SEMINAR ROOM
ã»ãã ㌠宀
æçšçç©ã®ã²ãã ç 究ã®çŸç¶-2
æ¯èèäºæåå¶åŸ¡ç³»ã®DNAã ã€ã¯ã㢠ã¬ã€è§£æ ãäžå¿ ã«
è€ç°æ³°å€ªéçŠå±±å€§åŠçåœå·¥åŠéš
æ¯èè ã¯, ã°ã©ã éœæ§èã®ä»£è¡š ãšããŠ, å€§è žè ãšäžŠã¶
åºç€ç 究ã®æŽå² ããã£ãŠãã. ç¹ã«, 现èååã®ã¢ãã«
ãšã¿ãªãããèå圢æã®ååã¬ãã«ã§ã®ç 究 ã¯, ä»ã®ç
ç©ã«ããã现èåå ã®ç 究 ãåé§ãã ãšã ãã. ãã
ã«, æ¯èè ã¯Î±-㢠ãã©ãŒãŒããããã¢ãŒãŒãª ã©ã®èäœ
å€é µçŽ , ããã ãç³»æçç©è³ªãªã©ã®çç£è ãšããŠ, éèŠ
ãªå¿çšåŸ®çç©ã®äžã€ã«æ°ããããŠãã.
æ¥æ¬ ã«ã ããæ¯èè ã®ã² ãã ç 究 ã¯, 1991幎 ã² ã
ã å šå¡©åºé å決å®ã®ããã®ã¢ãã«çç© ãšããŠå ãäž ã
ãããããšã«ç«¯ ãçºã ã. åœæ, æ¥æ¬§ååãããžã§ã¯
ããçµç¹ããã. ãã®ãããžã§ã¯ ãã®é 調ãªé²å± ã«ã
ã, 1997幎 ã«æ¯èèã²ãã ã®å šå¡©åºé åã Nature èª ã«
å ¬è¡š ãã(1ïœ3), æ¥æ¬§ ã§ãã®ããŒã¿ããŒã¹ ãæ§ç¯ ããã
(http://bacillus.genome.ad.jp, http://genolist.pasteur.
fr/SubtiList/). ãã®å¹Žä»¥æ¥, æ¯èèç 究 ããã¹ ãã²ãã
ã·ãŒã±ã³ã¹æ代 ã«å ¥ ã, æ¯èèã²ãã ã®æ©èœè§£æãç®æ
ãæ°ããªæ¥æ¬§ååãããžã§ã¯ ããçµç¹ããããªã©, ã²ã
ã é åæ å ±ãåºã«ããæ©èœè§£æã粟åçã«æšé² ãã, 5
幎ããŸããçµéããŠãã. ãã®ããã«æ¯èèã®ã²ãã ç
究ã¯, åœéçãªè²¢ç®åºŠããéã¿ãŠã, æãåœã®åæ žçç©
ã®ã²ãã ç 究ãå å° ããŠãããšããã.
ãã¹ ãã²ãã ã·ãŒã±ã³ã¹æ代ã®å¹éããšãšãã«, ã²ã
ã æ å ±ãåº ã«ããŠæ¬¡ã®ãããªè§£æãè¡ãªãããŠãã.
(1)ã²ãã ã®å šå¡©åºé åæ±ºå® ã«ã ãååšãæ ãã ã«ãª
ã£ã, å€ ãã®æ©èœãæšå®ã§ ããªãæ°èŠéºäŒåã®æ©èœè§£
æ. æ¯èèã²ãã ã®å šå¡©åºé åãæ ããã«ãªã£ãçµæ,
4,100ã® èçœè³ªéºäŒåãåå® ãã, ãã®åæ°ä»¥äžãæ©èœ
ãç¹å®ã§ ããªãæ°èŠéºäŒåã§ãã£ã. ããããéºäŒåã®
æ©èœè§£æãç®æ ã, äœç³»çã«éºäŒåç Žå£æ ªã®ãã³ã¯ãäœ
æ ã, ãã®è¡šçŸåã®ã¹ã¯ãªãŒãã³ã°ãè¡ãªã£ã.
(2)ã²ãã é åæ å ± ãåºã«ããŠ, çš®ã ã®å¹é€æ¡ä»¶ã§å¢æ®
ããã现èã®ããããªãŒã ã解æ ã, ãããªãèçœè³ªã
åæ ãããŠããããç¶²çŸ çã«æããã«ãã. æ¯èèã®ã
ãããªãŒã 解æã¯, ã²ãã ã®å¡©åºé åæ±ºå® ãšãšãã«çæ
544 ååŠ ãšçç© Vol. 40, No. 8, 2002
ãã, æãåœã欧å·ã§èçœè³ª2次 å é»æ°æ³³åã®ã¹ããã
ã®åå®ãª ã©ã粟åçã«è¡ãªãããŠããŠãã.
(3)çš®ã ã®å¹é€æ¡ä»¶ã§å¢æ® ããã现èã§ã®ã²ãã ã®å šéº
äŒåã®çºçŸ ãæ ãããšã ããã©ã³ã¹ã¯ ãªã ããŒã 解æ
ã, DNAã ã€ã¯ãã¢ã¬ã€ (ãããã¯ãã¯ãã¢ã¬ã€) æè¡
ã®é²å±ã«ããå¯èœ ã«ãªã£ãŠãã. æãåœã§ ã, 2幎 åã«
æ¯èèã®ãã€ã¯ãã¢ã¬ã€è§£æãå¯èœ ãšãª ã, 粟åçã« ã
ã©ã³ã¹ã¯ãªã ããŒã 解æãé²ã ãããŠãã.
(4)åææ©åšã®çºå± ã«ãã, 现èå ã®å€æ°ã®ä»£è¬ç£ç© ã
çµç¹çã«å®éåããããšãå¯èœ ãšãªã£ãŠãã. ãã®ã¡ã¿
ãããŒã 解æã¯, ã²ãã é åæ å ±ã«åºã¥ãã解æã§ã¯ãª
ãã, 现èã®éºäŒåçºçŸå¶åŸ¡ ãç¶²çŸ çã«æã, ãã®ãã
ãã¯ãŒã¯ãæ§ç¯ããããã«ã¯å¿ é ã®è§£æã§ãã. æè¿,
æ¯èèã察象ã«, ã¡ã¿ãããŒã 解æãæ¬æ Œçã«å§ãŸã£ãŠ
ãã.
æ¬çš¿ã§ã¯, æ¯èèã®æ°èŠéºäŒåã®äœç³»çãªæ©èœè§£æ,
ããããªãŒã 解æ, ãã©ã³ã¹ã¯ ãªã ããŒã 解æ, ããã«
ã¡ã¿ãããŒã 解æãžãšçãé²ãã. ãã®ãã¡çè ããåŸ
äº ããŠãã, äœç³»ç㪠ãã©ã³ã¹ã¯ãªã ããŒã 解æ ãäžå¿
ã«è¿°ã¹ã.
æ¯èèã®æ©èœæªç¥éºäŒåã®äœç³»çæ©èœè§£æ
æ¯èèã²ãã ã®å šå¡©åºé åã決å®ãã1幎 åã®1996
幎, å¥è¯å 端ç§åŠæè¡å€§åŠé¢å€§åŠã®å°ç¬ åææ ãšãã©ã³
ã¹INRA (Institut National de la Recherche Agrono-
mique) ã® Ehrlich å士ãäž»å¬ ããŠ, æ¥æ¬§ã®æ¯èèç 究
宀 ã«ããåå ãããžã§ã¯ã ãæ¯èèã²ãã ã®æ©èœè§£æã
ãçµç¹ããã. ãã®ãããžã§ã¯ ãã¯, æ¯èèã²ãã ã®é
å決å®ã®çµæåå®ããã4,100ã® èçœè³ªéºäŒåã®ãã¡,
åæ°è¿ ãã«ã®ãŒãæ©èœæªç¥éºäŒåãäž»ããã¿ãŒã²ã ããš
ããŠ, ãã®æ©èœãçµç¹çã«è§£æãã ãšãã ãã®ã§ãã£
ã(3ïœ8). å ·äœçã«ã¯, æ¥æ¬§ã§åäžã®ãã©ã¹ ãããã¯ã¿ãŒ
(pMUTIN) ãçšããæ¿å ¥éºäŒåç Žå£æ ªã®ãã³ã¯ãäœæ
ã, ãã®è¡šçŸå ãã¹ã¯ãªãŒãã³ã°ãããã®ã§ãã. 1999
幎 ãŸã§ã®3幎 éã®ååç 究ã«ãã, æ¥æ¬§ã§åã 1,000ã
ãŸãã®æ¿å ¥ç Žå£æ ª ãäœè£œ ã, ãã®ç·æ°ã¯2,072æ ª ã«é ã
ã. 欧å·ã§ã¯æ¯èèã²ãã ãããžã§ã¯ ãã®åç·šã®ãã,
ãããªãç Žå£æ ª ã®äœè£œ ã¯è¡ ãªãããªã ã£ãã, æ¥æ¬ã§
ã¯ç¶ç¶ ãã, æ¯èèæ©èœæªç¥éºäŒåã» ãšã ã©ãã«ã ãŒ
ãã, 2,776éº äŒåã«ã€ããŠã®æ¿å ¥ç Žå£æ ªãã³ã¯ãå®æ
ãã.
ãã®ç¶²çŸ çæ¿å ¥ç Žå£æ ªäœè£œã®éçšã§, ç Žå£ ã«äŒŽãèŽæ»
ã«è³ ãéºäŒåãç¹å®ãããŠãã. ãã ããå¿ é éºäŒåã§
ããããšã確èªããããã«, ãã®éºäŒåã®çºçŸ ãIPTG
(isopropyl-β-D-thiogalactoside) äŸåæ§ ã«ããå€ç°æ ª
ã«ã€ããŠ, ãã®å¢æ®ãIPTGäŸ åæ§ã«ãªãã ã©ãããæ€
å® ãã. ãã®çµæ, æ¯èèã®å¯æ é€å¹å°ãçšãã37âã§
ã®å¢æ®ã«å¿ é ãª132ã® éºäŒåãåå®ã ãããšãã§ãã.
ãã®ç¥èŠ ãšæ¢ç¥éºäŒåã®æ å ± ãçµ±åãããš, 270ã® éºäŒ
åããã®å¢æ®æ¡ä»¶ã§ã®å¿ é éºäŒå ãšã¿ãªããã(8). ãã®
ææ ã¯, äžã€ã®çç©ã®å¿ é éºäŒåã» ãããå®éšçã«åã
ãŠæããã«ãã ãã®ãšããŠ, éåžžã«å€§ ããªæ矩ããã£ãŠ
ãã. ããã«ãã ãã®å¿ é éºäŒåã® ãã¡, 28éº äŒåãæ©
èœæªç¥ã§ãã, ã·ã°ãã«äŒéã«éèŠãªåœ¹å² ãæãããŠã
ãGTPçµ åèçœè³ªãã¡ããªãŒã®9éº äŒåã®ãã¡6éº äŒ
åããã ãã®æ©èœæªç¥å¿ é éºäŒå ã«æ°ããã, ãŸã1察
ã®äºæåå¶åŸ¡ç³»ã®éºäŒåãå« ãŸãã. ãããã®å¿ é éºäŒ
åã®æ©èœè§£æ ã¯, ä»åŸã®éèŠãªç ç©¶èª²é¡ ãšãª ããšãšã
ã«, ã°ã©ã éœæ§ç åèã«å¯ŸããååŠçæ³å€ ãéçºããäž
ã§ã®ã¿ãŒã² ããéºäŒå ãšã㊠ã泚 ç®ãããŠãã.
æ©èœæªç¥éºäŒåã®æ¿å ¥ç Žå£æ ª ã®ã ã³ã¯ãå®æ ããã®
ã§, ãã ãç Žå£æ ª ããããžã§ã¯ ãã«åç»ããåç 究宀ã«
é åž ã, åã ç¬ èªã«éçº ãããã ãã³ãŒã«ãçšããŠ, çµ
ç¹çãªå€ç°æ ªã®è¡šçŸåæ€çŽ¢ ã粟åçã«æšé² ããã. æ¥æ¬
ã§ã¹ã¯ ãªãŒãã³ã°ãããçŽ1,000ã® å€ç°æ ªã®ãã¡, 40%
匷ã«äœ ããã®æ§è³ªã®å€åãèª ãããã(5,7,8). ãããã®ã¹
ã¯ãªãŒãã³ã°ã®ãã¡, ççŽ æºã®è³åèœãèå圢æ ãšçºèœ
èœã®æ¬ æã«ã€ããŠã¯ç¹ç°çãªæ©èœ ã«è¿«ãããšã容æã§ã
ã, å®éãã®ãããªç 究ææãæ ãããã€ã€ãã. ãã®
ãæ¯èèã²ãã ã®æ©èœè§£æããããžã§ã¯ ãã®ææã¯, æ¥æ¬
ã§ã¯åè¿°ã®ããŒã¿ããŒã¹ (http://bacillus.genome.ad.
jp) ã§çºè¡šãã, 欧å·ã§ã¯æ°ããªããŒã¿ããŒã¹ (http://
locus.jouy.inra.fr/) ãäœæããã.
æ¯èèã®ããããªãŒã 解æ
ããçç©ã®å šã²ãã é åã決å®ãããš, ãã®çŽ°èã®è
çœè³ªåç»ã2Dã² ã«ã«å±é ã, ã¹ãããäžã®åŸ®éèçœè³ª
ã«ã€ããŠNæ« ç«¯ ã®ã¢ ããé žé åãè¥å¹²æ±ºå®ã ãããšã«
ãã, 察å¿ããéºäŒåãåå®ããããšãå¯èœ ãšãªã. ãŸ
ã, ããã埮éèçœè³ªãé åç¹ç°çãããã¢ãŒãŒã«ãã
åæ ã, æçã®å€§ ããã質éåææ© (MS) ã§æž¬å®ããŠã²
ãã é å ãšç §åãã, ãã¹ãã£ã³ã¬ãŒããªã³ãæ³ã«ãã
察å¿éºäŒåã®åå® ãã§ãã. æ¯èèã§ã¯, å°ç¬ åææ ãš
å®®åŽå»ç§å€§åŠã®äžå±±ææ, ãã€ã Ernst Morits Arndt
倧åŠã® Hecker ææãäžå¿ ãšãª ã, èçœè³ª2次 å é»æ°æ³³
åã®æšæº ãã ãã³ãŒã« ãçš ããŠ2Dã² ã«äžã®çŽ500ã¹
ãã ãã®èçœè³ªãéºäŒå ãšå¯Ÿå¿ã¥ããã, Ernst Morits
Arndt å€§åŠ ã§ ãã® ã㌠ã¿ã ㌠㹠ãäœæ ãã ㊠ã ã
ååŠ ãšçç© Vol. 40, No. 8, 2002 545
(http://microbio2.biologie.uni-greifswald.de:8880/).
ããã«æ¥æ¬ã§ã, ã«ã¿ãã©ã€ ãæå¶äžã«ããèçœè³ª, è
å圢ææã®åã¹ããŒãžã«ç¹ç°çã«åæãããèçœè³ª, å
æ³èçœè³ª, 现èå£ãæ§æããèçœè³ªãªã©, ããç¹å®ã®çŽ°
èæ©èœã«é¢é£ããéºäŒå矀ãæ€çŽ¢ããããã«2次 å é»æ°
æ³³å ãå©çšããè©Šã¿ã, ã ãã€ãã®ç 究宀ã§ç©æ¥µçã«é²
ããããŠãã. ãã ãæ¥æ¬ã®ããããªãŒã 解æ ã®ææ
ã¯, ç·èª¬ ãšããŠãŸãšããããŠããã®ã§ãã¡ããåç §ãã
ãã(5,9).
æè¿ã®åææ©åšã®ãããªãçºå±ã«ã ã, 现èã现èåš
å®ãã® ãã®ã«å«ãŸããèçœè³ªãçµç¹çã«åå®ããããšã
å¯èœ ãšãªã£ãŠãã. ãã®æ¹æ³ ãšã¯, 1次 å ã®SDSé» æ°
æ³³åã§åé¢ ããåŸ, åãã³ ããå ãåºã, æœåº ã»åé¢ ã
ãèçœè³ªæ··åç©ããããã¢ãŒãŒã§äœååå, æ¶²äœ ã¯ã©ã
ãã°ã©ãã£ãŒ (LC) ã§åé¢åŸ, ã¿ã³ãã MSã« ããããš
ãããã®ã§ãã. å°ç¬ åç 究宀 ãšæå倧åŠã®æž¡éšç 究宀
ã§ã¯, ãã®æ¹æ³ãçšããŠæ¯èèèåãæ§æããèçœè³ªçŽ
200çš® é¡ã®åå®ã«æå ããŠãã (æªçºè¡š). ãŸã, èçœè³ª
è€åäœãåé¢ã, äžèšã®LC/MS/MSã« ãããããšã«ã
ã, ãã®è€åäœã®æ§æèçœè³ª ãåå®ããè©Šã¿ãé²ãã§ã
ã. ããã«, èçœè³ªéã®çžäºäœçšãæããã«ãããã,
æ±äº¬èŸ²æ¥å€§åŠã®åå·ç 究宀ã§, èçœè³ªéã®çžäºäœçšã®æ
ç¡ãæç¥ããé µæ¯2ã ã€ããªããç³»ã®æ¯èèã²ãã ã©ã€
ãã©ãªãŒãäœæãã, èå³ããçžäºäœçšãç¹å® ãããŠã
ãŠãã (æªçºè¡š).
æ¯èèã® ãã©ã³ã¹ã¯ ãªã ããŒã 解æ
1. æ¯èèã®ãã€ã¯ãã¢ã¬ã€æè¡ã®éçº
ãæ¯èèã²ãã ã®æ©èœè§£æããããžã§ã¯ ãã®äžç° ãšã
ãŠ, æ¥æ¬ã§ã¯çŽ500kbã« ãããé åã®éºäŒåã®ç¶²çŸ çãª
ããŒã¶ã³è§£æ ãå®æœ ãã(5,6), http://bacillus.genome.
ad.jp ã«ããŒã¿ããŒã¹å ãããŠãã. ãã®ç 究ææ ãšæ¯
èè ã²ãã ã®å šå¡©åºé åãåº ã«ããŠ, çè ãã¯æ¯èè
ã®DNAã ã€ã¯ãã¢ã¬ã€è§£ææè¡ã®éçºã«å ãçµ ãã .
2000幎 åé , æ¯èèDNAã ãããäœæ ã, ãã®å¹Žã®å€
ã ãä¿¡é Œã§ããDNAã ã€ã¯ãã¢ã¬ã€è§£æãè¡ãªããã
ãã«ãªã£ã. çè ããéçº ããæ¹æ³ ã¯, mRNAã ããª
(A) æ«ç«¯ããããªãããã«mRNAã 粟補ããããšãå°
é£ãªåæ žçç©ã®ãã€ã¯ãã¢ã¬ã€è§£æã§, éç¹ç°çãªãã€
ããªãã€ãŒãŒã·ã§ã³ã®ã·ã°ãã«ã«ããã ãã¯ã°ã©ãŠã³ ã
ãæããæ¹æ³ ãšããŠæå¹ã§ã ã, 次ã®ãããªæ¹çãå ã£
ãŠãã(10ïœ12).
(1)è¢å è²çŽ Cy3ã ãã³Cy5㧠ã©ãã«ããcDNA調 補
ã«2段 éè¢å ã©ãã«æ³ãçšãã. ãŸã, æšæºRNAãš å®éš
RNAã, 㢠ããã¢ãªã«-dUTPã çšããŠé転åã«ããã¢
ãã㢠ãªã«å ãã. 次ã«, åã ã®ã¢ ãã㢠ãªã«å ãã
cDNAã, ããããN-ã ãããã·ã¹ã¯ã·ã³ã€ãã-Cy3
ãšããããã·ã¹ã¯ã·ã³ã€ãã-Cy5㧠ã«ãã ãªã³ã°ãã
è¢å ã©ãã«ãã. ãã®æ¹æ³ ã«ãã, åŸæ¥ã®Cy3-dUTP
ãšCy5-dUTPã çšãã1段 éã§ã®cDNAã® è¢å ã©ã
ã«æ³ã§èŠ ããã, åºè³ªã®éãã«èµ·å ãã埮åŠãªé転å䌞
é·åå¿ã®éãã«ããå®éšèª€å·®ãé€å€ã§ãã.
(2)é転ååå¿ã®ãã©ã€ã㌠ãšããŠ, æ¯èèãããäœæ
æã«çšããå š4,100éº äŒåãå¢å¹ ããããã®ãã©ã€ããŒ
ã® ãã¡, mRNAã« çžè£çãªãã©ã€ããŒã®æ··åç© ãçšã
ã. ããã«, èç±æ§ã®é転åé µçŽ ãçšããåå¿ã60âã§
è¡ãªã, ãŸãDNAã ãããšã®ãã€ããªãã€ãŒãŒã·ã§ã³
ã70â㧠è¡ãªã£ã. ãã®ããã«ããŠ, éç¹ç°çãªãã€ã
ãªãã€ãŒãŒã· ã§ã³ãã ã©ããŒã°éã®ã¯ãã¹ãã€ããªãã€
ãŒãŒã·ã§ã³ãããªãæ ããããšãã§ãã.
2. æ¯èè転åå¶åŸ¡ã ã ãã¯ãŒã¯è§£æãç®æãDNAã
ã€ã¯ã㢠ã¬ã€è§£æ
çè ãã¯, 2000幎 床 ããæ¯èèã®è»¢åå¶åŸ¡ã ããã¯
ãŒã¯ã®è§£æ ãç®æããããžã§ã¯ ãã«å ãçµãã§ãã. æ¯
èèéºäŒåçºçŸå¶åŸ¡ ãããã¯ãŒã¯ã®æ ¹å¹¹ ã¯, å š18å ã®
RNAã ãªã¡ã©ãŒãŒã®ã·ã°ãå å, 35å ã®äºæåå¶åŸ¡ç³»
ã®å¿çå¶åŸ¡å å, ããã³200å ã ãŸãã®HTH (helix-
turn-helix) èçœè³ªã«ãã圢æãããŠãããšè ãããã.
ã·ã°ãå åã¯, 现èã®å¢æ®ãèå圢æ, ãããã¯ç°å¢é©
å¿ã«ãããéºäŒåã®è»¢åå¶åŸ¡ãæ¯é ã, äºæåå¶åŸ¡ç³»ã®
å¿çå¶åŸ¡å åãHTHè çœè³ªçŸ€ã¯, åã ã®åäžã«ããéº
äŒåã®è»¢åå¶åŸ¡ ãé ããŠ, æ é€çŽ ãªã©ã®çš®ã ã®ç°å¢å€å
ãç¹æ®ç°å¢ã«å¯Ÿå¿ãã. ãã ãã®åæ°ä»¥äž ã¯, æ¢ç¥ã®å¶
埡èçœè³ª ãšã®çžåæ§ããå¶åŸ¡èçœè³ªã§ãããšæšå®ããã
ãã®ã§ãã, åã ã®å¶åŸ¡èçœè³ªãå ·äœçã«ã©ã®éºäŒå矀
ã®å¶åŸ¡ ã«é¢ãã£ãŠããããªã©ã®æ©èœã«ã€ããŠã¯äžæã§ã
ã. æ¯èèã®è»¢åå¶åŸ¡ã ããã¯ãŒã¯ã¯, ãããæ©èœæ¢ç¥
ããã³æªç¥ã®å šå¶åŸ¡èçœè³ªãæ¯é ããã¬ã®ã¥ãã³çºçŸã®
ç·åã§ãããšèããã, ãã®ãããã¯ãŒã¯ãæããã«ã
ãã«ã¯, ãããåã ã®ã¬ã®ã¥ãã³æ§æéºäŒåããªããã³
åäœ ã«æŽç ã, å¶åŸ¡ã®æ§çžãææ¡ããããšãå¿ é ãšãªã£
㊠ãã. ãã®ããã®æ段ã, DNAã ã€ã¯ãã¢ã¬ã€è§£æã«
ããçš®ã ã®å¹é€æ¡ä»¶ã§çºçŸããšãã«ããéºäŒåã®ã¯ã©ã¹
ã¿ãªã³ã°ã§ã ã, å¶åŸ¡èçœè³ªéºäŒåã®å€ç°æ ª ãçšããæš
çéºäŒååè£ã®åå®ã§ãã.
ãã®ç®çã®ããã«çè ããé²ããDNAã ã€ã¯ãã¢ã¬
ã€è§£æ ã¯, ã«ã¿ãã©ã€ ãæå¶ã®è§£æ, çš®ã ã®ççŽ æºãã
ã³çªçŽ æºã§ã®å¢æ®æã®éºäŒåçºçŸè§£æ, 転åå¶åŸ¡èçœè³ª
546 ååŠ ãšçç© Vol. 40, No. 8, 2002
éºäŒåå€ç°æ ªãçšããæšçéºäŒåã®è§£æ, èåçºèœ ãš
outgrowth æã®çµæçéºäŒåçºçŸã®è§£æãªã©ã§ãã. ãŸ
ãå°ç¬ åãã¯, æ¯èèå¢æ®æ ãšèå圢ææã®çµæçéºäŒ
åçºçŸã®è§£æ, çš®ã ã®ã¹ ãã¬ã¹äžã§ã®éºäŒåçºçŸã®è§£
æ, 転åå¶åŸ¡èçœè³ªéºäŒåå€ç°æ ªãçšããæšçéºäŒåã®
解æãªã©ãå®æœ ãã. äž¡è ã§è¡ãªãããDNAã ã€ã¯ã
ã¢ã¬ã€è§£æã¯ãã§ã«200以 äžãæ°ãã. ãããŸã§ã«çè
ããå®æœ ããDNAã ã€ã¯ãã¢ã¬ã€è§£æã®ãã¡, æ¯èè
ã®ã«ã¿ãã©ã€ ãæå¶(11)ãšççŽ ä»£è¬ã®è§£æ ã¯, ãã§ã«æ¬èª
ã§çŽ¹ä» ãã(13). ãã®ä», å 容çã«ãŸãšãŸã£ãŠãããã®ã
2〠玹ä»ãã.
1) æ¯èèã®æ£ã®è»¢åå¶åŸ¡èçœè³ªã®DNAã ã€ã¯ãã¢ã¬
ã€è§£æ
DNAçµ å転åå¶åŸ¡èçœè³ªã¯, ç¹å®ã®æšçéºäŒåã«å¯Ÿ
ããŠæ£ãããã¯è² ã®å¶åŸ¡ ãè¡ãªã. ãã®äžã§ã·ã°ãå å
ã¯æ£ã®å¶åŸ¡ã®ã¿ãåž ã, ãŸãäºæåå¶åŸ¡ç³»ã®å¿çå¶åŸ¡å
å ãäž»ã«æ£ã®å¶åŸ¡ ãåžããšè ããããŠãã. 転åå¶åŸ¡è
çœè³ªãæ£ã®å¶åŸ¡å å ãšããŠäœåããå Žåã«ã¯, ãã®æ©èœ
ãçºçŸ ããŠããªãå¹é€æ¡ä»¶ã§åŒ·å¶çã«éå°çºçŸ ãã ã
ãš, ãã ãã®æšçéºäŒåã®çºçŸãäžæã ããšäºæ³ ãã
ã. ãããã£ãŠ, å¶åŸ¡èçœè³ªéºäŒå ã匷å¶çã«çºçŸ ãã
ãå Žå ãšãããªãå Žå ãšã§DNAã ã€ã¯ãã¢ã¬ã€è§£æ ã
è¡ãªãã°, çºçŸãäžæ ããéºäŒå ãå¶åŸ¡èçœè³ªã®æšçéº
äŒååè£ ãšèããããšãã§ãã.
ãã®DNAã ã€ã¯ãã¢ã¬ã€è§£æã®é·æ ã¯, å¶åŸ¡èçœè³ª
ã®æ©èœãäžæã§ããã®æšçéºäŒå ãæœåºã§ã, ããæšç
éºäŒå矀ã«æ¢ç¥ã®éºäŒåãå«ãŸããŠããã°, å¶åŸ¡è çœè³ª
ãåžãæ©èœãé¡æšã§ããããšã«ãã. ãã£ãšã, æ¢ ããŠ
ããæšçéºäŒåã, å¹é€å®éšæ¡ä»¶ã§åŒ·å¶çã«çºçŸ ããã
å¶åŸ¡èçœè³ªä»¥å€ã®èçœè³ªã®å¶åŸ¡äžã«ããã°, ããšãæšç
éºäŒåã§ãã£ãŠ ãæœåºã§ããªãããšã«çæããªããã°ãª
ããªã. ãã®åŒ·å¶ çºçŸç³» ãçš ããæ£ ã®å¶åŸ¡è çœè³ª ã®
DNAã ã€ã¯ãã¢ã¬ã€è§£æ ã«æ ãé© ããŠãããšèããã
ãã®ã, éåžžã®å¹é€æ¡ä»¶ã§ã¯äœåããŠããªã ãšè ããã
ãECF (extracytoplasmic function) ãã¡ããªãŒã®ã·
ã°ãå å矀 ãš, äºæåå¶åŸ¡ç³»ã®æš çéºäŒåã§ãã£ã.
ECFã ã¡ããªãŒã®ã·ã°ãå å矀 ã«ã€ããŠã¯, æœåº ãã
æšçéºäŒåã®ç¶²çŸ çãªè§£æ ãçµäº ããŠããã, èªé¢ã®éœ
å ã«ãã, ããã§ã¯äºæåå¶åŸ¡ç³»ã®ãã€ã¯ã㢠ã¬ã€è§£
æ(12,14)çµæ ã«ã€ããŠè©³ ããè¿°ã¹ã.
äºæåå¶åŸ¡ç³»ã¯, 现èãã¯ããé µæ¯ãæ€ç©ã«ãåº ãå
åšãã. ããã¯å€çã®ã·ã°ãã«ãæç¥ ããŠèªå·± ãªã³é žå
ããã»ã³ãµãŒãããŒãŒ ãš, ãã® ãªã³é ž ãåãå ãæšçéº
äŒåã®çºçŸå¶åŸ¡ã«ãããå¿çå¶åŸ¡å å ãšã ã2〠ã®æå
ããæ ãç«ã€ç³»ã§ãã. æ¯èè ã«ååšãã35å ã®äºæ
åå¶åŸ¡ç³»ã®äžã§, æå ã«åŒ·å¶çºçŸç³»ã§ã®ãã€ã¯ãã¢ã¬ã€
解æãäœåããã ã©ãããæ€èšããã®ã, ãã ãŸã§ãã
ç 究ãããŠãã DegS-DegU ç³»ã§ãã.
å³1㫠瀺ããã©ã¹ ãã (pDG148) ã«, degU éºäŒå ãš,
èçœè³ªçåæã®éå§è€åäœåœ¢æã«é¢äžããã·ã£ã€ã³-ã
ã«ã¬ãŒã (SD) é åãå«ãDNAæ ç ãã¯ããŒã³åã,
IPTGã å ããŠå¹é€ã ããš, degU éºäŒåã匷å¶çºçŸã
ãããšã㧠ãã. å³2ã¯, æ¢ç¥ ã® DegU æš çéºäŒå ã®
äžã€ã§ããã¢ã«ã«ãªæ§èçœè³ªåè§£é µçŽ (aprE) ã«ã¬ããŒ
ã¿ ãŒéº äŒ å lacZ ã ãã€é çæ ª ãš degS æ¬ æ å€ ç° æ ª
(ÎdegS) ã«, äœè£œ ãã©ã¹ãã (pDG148-degU) ãå°å ¥ ã,
IPTGæ·» å åŸã® β-ã¬ã©ã¯ ãã·ããŒãŒ (β-Gal) ã®æŽ»æ§ã
å³1 â å¶ åŸ¡è çœè³ªéºäŒ å ã®åŒ· å¶çº çŸç³»(12)
ãã©ã¹ ããpDG148ã¯ å€§è žè ãšæ¯èè ãšã® ã·ã£ ãã«ã ã¯ã¿ãŒã§, ãã® spac ããã¢ãŒã¿ãŒ (Pspac) ã¯å€§è žèã® lac ãªãã¬ãŒã¿ãŒãæ¯èè ã§
äœåããããã«ãã. ãã®ããã¢ãŒ ã¿ãŒã®äžæµ ã«å¶åŸ¡ èçœè³ªéºäŒå (ãã®å Žå degU) ãã¯ããŒã³å ãããã©ã¹ ããã ãã€æ¯èèãIPTG
ãæ·»å ããŠå¹é€ãã ãš, lacI ã« ã³ãŒ ããã ã lac ãªã ãã³ã® ãªãã¬ããµãŒã«ããæå¶ãå€ ã, å¶åŸ¡èçœè³ªéºäŒåã匷å¶çºçŸãã.
ååŠãšçç© Vol. 40, No. 8, 2002 547
è¿œ ã£ããã®ã§ãã. å³2ã ããã ãããã«, éçæ ª ã§
ã¯, IPTG㧠㮠degU ã®åŒ·å¶çºçŸ ã®æç¡ ã«ããã ãã
β-Gal ãåæããã. ãšããã, ÎdegS æ ªã§ã¯, IPTG
ãæ·»å ããå Žåã«ã®ã¿, β-Gal ã®åæãèªãããã. ã
ã®äºå®ã ã, degS ãæ¬ å€± ãã ãããšã«ããå€çããã®
ã·ã°ãã«ãé®æãã, DegU ã ãªã³é žåãããŠããªãç¶
æ , ããªãã¡æšçéºäŒåã®çºçŸãæ ããããç¶æ ã«çœ® ã
ããšãã§ã, ãããŠ, IPTGã æ·»å ããŠãªã³é žå ãããŠ
ããªã DegU ãéå°çç£ã ãããšã«ã ã, ãªã³é žå ã
ãã DegU ãšåãããã«æšçéºäŒåã®çºçŸ ãäžæ ãã
ã ãšèãããã. ããã§, IPTGæ·» å ã®æç¡ã§, å¹é€ ãã
ãã©ã¹ãã (pDG148-degU) ãä¿æããæ¯èè (ÎdegS)
ãã調補 ããRNAã äœ¿çš ããŠ, ãã€ã¯ãã¢ã¬ã€è§£æã«
ãã DegU ã®æšçéºäŒåã®åå®ãè¡ãªã£ã ãšãã, ã ã
ã€ãã®æ¢ç¥éºäŒåãå«ãéºäŒååè£ ãæœåºããã ãšã
ã§ãã(12). ããã«åãææ³ãçšããŠ, DegU ãšäžŠã³è©³ ã
ã解æ ãããŠãã ComA ãš PhoP ã®æšçéºäŒååè£ ã
æœåº ãããšãã, åæ§ ã«è¯å¥œãªææãæ ããããšãã§ã
ã(12). ãã ãã®ææã ã, æ¯èèã«ãããæ©èœæªç¥ãªäº
æåå¶åŸ¡ç³»ã®æšçéºäŒåã®åå® ã«ã, ãã®ææ³ãé©çšã§
ããããšã瀺ããã.
æ¯èèã§ã¯35å ã®å¿çå¶åŸ¡èçœè³ªãåå® ãããŠãã.
ãã® ãã¡, YycF ã¯å¯Ÿå¿ããã»ã³ãµãŒãããŒãŒ (YycG)
ãšãšãã«å¿ é èçœè³ªã§ãã, ã»ã³ãµãŒãããŒãŒéºäŒåã®
ç Žå£ãã§ãã, ãã®åŒ·å¶çºçŸ ã«ããæšçéºäŒååå®æ³ã¯
é©çšã§ããªã. ãŸã SpoOF, CheY, YneI, CheV ãš CheB
ã®5çš® ã®å¿çå¶åŸ¡èçœè³ªã¯, Cæ« ç«¯ã®DNAçµ å ãã¡ã€
ã³ãããã, éå°çºçŸãããŠãæšçéºäŒåã®çºçŸã®å€å
ãæåŸ ã§ ããªã. ããã« SpoOA ãš ResD ã®æšçéºäŒå
矀ã¯, ä»ã®èçœè³ªã®å¶åŸ¡ ãåããŠããå¯èœæ§ãé« ã, ã
ã®æšçéºäŒååå®æ³ã¯æå¹ã§ã¯ãªã ãšèãããã. ãã
ã§, DegU, ComA, PhoP ãå« ãã, 27çš® é¡ã®å¿çå¶åŸ¡
èçœè³ªã«ã€ããŠç¶²çŸ çãªDNAã ã€ã¯ãã¢ã¬ã€è§£æ ãå®
æœ ãã(12,14).
ãã®çµæ, 23çš® ã®æ©èœæªç¥ã§ããäºæåå¶åŸ¡ç³»å¿çå¶
埡è çœè³ªã®æšçéºäŒååè£(14)ã®äžã«ã¯, ã㪠ãã®æ©èœæ¢
ç¥éºäŒåãå« ãŸããŠãã. äŸ ãæãããš, YdbG-YdbF
ç³»ã®æšçéºäŒååè£ã¯èµ°åæ§ã«é¢äžããéºäŒå矀ãå«ã
ã§ãã, ãã®ç³»ãèµ°åæ§ ã«é¢é£ ããŠãããšäºæ³ããã.
ãŸã YvrG-YvrH ã®æšçéºäŒå矀 ã«ã¯, 现èå£ ããã
ã¯çŽ°èèæ©èœ ãšé¢ä¿ ããŠãããšæãããéºäŒå矀ãå€ ã
å«ãã§ãã. ãã®ãããªäºæåå¶åŸ¡ç³»ã®æšçéºäŒåæ å ±
ã¯, ä»åŸã®æ©èœæ¢ç¥ã®äºæåå¶åŸ¡ç³»ã®è§£æãããã«é²å±
ãã ãã®ã¿ãªãã, æ©èœæªç¥ã®äºæåå¶åŸ¡ç³»ã®è§£æã«ã
倧ãã«å¯äžãããã®ãšæããã.
è€æ°ã®äºæåå¶åŸ¡ç³» (DesK-DesR ãš YvfT-YvfU, ã
ãã³ YvqE-YvqC ãš YxjM-YxjL ãš YhcY-YhcZ) ã®
æšçéºäŒååè£éã«é¡èãªéè€ãã¿ããã(14). å³3ã«,
ãããã®éè€ ãšããã瀺åããäºæåå¶åŸ¡ç³»éã®çžäºäœ
çš ã瀺 ãã. èå³æ·± ã ããšã«, YxjL ãš YvqC ã ãã³
DesR ãš YvfU ã¯äºãã«é¡èãªçžåæ§ ã瀺ã. ãã®ããš
ã ã, äºãã«æšçéºäŒåãéè€ããäºæåå¶åŸ¡ç³»ã¯, ã
ã®é²åéçšã§æ¯èŒçæè¿ ã«åå ããã®ã§ã¯ãªãã ãšäºæ³
㧠ã, ãã€ã©ã®ããã«ã㊠ãã ãã®äºæåå¶åŸ¡ç³»ãæ ã
ç«ã£ããã«ã€ããŠã®ç 究ãåŸ ããã.
2) çªçŽ 代è¬ã®DNAã ã€ã¯ãã¢ã¬ã€è§£æ
æ¯èèãå«ãå€ ãã®çŽ°è ã¯ã¢ã³ã¢ãã¢ãçªçŽ æº ãšããŠ
å³2 â ÎdegS ã® ããšã§ã® aprE ã® degU åŒ·å¶ çº çŸ ã«äŒŽ ãèªå° çºçŸ(12)
aprE éºäŒå 㯠DegU ã®æšçéºäŒåã®äžã€ã§ãã. ãã® aprE éºäŒå ã lacZ éºäŒå ãšèå ããã ãš, β-ã¬ã©ã¯ ãã·ããŒãŒ (β-Gal) æŽ»æ§ ã
枬å®ã ãããšã«ã ã aprE éºäŒåã®çºçŸ ã远跡 ããããšã㧠ãã. ãµ ã³ã ãªã³ã°æéã®T0㯠å¢æ®çµäºæéãè¡šãã.
548 ååŠãšçç© Vol. 40, No. 8, 2002
å©çšããã, ã¢ããé žãªã©çš®ã ã®å«çªçŽ ååç©ã®çªçŽ ã
ãå©çšãã. ãã ãçš®ã ã®çªçŽ æºã®äžã§, æ¯èèãæ ã
å¹çããå©çšã§ããã®ãã°ã«ã¿ ãã³ã§ãã. ããã«å¯Ÿ ã
ãŠ, ã°ã«ã¿ãã³é žãå¯äžã®çªçŽ æº ãšããå Žåã¯å¢æ®ãé
ã㪠ã, 现è ãçªçŽ å¶éç¶æ ã«çœ® ãããšãã§ãã. ãã®
äžéã«äœçœ®ããã®ãã¢ã³ã¢ãã¢ã§ãã. ãããŠ, 现èã«
ãšã£ãŠæ ãçªçŽ ã®äŸçµŠãæºããããæ¡ä»¶ ãšèããããã®
ã¯, ã°ã«ã¿ãã³ãšã¢ããé žã®æ··åç©ãåæã«äŸçµŠ ããç¶
æ ã§, å¢æ®é床ãæ ãéã. ãã®çªçŽ ä»£è¬ ãå¶åŸ¡ ããŠã
ãå¶åŸ¡èçœè³ª ã¯, ã°ã«ã¿ ãã³åæé µçŽ ã§ãã GlnA ãš3
çš®ã®HTHè çœè³ª (TnrA, GlnR ã ãã³ CodY) ã§ãã.
æ¯èèã®çªçŽ 代è¬ã®å¶åŸ¡æ©æ§ã«ã€ããŠã¯è§£æãããŠããª
ããšãããå€ãã, GlnA ã现è ã®çªçŽ ã®äŸçµŠåºŠãæç¥
ã, ãã®æ å ±ã TnrA ã GlnR ã«äŒ ãããšèããããŠã
ã.
ãã®è€éãªçªçŽ 代è¬ã®å¶åŸ¡ç³»ãæããã«ããããã«,
éçæ ª ãšå¶åŸ¡èçœè³ªéºäŒåã®å€ç°æ ª ãçš ããŠ, çš®ã ã®
çªçŽ äŸçµŠç¶æ ã§DNAã ã€ã¯ãã¢ã¬ã€è§£æãè¡ ãªã£ã.
詳现 ã¯èªé¢ã®éœåã§ç ãã, ãããã®è§£æã®çµææãã
ã«ãªã£ãç¥èŠã¯æ¬¡ã®é ãã§ãã. (1)æ¯èèã®çªçŽ 代è¬å¶
埡ã«ã¯, GlnA ã«äŸåããå¶åŸ¡ç³» ãšäŸå ããªãå¶åŸ¡ç³»ã
ãã. (2) GlnA ã«äŸåããå¶åŸ¡ç³» ãäŸå ããªãç³»ã«ã,
TnrA, GlnR ãš CodY ã«ããå¶åŸ¡éã«å¯æ¥ãªé¢é£ãã
ã, æè¿æ ããã«ãªã£ã GlnA ãš TnrA ã®çžäºäœçšã®ã
ããªè çœè³ªéçžäºäœçš ã瀺åã ãç¥èŠãåŸ ããã. (3)
TnrA ã¯çªçŽ å¶éç¶æ ã§, GlnR ãš CodY ã¯çªçŽ ãåå
ããç¶æ ã§å ããšèããããŠããã, ãã®å¹é€æ¡ä»¶ã§ã®
ã¿æ©èœããã®ã§ã¯ãªã, ä»ã®å¹é€æ¡ä»¶ã§ ãå ãæªç¥ã®æ©
èœããã£ãŠãã.
ä»åŸ, ãã ãDNAã ã€ã¯ãã¢ã¬ã€è§£æã®çµæãåº ã«,
æ¯èèã®çªçŽ 代è¬ã®å šè²ã«è¿« ããã.
3. DNAã ã€ã¯ã㢠ã¬ã€è§£æ ããŒã¿ã®å ¬é ãšè¡šç€ºæ³ã®
éçº
çŸåš ãŸã§ã«, 200ã ãŸãã®æ¯èèã®DNAã ã€ã¯ãã¢
ã¬ã€è§£æã®ããŒã¿ãèç© ãã, ããã«ãã®æ°ãå¢ ãã€
ã€ãã. ãã ãã®ãã¡è«æ ãšããŠå ¬è¡š ããã ãã®ã«é¢ã
㊠ã¯, http://www.genome.ad.jp/kegg/expression/ã§
å ¬è¡š ããŠãã. ãã®ä»ã®ããŒã¿ ãé æ¬¡å ¬é ããŠã ãäº
å®ã§ ãã. ãŸã, ãã§ã«è»¢åå¶åŸ¡å åã®ã㌠ã¿ããŒã¹
å³3 â ã 〠㯠ã㢠ã¬ã€è§£æ 㧠æ ãã ã«ãª ã£ãäºæ å å¶åŸ¡ ç³» éã®çž äºäœ çš(14)
DesK-DesR ãš YvfT-YvfU ã®åã ã®æšçéºäŒååè£ ãš YvqE-YvqC, YxjM-YxjL, YhcY-YhcZ ã®åã ã®æšçéºäŒååè£ ã«é¡è ãªéè€
(é㪠ãå ã£ãŠããåå ã®æ°å ã¯éè€æ°) ãã¿ ããã. åè ã®éè€ ã¯, DesK-DesR ãš YvfT-YvfU ç³»ã®æš çéºäŒå矀 ã®äžã« yvfU éºäŒåã
å« ãŸã ãããšã§èª¬æ㧠ãã. ãŸãåŸè ã®éè€ ã¯, YxjM-YxjL ç³»ã®æšçéºäŒå矀 ã«ã¯å¿çå¶åŸ¡è çœè³ªéºäŒå (yvqC ãš yhcZ) ã, YvqE-
YvqC ç³»ã®æšçéºäŒå矀 ã«ã yxjL ãš yhcZ ãå« ãŸã ãããšãã説æã§ãã. ä»¥äž ã®éè€ã ã, ç¢å°ã§ç€ºãäºæåå¶åŸ¡ç³»ã®çžäºäœçšã瀺å ã
ãã.
ååŠãšçç© Vol. 40, No. 8, 2002 549
(DBTBS, http://elmo.ims.u-tokyo.ac.jp/dbtbs/) ã å ¬
é ã㊠ã ã(15).
DNAã 〠㯠ã㢠㬠〠解 æ ã® èš å€§ 㪠ã ㌠㿠ã ç 確 ã«è¡š
瀺 ã ã ã ãš ãå¿ èŠ ãš ãª ã£ ãŠ ãã. ã ãã§, å³4㫠瀺 ã ã€
ã³ ã ã ã¯W&G瀟 ãšæ¯ è è ã®DNAã 〠㯠ã 㢠㬠〠ã
㌠㿠ã®è¡š 瀺 㜠ã ã (æ¯è è WebGen-Net) ãé çº ãã.
å³ ã« ã¯, DNAã 〠㯠ã 㢠㬠〠解 æ ã« ã ãæœ åº ã§ ã ã
DegU 㬠㮠㥠ã ã³ ã® æ§ æ éº äŒ å å è£ ã ç¢ å° ã§ ç€º ã ㊠ã
ã. å® é 㯠DegU ã« ã ãæ£ ãšè² ã® å¶ åŸ¡ ãã« ã© ãŒ ã® ç¢ å° ã§
åº å¥ ã㊠ã ã. éº äŒ å 㮠蟌 ã¿å ¥ 㣠ãå æ ã 㪠ã ã ã³ ã ãª
ã㊠ã ã, ã 㮠㪠ã ã ã³ ã DegU ã§ å¶ åŸ¡ ãã ㊠ã ã ã ãš
ã瀺 ã㊠ã ã.
æ¯èèã®ã¡ã¿ãããŒã 解æ
ã¡ã¿ãããŒã ãšã¯, ããå¹ é€æ¡ä»¶ã®çŽ°è å 代è¬ç£ç©
(metabolite) ã®ç·äœãè¡šãã. 现èå ã§éºäŒåçºçŸå¶åŸ¡
ãã²ãèµ· ããèŠå ã¯, çš®ã ã®äœååååç©ã®æ¿åºŠã®å€å
ãšè ãããã. ãããã£ãŠ, ã¡ã¿ãããŒã ã ãã©ã³ã¹ã¯
ãªã ããŒã ããã«ã¯ããããªãŒã ãèŠå® ããŠãã ãšãã
ããã. è¿å¹Žã®åææ©åšã®çºå±ã«ãã, 现èã ãè¿ éã«
æœåºããå€ ãã®ä»£è¬ç£ç©ã®æ··åç© ã, åã ã«ã€ããŠçµç¹
çã«å®é ããŠã ãããšãå¯èœ ãšãªã£ãŠ ããŠãã.
京éœå€§åŠã®è¥¿å²¡ç 究宀ã§ã¯, äžç ã«å é§ ããŠæ¯èèã®
ã¡ã¿ãããŒã 解æã粟åçã«é²ããããŠãã. æ¯èè现
è ãã¡ã¿ããŒã«ãè»é žã«æµžæœ€ ã, 代è¬ç£ç© ãæœåºãã.
å³4 â æ¯ èè ã®è»¢ åå¶ åŸ¡ 衚瀺 ã ãŒã« (æ¯èè WebGen-Net) ã«ã ã衚瀺äŸ
æ¯èè WebGen-Net ã¯, ã€ã³ã ãã¯W&G瀟 ã®åç°çŸå¯žå€«æ° ãšå ±åã§éçº ããã ãã®ã§ã ã. æ¯èèã®å šèçœè³ªéºäŒå4,100å ãã²ãã
ã®+é ã«ããéºäŒå矀ãå€åŽ ã«, -é ã«ããéºäŒåãå åŽ ã«, ã²ãã äž ã®äœçœ®ã«åŸ ãå圢 ã«é 眮ãã. DNAè€ è£œã®æ¹å ãšéºäŒå転åã®æ¹å
ãäžèŽã ãåŸ åã ããã®ã§, éºäŒåé 眮 ã«ã¯å³ã®ãããªå ããã§ãã. çŸåš, ãã®è¡šç€º ããŒã«ã«ã¯, DNAã ã€ã¯ãã¢ã¬ã€è§£æ ã§åŸ ããã50
匱ã®å¶åŸ¡èçœè³ª ã®ã¬ã®ã¥ãã³æ§æéºäŒååè£ ãš, 30è¿ ãã®çš®ã ã®å¹é€æ¡ä»¶ ã§å€åã ãéºäŒå矀ãå ã蟌 ãŸããŠãã. ãŸã, ãã® ããŒã«ã§ã¯
éºäŒåãã² ãã äžã®äœçœ®ã§ãœãŒ ãããã ãšã«ãã, åéºäŒåã ã©ã®å¶åŸ¡äžã«ããã ãäžèŠ§è¡š ãšããŠç€ºã ããšã㧠ã, ãªããã³ãæ§æããéº
äŒå矀ãé¡æšããããšãå¯èœã§ã ã. å³äžæå ãã¯ãããã8〠ã®éºäŒå ã¯, DegU ã®æ£ã®å¶åŸ¡äž ã«ããããšãå®éšçã«èšŒ æãããŠã ã.
550 ååŠãšçç© Vol. 40, No. 8, 2002
æœ åºæ¶² ã ã 㣠ã ã© ãªãŒé» æ° æ³³ å ã« ã ã, 代 è¬ ç£ ç© ã å é¢
ã質 é å æ èš ã« ã ã ãŠ, å ã ã®ä»£ è¬ ç£ ç© ã å æ ã ã. çŸ
åš, 㢠ããé ž, æ æ© é ž 㪠ã©, ã 㪠ã㮠代 è¬ ç£ ç© ã®å® é ã
å¯ èœ ãšãª 㣠㊠ã㊠ã ã. å° æ¥ ã¯, ã¡ ã¿ ã ã ㌠ã 解 æ çµ æ
ãš ãã© ã³ã¹ 㯠ãªã ã㌠ã ã ã ã 㯠ã ã ã 㪠㌠ã 解 æ çµ æ
ãšãçµ± å ãã ã ã ãšã« ã ã, äœ å å å å ç© ãä» ãã ç ã®
éº äŒ å çº çŸ å¶ åŸ¡ ã ã ã㯠㌠㯠ãæ§ ç¯ ã ã ã ãšã å¯ èœ ã« ãª
ã ã ã ã.
æ¥æ¬ã®æ¯èè ã²ãã 解æã ãã³ãã®ãã¹ ãã²ãã ã·ãŒã±ã³ã¹è§£æ
ãé ããŠ, å¥è¯å 端倧 ã®å°ç¬ åçŽæ¯ ææ ãäž»å° çåœ¹å² ãæ ã£ãŠ ã
ã. æ¬çš¿ ã«çŽ¹ä» ãã æ¥æ¬ ã®ãã¹ ãã²ãã ã·ãŒã± ã³ã¹è§£æ ã¯, å°ç¬
å, ç波倧 ã®å±±æ ¹åç·, ä¿¡å·å€§ã®é¢å£é äž, åŒç倧 ã®å®å®¶çŸ©äºº, æ±
海倧ã®ç°äžæ倫, æ±äº¬èŸ²å·¥å€§ã®ç«¹ å éé ãšäœè€ å, ç«æ倧ã®æ²³æ
å¯å£«å€«, æ±äº¬èŸ²å€§ã®åå·åæ, æå倧ã®æž¡éšäžä», ææ倧ã®å€§æšç²
å, å®®åŽ å»å€§ ã®äžå±±å»ºç· ã®åå ç ãšçè ã ãªãŒã㌠ãšããç 究ã°
ã«ãŒãã®å ±åç 究ã§ãã.
æ ç®
1) F. Kunst, N. Ogasawara et al.: Nature, 390, 249 (1997).
2) å°ç¬ åçŽæ¯ : èçœè³ª æ žé ž é µçŽ , 42, 2933 (1997).
3) è€ ç°æ³°å€ªé: ååŠ ãšçç©, 36, 106 (1998).
4) å°ç¬ åçŽæ¯ : è çœè³ª æ žé ž é µçŽ , 44, 1512 (1999).
5) å°ç¬ åçŽæ¯ : çŸä»£å»ç, 32, 165 (2000).
6) K. Yoshida, I. Ishio, E. Nagakawa, Y. Yamamoto, M.Yamamoto & Y. Fujita: Microbiology, 146, 573 (2000).
7) N. Ogasawara: Res. Microbiol., 151, 129 (2000).8) å°ç¬ åçŽæ¯ : è çœè³ª æ žé ž é µçŽ , 46, 2379 (2001).
9) äžå±±å»ºç·, é«æŸå®æ²», æž¡éšäžä», å±±æ ¹ åç·, 竹 å éé, æ äº
èš, ç¬ å康è£, å°æå倫, å°ç¬ åçŽæ¯ :â å®éšå»åŠå¥åâ, çŸå
瀟, 2000, p.221.
10) è€ç°æ³°å€ªé:âã² ãã æ©èœ, çºçŸãããã¡ã€ã« ãšãã©ã³ã¹ã¯ ãª
ã ããŒã â, äžå±±æžåº, 2000, p.40.
11) K. Yoshida, K. Kobayashi, Y. Miwa, C. Kang, M.Matsunaga, H. Yamaguchi, S. Tojo, M. Yamamoto, R.Nishi, N. Ogasawara, T. Nakayama & Y. Fujita: NucleicAcids Res., 29, 683 (2001).
12) M. Ogura, H. Yamaguchi, K. Yoshida, Y. Fujita & T.Tanaka: Nucleic Acids Res., 29, 3804 (2001).
13) å±±å£åŒæ¯ , æ±æ¢ç¹é, è€ ç°æ³°å€ªé: ååŠ ãšçç©, 40, 2 (2002).
14) K. Kobayashi, M. Ogura, H. Yamaguchi, K. Yoshida, N.Ogasawara, T. Tanaka & Y. Fujita: J. Bacteriol., 183,7365 (2001).
15) T. Ishii, K. Yoshida, G. Terai, Y. Fujita & K. Nakai:Nucleic Acids Res., 29, 278 (2001).
ååŠ ãšçç© Vol. 40, No. 8, 2002 551