title: Septin ring assembly is regulated by Spt20, a structural subunit of the SAGA complex.
abstract: Accurate cell division requires the proper assembly of high-order septin structures. In fission yeast (Schizosaccharomyces pombe), Spn1-Spn4 are assembled into a primary septin ring at the division site, and the subsequent recruitment of Mid2 to the structure results in a stable septin ring. However, not much is known about the regulation of this key process. Here, we found that deletion of Spt20, a structural subunit of the Spt-Ada-Gcn5-acetyltransferase (SAGA) transcriptional activation complex, caused a severe cell separation defect. The defect was mainly due to impaired septin ring assembly, as 80% of spt20Δ cells lost septin rings at the division sites. Spt20 regulates septin ring assembly partially through the transcriptional activation of mid2(+). Spt20 also interacted with Spn2 and Mid2 in vitro and was associated with other components of the ring in vivo. Spt20 colocalized with the septin ring, but did not separate when the septin ring split. Importantly, Spt20 regulated the stability of the septin ring and was required for the recruitment of Mid2. The transcription-dependent and -independent roles of Spt20 in septin ring assembly highlight a multifaceted regulation of one process by a SAGA subunit.
authors.affiliation: State Key Laboratory of Genetic Engineering, School of Life Sciences, and Institute of Biomedical Sciences, Shanghai 200433, China.
authors.forename: Bingkun
authors.initials: B
authors.lastname: Lei
authors.affiliation: State Key Laboratory of Genetic Engineering, School of Life Sciences, and Institute of Biomedical Sciences, Shanghai 200433, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Genetic Engineering, School of Life Sciences, and Institute of Biomedical Sciences, Shanghai 200433, China.
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China.
authors.forename: Yan-Wen
authors.initials: YW
authors.lastname: Tan
authors.affiliation: State Key Laboratory of Genetic Engineering, School of Life Sciences, and Institute of Biomedical Sciences, Shanghai 200433, China Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai 200433, China yaoyu@fudan.edu.cn honglu0211@yahoo.com.
authors.forename: Yao
authors.initials: Y
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Genetic Engineering, School of Life Sciences, and Institute of Biomedical Sciences, Shanghai 200433, China Shanghai Engineering Research Center of Industrial Microorganisms, Shanghai 200433, China Shanghai Collaborative Innovation Center for Biomanufacturing Technology, Shanghai 200237, China yaoyu@fudan.edu.cn honglu0211@yahoo.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
mesh_terms: D002455:Cell Division; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D058112:Septins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; C091625:MID2 protein, S cerevisiae; D008562:Membrane Glycoproteins; C507785:SAGA complex, S cerevisiae; C099690:SPT20 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D058112:Septins
keywords: Fission yeast; Mid2; SAGA; Septin; Spt20