Axonemal doublet microtubules can split into two complete singlets in human sperm flagellum tips

FEBS Letters

article

Davide Zabeo¹  Jacob T. Croft¹  Johanna L. Höög¹ 

[1] Department of Chemistry and Molecular Biology, University of Gothenburg

关键词: axoneme;    cilia;    cryo-electron microscopy;    cryo-electron tomography;    fibrous sheath;    singlet region;   

DOI  :  10.1002/1873-3468.13379

来源: John Wiley & Sons Ltd.

【 摘 要 】

Convergent promoters exert transcriptional interference (TI) by several mechanisms including promoter occlusion, where elongating RNA polymerases (RNAPs) block access to a promoter. Here, we tested whether pausing of RNAPs by obstructive DNA-bound proteins can enhance TI by promoter occlusion. Using the Lac repressor as a ‘roadblock’ to induce pausing over a target promoter, we found only a small increase in TI, with mathematical modelling suggesting that rapid termination of the stalled RNAP was limiting the occlusion effect. As predicted, the roadblock-enhanced occlusion was significantly increased in the absence of the Mfd terminator protein. Thus, protein roadblocking of RNAP may cause pause-enhanced occlusion throughout genomes, and the removal of stalled RNAP may be needed to minimize unwanted TI.

【 授权许可】

Unknown