS3 prevented neuronal cell death in the substantia nigra (SN) against 1-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP)-induced PD mouse models. In conclusion,PEP-1-rpS3 may be use therapeutic tools to reduce ROS related neurodegenerativediseases including PD.H-17-16Role of regulatory B subunits of protein phosphatase 2A (PP2A) inAlzheimer’s diseaseUn Young Yu and Jung-Hyuck AhnDepartment of Biochemistry, Ewha Womans University School of Medicine, Seoul 158-710, KoreaIn Alzheimer’s disease(AD) with hyperphosphorylated tau, it is known that the activityand expression of PP2A, a serine/threonine phosphatase, are decreased. Our previousstudy with transcriptome sequencing technique showed that expressions of catalyticsubunit as well as several regulatory subunits of protein phosphatase 2A were altered inAPP-swe mutant(K595N/M596L) expressing H4 cells(H4-swe) compared to H4 wild-typecells(H4-wt). Hyperphosphorylaed tau is important in pathogenesis of tauopathy includingAD, and several phosphorylation sites of tau is directly contribute to aggregation intoNFT. These sites are regulated by the activity of PP2A with specific B subunits. We foundthat tau was hyperphosphorylated in APP-swe compared to H4-wt at severalphosphorylated sites such as Ser262 and Ser422. To investigate which B subunit directlyact on these sites, we are studying how tau phosphorylation is changed with siRNAsagainst several B subunits expressed in H4-swe cells, including PPP2R5D, PPP2R5B,PPP2R2A, and PPP2R5E. We found that PP2A activity was necessary in the regulationof several phosphorylation sites, and actual B regulatory subunits that play a critical rolein this process were determined.H-17-14Tat-SAG protection on oxidative stress-induced neuronal cell injuryEun Jeong Sohn, Eun Hee Ahn, Soon Won Kwon, So Mi Kim, Hyo Sang Jo, Jae JinAn, Tae-Cheon Kang¹, Duk-Soo Kim², Oh-Shin Kwon³, Sung-Woo Cho⁴, JinseuPark, Dae Won Kim, Won Sik Eum, Soo Young ChoiDepartment of Biomedical Science and Research Institute of Bioscience and Biotechnology, HallymUniversity, Chunchon 200-702, Korea, ¹Department of Anatomy and Neurobiology, College ofMedicine, Hallym University, Chunchon 200-702, Korea, ²Department of Anatomy, College ofMedicine, Soonchunhyang University, Cheonan-Si 330-090, Korea, ³Department of Biochemistry,Kyungpook National University, Taegu 702-701, Korea, ⁴Department of Biochemistry andMolecular Biology, University of Ulsan College of Medicine, Seoul 138-736, KoreaThe pathological hallmark of Parkinson’s disease (PD) is dopaminergic cell death in thesubstantia nigra (SN), however the cause of cell death is unknown yet. Sensitive toapoptosis gene (SAG), a novel zinc RING finger protein, exhibits anti-apoptotic andantioxidant activity against a variety of redox reagent. In the present study, we examinedwhether Tat-SAG protein has protective effect against neurotoxicity. Tat-SAG protein wasadded to the culture medium for transduction at the human neuroblastoma SH-SY5Y cell.It was efficiently transduced into the cells and persisted into the cell until 48 hr.Transduced Tat-SAG protein protected cell viability and inhibited the generation of ROSlevel as well as DNA fragmentation against neurotoxicity. In the PD animal mousemodels, Tat-SAG protein protected against dopaminergic neuronal cell death in the SNregion. These results suggest that Tat-SAG protein provides tools for therapeutic deliveryagents in PD.H-17-17Amyloid β-induced FOXRED2 mediates neuronal cell death viainhibition of proteasome activitySangMi Shim, WonJae Lee, HaeWon Chung and Yong-Keun JungSchool of Biological Science, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, KoreaProteasome inhibition has been regarded as one of the mediators of Aβneurotoxicity. Inthis study, we found that FOXRED2, a novel ER-residential protein, is highly up-regulatedby Aβin rat cortical neurons and SH-SY5Y cells. Over-expression of FOXRED2 inhibitsproteasome activity in microsomal fractions containing ER and interferes with proteasomeassembly on gel-filtration and native gel analysis. In contrast, reduced expression ofFOXRED2 rescues Aβ-induced inhibition of proteasome activity. FOXRED2 is anunstable protein with two degradation boxes and one KEN box, and its N-terminaloxidoreductase domain is required for proteasome inhibition and cell death. Ectopicexpression of FOXRED2 induces ER stress-mediated cell death via caspase-12, which isinhibited by Salubrinal. Further, down-regulation of FOXRED2 expression attenuates Aβinducedcell death and ER stress responses. These results suggest that up-regulatedFOXRED2 inhibits proteasome activity by interfering with 26S proteasome assembly tocontribute to Aβneurotoxicity via an ER stress response.246 Korean Society for Biochemistry and Molecular Biology