toward eggs is a vvidespread phenornenon kno-n in most animals as well as lowcr plants whiLhand plays important roles in ensuring the fertih7ation However the mechanigms ot sperm Lhemotaxib are poorly understood In thc agcidian Cio]aintestinahs the sperm activating and attracting faLtoi (SAAF) derived lrom maturcd eggs has been aheddy idenufied Using a nc" teLhnique for the real tirne imaging oC FCa2+]i "hich ig a key iegulator tn sperni motility we revealed that transient [Ca2+1i increases ]n

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... pLnii ce]ls were elicited in a medium that has the conLentration gradient of SAAF Wc algo found that a se-es of stereotypic rcsponses ot flagelldr waveformb (turnmg and straight swimmmg) fo11owed the Ca respongeg aiter a short delayts With Lomputer sirnu]ationb babed on the detailed observations of Ca2+ Tesponses and flagellur wave toinis and swimmmg path changes of spermatozoa gpeTm gwimming we tested new modelg tor the Lhemotactic swimmmg behaviors of speimiatotoa It vvab suggested that Ciona gpermatotoa first detect the decrease of attractant eonLeutrations and that it tnggeied the Ca2+ mediated stereotype Lhdnges of flagellar wai efoinig and ieorientauon of sperm swimmmg path ethciently towftrd the eggs 2P 159 t BuOOH aspt [t:-F=> F iJ 7MSfi ttQItO,Pilit Medsurements of mitochondrial pcrmeablhty change mduced by t BuOOH Yoshihiro Matsunomote (1) Xiaolei Shi (1) Chisake F-ita ( 1) Yobhihiro Ohta (1) (Cl) D-ofBioteeknoloey andLde Sctence 7okyo Vnivtrwty ofAgncutture) Smce the mtegnty ot the innLr mitochendllal membrane ensures the mamtLnanLe of proton motave force acrogg the membTane the permeability of the membranc is congideied to be highly regulated Oxidative stress ig a main cause of ischemialieperfusion ingury and supposed to merease the permeabi]ity of inner mLtoLhondnal membranes The mcreage in the permeabihty however has bcLn suppoTtcd by iesu]ts obtained with mdirect measurements of Lhe permeability Here we report the direet measurementb of the permeabihty changeg in the inner mitochondnal rnembrane m C6 glnma cdlg To deteLt the permeability changc we observed the release of calcem a hydTophilie fiuorescent molecule from mitochondlla Pllor to oxidative stress cells were ]oaded with Lalcem AM t BuOOH wag added as oxidatlve stress and mduced cell death that cnded up with the rupture ot the plasma membrane By measunng calcein fluoicseence m mttochondna we observed that tBuOOH mduced the transient and repe"t]ve ]ncrease m the mner membrane permeability at f]rst and then provoked the long lastang incTcagL in the permeabLht) before the rupture of the plasma membrane SmLe the later mcrease in the permeability was suppressed by cyclosporme A wc conclude that the later inLreabe cerresponds to so callcd pLrmLabitity uansMon The details vvill bc disLussed 2P157ktsOite9eeeeeueUkwaEe9me"-blL7](A-BIOMIMETIC FUNCTIONAL FIBROUS GEL CONSTRUCTED BY HIERARCHICAL SUPRAMOLECULAR ASSEMBLY OF ORGANICMOLECULES Datsuke Kiriva (1) H]roak] Onec (1) Masate Ikeda (2) ltaru Hamachi (2) ShoJi TtkeuLhi (1) (CI) lnstmde of lndustnat Science wae Vntversity of lokyo C2) Gtadz{ate School of Engmeenng Klote V}llverhtn) There is long history ot ennulating ndtuial organisms for design of practical materials and systems The Teagons are two hneb the firbt one is that natural orgamsms pioduce highly orgamzed hierarchical straetuiLg whiLh ghow the sophisticated properties such as elasticity and ngidrty the sLcond is that thLge structures show dynamic funchons suLh as selective diffusion of molecules and self ]epamng of damaged area Despite the extengive studies it ig stdl lare to make the artificial rnfttenals exhibitang not only the biomimetie structures but the biomimetic dynamic tunctions In thig papu we will dementstrate the strategy to eonstruLt artificial quasi biofunctaonal fibroug gupramo]ecuhr gel whJLh show the dynamic functions ]ike naturai matenals The gel is generated by the hierarchical asgembly moleculemolecular aggcmbled nano si/ed hber -"m sized fibrous gel' The component moleLules (gelators) pdcked each other by the hydrogen bendmg and hydTophobic mteractions to form nane sized fibrous sti ucturc dnd this nano structures are connected each other by Ca(II) iun te ferni hierarchical um siLed fibrouts hydroget The constituent moleeule is reportcd previoubly by Hamachi et al <I Am Chenf Soc 20e9 i31 5580) which exhibitg sol gel hansitioq by external stimuh such as pH change and hght uradiation We have also examined the ability o[ thc fibious gel to iebpond to external stirnu]] ftnd geTeLtively diffuse dyes with d!rectional characteT 2P160 Chisako F-ita (1) ofBiotechnologx Anttbody Lab t-BuOOH ssigmatMtufi[:foft6 CypD Oift:1] :-F=)tFU 7{:at6ATPgere.xopee5 The role of Cyclophilin D in tBuOOH induLed Lell death its ]nvolvementmmitoLhondrialATPsupply Kiyotaka Machida (2) Hiroyuki Osada {2) Yobhihllo Ohta {1) (CIJ Dtv aFut LtOle Sclence fbdyo UntLersiA ofAgnculture anti 7lrchnelog) (2) RikLn) Cyclophihn D (CypD) is a mitoLhondndl matnx located enLyme that has speciai roles in regulatmg cell death It ]s known that CypD suppresses apoptotlc cell dcath by inhibiting Bax bmding to the mitochondria On the other hand it promoteg neLrotiL Lell death through mteractmg with the mner membrane protems and forming a huge pore callcd Membrane Permeabdity Transition Porc (MPTP) OnLe MPTP is opened mitochondna drssipatc the membrdne potential and lose oxidaLivc phosphorylation aLtivity The precse rnechanism of ceii dedth regulatJon by CypD is still uncleai but elucidatmg itb role may let us discovcr new mLthod Jn Lontroltmg cell death Herc we gtudied the iole of CypD m tert butylhydroperoxidc (t BuOOH) a well known oxidative stresg generatoi induLed cell death We preparcd C6 g]ioma celts over expressmg wild type of CypD eniymatac activity deficient CypD and those with empty vector We cornpared cell death rate among these cells and mvestigated the pathway of mtracellulaT Lcll dedth bignalmg by usmg fluoregeenLeimag]ngteLhmque We found that CypD acts as a cell dcath promoter with its enzymatac actrviLy and that this effect is different to the Ml'I'P opening ginLe its effects was observed before the disgipanon ot membTane potLntial We will discuss al}out the new rolc of CypD in regulating oxidative stress mduced cell deaLh and its relationship betweenothersignals 2P 158 vavama-ti ± i)YijOfits-&Ol mainVAJVgeut Single cell level analysis of adaptation in chcrnoaLtraetant signaling mDiLtyostehum Keita Kdmmo (]) Sateslii Sawal (2) ((i) Grad!iak Schooi ofArts and Scjences [huversiij of Tokyo r2) Cradttat[ SLheol ofArts and S"ences UnrvErsTo of ToOo JST[RATO ComptexS}stemsBiology} In Dictyobtelium discoideum excitatory and ogcillaLoiy LAMP gyntheg]s of chemoattraLtAnt LAMP mediates eell cell commumcatation and guidcs chemotaxis It has becn shown that the transient pulse of LAMP mduLed LAMP bynthesib (cAMP relay) are highly adapnve The synthesig ot cAMP s cl]ut ¢ d by the relative mcrcase in the extraLellular cAMP leNel and its dynamic range enLompass 4 orders of magmtude However the detail dynamical features and thc mechanism of thib addptive response remain elusive In this study we re examine the adaptave property of the cAMP relay rLsponsc at the single cLll level usmg FRET basLd hve Lell imagmg of cytosohc cAMP By first allowmg cells to adapt to a constant level of cAMP then elevatang it furLher to see therr Tesponse vve fmd that single Lells exhibit LAMP relay response at pre stimulus extracellular cAMP concenLranons thaL range over three orders of magnitude The magmtude of the response depends on thc absolute conLentiationg pnor to the mereage in sumulation The laigetst iesponse is observed when cells had adapted to e.1nM or ]egs At h]gher concentrdnons of extracellular cAMP cells fail to return to the prestimulus gtate and showcd oscillatory behavio] regardless of tht hibtory of the dynarnics in cytosolic cAMP Wc digcugg how the obgeived adaptive Tegponge together with the Lharacteristic phase response curse help coordinate the multicellularoscillationgandchemotaxis 2P 161 ENbtional Coliege of Technology C4) Jnsnt"te or Symbtoltc SLience and 7eLhnoiog) Tbbo Vmveryio of Agrteulture and lechnoleLy) Parameaum onL of piototoan ciliate approximately O 2 milhmeters m length swims by beatmg cihd on the cell surface The parame"um gwimming behayior can be obgerved by llsing optical mieroscope or even with naked eye under guitab]e illumL"a"om condiuon Patame"um mamly swimg stn]ght and oecasionally changes the swimmmg direction spontaneously The drrectaonal Lhange is Laused by reversdt motton ef the partial ellla le 20 seeonds mtervdls m water on avcrRge duc to environmental thermal fluctuation enhanced mside the cell Therefore the swimmmg behavior of pmameaum is deseribed by measurement of the ve]outy when the Lell swims straight and the frequLncy of the directaon change Aparame"um teels its surrounding enviro]mental changes and creates actaon accordrng to those external changeg It means the paramecium swimmmg behdiioi reflectb the sanie size stmcture as paramecium teeling betwcen maLrogLopie level and miLrogLepic level phenomena That is why to quantify by measurement of the paramecium swimmmg behavior can be a new method of analyzmg vibLous bolutaells or structural phase transition proccsg In this resLarch swimrning traJcLtory ot a gmg]e pardmecJum withm the enclosure omscM69 -S131 NII-Electronic