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チバ シノブ
CHIBA SHINOBU
千葉 志信 所属 京都産業大学 生命科学部 先端生命科学科 職種 教授 |
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| 言語種別 | 英語 |
| 発行・発表の年月 | 2005/10 |
| 形態種別 | その他 |
| 標題 | Engulfment-regulated proteolysis of SpoIIQ: evidence that dual checkpoints control sigma(K) activity |
| 執筆形態 | その他 |
| 掲載誌名 | MOLECULAR MICROBIOLOGY |
| 出版社・発行元 | BLACKWELL PUBLISHING |
| 巻・号・頁 | 58(1),pp.102-115 |
| 著者・共著者 | Jiang, X,A Rubio,S Chiba,K Pogliano |
| 概要 | During Bacillus subtilis sporulation, the engulfment checkpoint is thought to directly regulate late forespore transcription but to indirectly regulate late mother cell transcription, via the sigma(G)-produced protease SpoIVB. We here demonstrate that SpoIIQ is subject to sigma(G)-independent, but engulfment-dependent, proteolysis that depends on SpoIVB. Thus, SpoIVB produced before engulfment supports some SpoIVB-dependent events, suggesting that its activity or access to substrates must be regulated by engulfment. Furthermore, a mutation (bofA) that allows sigma(K) to be active without sigma(G) does not allow sigma(K) activity in engulfment mutants, although the pro-sigma(K) processing enzyme (SpoIVFB) is localized to the septum in engulfment mutants, suggesting that engulfment comprises a second checkpoint for sigma(K) Finally, we find that SpoIIQ and another protein required for sigma(G) activity (SpoIIIAH), which directly interact and assemble helical structures around the forespore, recruit the sigma(K)-processing enzyme SpoIVFB to the forespore and these structures. We suggest that these foci serve a synapse-like role, allowing engulfment to simultaneously control both sigma(G) and sigma(K), and integrating multiple checkpoints and signalling pathways. |
| DOI | 10.1111/j.1365-2958.2005.04811.x |
| ISSN | 0950-382X |