CELL MOTILITY IS REQUIRED FOR THE TRANSMISSION OF C-FACTOR, AN INTERCELLULAR SIGNAL THAT COORDINATES FRUITING BODY MORPHOGENESIS OF MYXOCOCCUS-XANTHUS
CELL MOTILITY IS REQUIRED FOR THE TRANSMISSION OF C-FACTOR, AN INTERCELLULAR SIGNAL THAT COORDINATES FRUITING BODY MORPHOGENESIS OF MYXOCOCCUS-XANTHUS
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DOI：
10.1101/gad.4.6.896
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发表时间：
1990-06-01
影响因子：
10.5
通讯作者：
KAISER, D
中科院分区：
文献类型：
--
作者：
KIM, SK;KAISER, D
两种不同的突变类粘膜球菌的发育表型之间存在惊人的相似性。在所有测试的条件下，一类MGLA突变体是非运动的。第二类CSGA突变体是机动性的，但属于一类信号缺陷的发育突变体，这些突变体不能单独发展，但会与完整的野生型细胞混合时会发展。然而，CSGA和MGLA突变体均无法正确汇总或在诱导形成成果体时孢子。 MGLA突变和CSGA突变以相同的方式影响一群与发育基因的LACZ融合体的表达，这表明非运动细胞和CSGA细胞在相似阶段停止发育。这些突变体之间发育表型相似性的一种解释是，CSGA介导细胞相互作用需要运动。为了支持这一假设，我们报告说，C-因子是一种基于新生野生型果实物体纯化的蛋白MGLA菌株中的融合，显然没有恢复其运动能力。野生型活性C因子水平可以从MGLA细胞中纯化，但是完整的MGLA细胞在细胞 - 细胞混合时不会挽救CSGA细胞。完整的野生型细胞无法恢复MGLA突变体的孢子形成和β-半乳糖苷酶的表达。这些结果支持以下假设：开发过程中细胞之间的C因子传播需要供体和响应者细胞运动。我们建议，适当的细胞间C因子传播可能需要仅在细胞进入刚开始的较密集的，对齐的新生水果体的密集组织后才能实现的细胞。
There are striking similarities between the developmental phenotypes of two different mutant classes of Myxococcus xanthus. The first class, mglA mutants, are nonmotile under all conditions tested. The second class, csgA mutants, are motile but belong to a class of signal-defective developmental mutants that cannot develop alone but will develop when mixed with intact wild-type cells. Nevertheless, both csgA and mglA mutants fail to aggregate properly or to sporulate when induced to form fruiting bodies. An mglA mutation and a csgA mutation affect expression of a panel of lacZ fusions to developmental genes in the same way, indicating that nonmotile cells and csgA cells arrest development at a similar stage. One explanation for the similarity of developmental phenotypes between these mutants is that motility is required for the csgA-mediation cell interaction. In support of this hypothesis, we report that C-factor, a protein purified from nascent wild-type fruiting bodies based on its ability to rescue csgA mutant fruiting body development, also rescues sporulation and expression of .beta.-galactosidase from developmentally controlled lacZ fusion in mglA strains, apparently without restoring their motility. Wild-type levels of active C-factor can be purified from mglA cells, yet intact mglA cells do not rescue csgA cells upon cell-cell mixing. Intact wild-type cells are unable to restore the sporulation and .beta.-galactosidase expression of mglA mutants. These results support the hypothesis that donor and responder cell motility is required for C-factor transmission between cells during development. We propose that proper intercellular C-factor transmission may require a critical spatial orientation of cells achieved only after cells move into the dense, aligned organization of a nascent fruiting body.