| ²é¿´: 136 | »Ø¸´: 4 | |||
| µ±Ç°Ö÷ÌâÒѾ´æµµ¡£ | |||
| ¡¾ÐüÉͽð±Ò¡¿»Ø´ð±¾ÌûÎÊÌ⣬×÷Õßacnotlove½«ÔùËÍÄú 20 ¸ö½ð±Ò | |||
[ÇóÖú]
ÇóÖú·Òë¡«¡«¡«¡«ºÜ¼±¡¤¡«¡«¡«ÔÚÏßµÈ ×Ô¼º¸ã¶¨ÁË~~~
|
|||
|
HD-ZIPIII and ETT/ARF family genes encode transcriptional regulators and are negatively regulated by the small RNAs miR166 and tasiR-ARF, respectively. The SHL/SHO pathway affects the regulation of these genes simultaneously, which suggests that there is a link between miR166-mediated regulation of HD-ZIPIII and tasiR-ARF-mediated regulation of ETT/ARF. One possibility is that HD-ZIPIII and ETT/ARF genes have opposing functions. Whereas HD-ZIPIII genes promote SAM formation and adaxial leaf fates, ETT/ARF genes suppress them,and their corresponding small RNAs regulate the balance between these two factors to maintain the domains marked by the expression of HD-ZIPIII and miR166 in a bistable manner. In this model, defects in ETT/ARF-tasiR-ARF regulation that lead to overaccumulation of ETT/ARF gene products, as in shl/sho mutants, promote the accumulation of miR166 by suppressing SAM formation and adaxial leaf fate. It is also possible that a defect in the production of an unknown ta-siRNA, directed at the precursors of miR166, resulted in increased the stability of the precursors and overaccumulation of miR166. In summary, we demonstrated that a set of RNAi-related components, whose counterparts in Arabidopsis are involved in ta-siRNA production, is required for the initiation of the SAM, a group of stem cells in plants, during rice embryogenesis. Complete loss of ta-siRNA does not affect SAM initiation in Arabidopsis, which suggests that this mechanism of regulation of stem cell establishment does not operate in Arabidopsis (25, 27). Small RNAs are often conserved between species and mediate fundamental developmental processes by regulating the expression of key regulatory molecules in both plants and animals. The establishment of stem cells is fundamental to all plants, and therefore the regulators of this process, such as transcriptional regulators or signaling molecules, are also likely to be conserved. Our analysis of rice shl/sho mutants revealed that miR166- mediated regulation of HD-ZIPIII expression is sensitive to the ta-siRNA production pathway during SAM formation in rice embryogenesis. Thus, the small RNA pathway enables the unique regulation even on the fundamental process in development, the stem cell establishment, in different species. [ Last edited by acnotlove on 2007-12-6 at 20:24 ] |
» ²ÂÄãϲ»¶
323Çóµ÷¼Á
ÒѾÓÐ6È˻ظ´
Ò»Ö¾Ô¸±±¾©»¯¹¤´óѧ 070300 ѧ˶ 336·Ö Çóµ÷¼Á
ÒѾÓÐ4È˻ظ´
352Çóµ÷¼Á
ÒѾÓÐ3È˻ظ´
Ò»Ö¾Ô¸¶«»ª´óѧ»¯Ñ§070300£¬Çóµ÷¼Á
ÒѾÓÐ8È˻ظ´
277²ÄÁÏ¿ÆÑ§Ó빤³Ì080500Çóµ÷¼Á
ÒѾÓÐ7È˻ظ´
317Çóµ÷¼Á
ÒѾÓÐ18È˻ظ´
293Çóµ÷¼Á
ÒѾÓÐ5È˻ظ´
280·ÖÇóµ÷¼Á Ò»Ö¾Ô¸085802
ÒѾÓÐ7È˻ظ´
0854µç×ÓÐÅÏ¢Çóµ÷¼Á
ÒѾÓÐ3È˻ظ´
263Çóµ÷¼Á
ÒѾÓÐ4È˻ظ´
ͯÐÄ111
½ð³æ (Ö°Òµ×÷¼Ò)
Сľ³æ¿ìÀÖ¾«Áé
- ²©Ñ§EPI: 1
- Ó¦Öú: 97 (³õÖÐÉú)
- ¹ó±ö: 0.025
- ½ð±Ò: 1413.2
- É¢½ð: 3833
- ºì»¨: 61
- Ìû×Ó: 4837
- ÔÚÏß: 470.1Сʱ
- ³æºÅ: 279649
- ×¢²á: 2006-09-16
- ÐÔ±ð: MM
- רҵ: ÑùƷǰ´¦Àí·½·¨Óë¼¼Êõ

2Â¥2007-12-04 14:02:13
wangchen2004
Ìú¸Ëľ³æ (ÕýʽдÊÖ)
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 14788.4
- Ìû×Ó: 695
- ÔÚÏß: 168.9Сʱ
- ³æºÅ: 190135
- ×¢²á: 2006-02-19
- רҵ: Ò©Îïѧ
3Â¥2007-12-04 15:46:25
wjhinsect
½ð³æ (СÓÐÃûÆø)
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 737.5
- Ìû×Ó: 99
- ÔÚÏß: 12.6Сʱ
- ³æºÅ: 459731
- ×¢²á: 2007-11-14
- ÐÔ±ð: GG
|
¸ßÇåZipiiiºÍÔËËÍÐèʱ/¶«Ã˵ØÇøÂÛ̳¼Ò×å»ùÒò±àÂëת¼ ¼à¹ÜÈËÔ±Ó븺µ÷½Ú£¬ÓÉСRNAs miR166ºÍtasiR -¶«Ã˵ØÇøÂÛ̳µÈ¡£¸ÃShl /֣˶ͨ· Ó°Ïìµ÷½ÚÕâЩ»ùÒòµÄͬʱ£¬ ÏÔʾ³öÓÐÁ¬½ÓmiR166½éµ¼µÄµ÷¿Ø ¸ßÇåzipiiiºÍtasiR -¶«Ã˵ØÇøÂÛ̳½éµ¼µÄµ÷¿ØÔËËÍÐèʱ/¶«Ã˵ØÇøÂÛ̳¡£ Ò»ÖÖ¿ÉÄÜÐÔÊÇ£¬¸ßÇåZipiiiºÍÔËËÍÐèʱ/¶«Ã˵ØÇøÂÛ̳»ùÒò ·´¶ÔµÄÖ°ÄÜ¡£¶ø¸ßÇåZipiii»ùÒò´Ù½øÈøÄ· ÐγÉÓë½üÖáÃæÒ¶µÄÃüÔË£¬ÔËËÍÐèʱ/¶«Ã˵ØÇøÂÛ̳»ùÒòÕòѹ£¬ÆäÏàÓ¦µÄСRNAs¹æ·¶Ö®¼äµÄƽºâ ÕâÁ½¸öÒòËØ£¬ÒÔά³ÖÓòÃû£¬±êÖ¾×ÅÓÉ ±í´ï¸ßÇåZipiiiºÍmiR166ÔÚË«ÎÈ̬µÄ·½Ê½¡£ÔÚ ÕâÖÖģʽµÄ±×¶ËÔËËÍÐèʱ/¶«Ã˵ØÇøÂÛ̳- tasiR¶«Ã˵ØÇøÂÛ̳µ÷¿Øµ¼Ö ÒÔoveraccumulationµÄÔËËÍÐèʱ/¶«Ã˵ØÇøÂÛ̳»ùÒò²úÎÒòΪÔÚShl /֣˶ Í»±äÌ壬´Ù½ø»ýÀÛmiR166ÊÜ´òѹ ÈøÄ·µÄÐγÉÓë½üÖáÃæÒ¶µÄÃüÔË¡£ËüÒ²¿ÉÄÜ»áÓРȱËð£¬Éú²úÒ»ÖÖδ֪µÄ´ó°²ÉÁÖС·Ö×Ó¸ÉÈźËÌǺËËᣬÕë¶Ô ÏÈÇýÃÇmiR166 £¬Ôì³É¸ü¶àµÄÎȶ¨ ǰÌåºÍ³¬¹ý»ýÀÛµÄmiR166 ¡£ ×ÜÖ®£¬ÎÒÃÇÖ¤Ã÷ÁËÒ»Ì׺ËÌǺËËá¸ÉÈÅÓÐ¹Ø ²¿¼þ£¬Æä¶ÔÓ¦ÄâÄϽæ²ÎÓë ÕÅ´óǧµÄС·Ö×Ó¸ÉÈźËÌǺËËáÉú²ú£¬ÊÇÐèÒªÆô¶¯µÄÈí¼þ×ʲú¹ÜÀí£¬ Ò»×é¸Éϸ°ûÖ²ÎÔÚË®µ¾Ï¸°ûÅßÌ¥·¢Éú¡£ Íêȫɥʧ°²ÉÁÖС·Ö×Ó¸ÉÈźËÌǺËËá²¢²»Ó°ÏìÈøÄ·Æð±¬ ÄâÄϽæÖУ¬Õâ±íÃ÷£¬ÕâһлúÖÆµÄµ÷½Ú ¸Éϸ°ûµÄ½¨Á¢£¬²¢²»ÔÚÄâÄϽ棨 25 £¬ 27 £© ¡£ СrnaÍùÍùÊDZ£ÊصÄÎïÖÖÖ®¼äºÍµ÷Í£ »ù±¾µÄ·¢Õ¹½ø³ÌÖÐËù¹æ·¶µÄ±í´ï ¹Ø¼üµ÷¿Ø·Ö×ÓÔÚË«·½µÄÖ²ÎïºÍ¶¯Îï¡£¸Ã ½¨Á¢¸Éϸ°ûÊÇ»ù±¾µÄËùÓÐÖ²Î²¢ Òò´Ë£¬¼à¹Ü»ú¹¹µÄÕâ¸ö¹ý³ÌÖУ¬Èçת¼ ¼à¹Ü»ú¹¹»òÐźŷÖ×Ó£¬Ò²¿ÉÄܵõ½±£»¤¡£ ¸ù¾ÝÎÒÃǵķÖÎö£¬Ë®µ¾Shl /֣˶ͻ±äÌåÏÔʾmiR166 - µ¼µÄµ÷¿Ø¸ßÇåZipiii±í´ïµÄÊÇ£¬Ãô¸ÐµØÈÏʶµ½ ÕÅ´óǧµÄС·Ö×Ó¸ÉÈźËÌǺËËáµÄÉú²ú;¾¶ÔÚɽķÐγÉË®µ¾ ÅßÌ¥·¢Óý¡£Òò´Ë£¬Ð¡ºËÌǺËËáͨ·£¬Ê¹ ¶ÀÌØµÄµ÷½Ú£¬ÉõÖÁ¶Ô»ù±¾¹ý³ÌµÄ·¢Õ¹£¬ ¸Éϸ°ûµÄ½¨Á¢£¬ÔÚ²»Í¬µÄÎïÖÖ¡£ |

4Â¥2007-12-04 16:01:14
wjhinsect
½ð³æ (СÓÐÃûÆø)
- Ó¦Öú: 0 (Ó×¶ùÔ°)
- ½ð±Ò: 737.5
- Ìû×Ó: 99
- ÔÚÏß: 12.6Сʱ
- ³æºÅ: 459731
- ×¢²á: 2007-11-14
- ÐÔ±ð: GG

5Â¥2007-12-04 16:09:57













»Ø¸´´ËÂ¥