Genetic and Physical Interactions Between Factors Involved in Both Cell Cycle Progression and Pre-mRNA Splicing inSaccharomyces cerevisiae

AbstractThe PRP17/CDC40 gene of Saccharomyces cerevisiae functions in two different cellular processes: pre-mRNA splicing and cell cycle progression. The Prp17/Cdc40 protein participates in the second step of the splicing reaction and, in addition, prp17/cdc40 mutant cells held at the restrictive temperature arrest in the G2 phase of the cell cycle. Here we describe the identification of nine genes that, when mutated, show synthetic lethality with the prp17/cdc40Δ allele. Six of these encode known splicing factors: Prp8p, Slu7p, Prp16p, Prp22p, Slt11p, and U2 snRNA. The other three, SYF1, SYF2, and SYF3, represent genes also involved in cell cycle progression and in pre-mRNA splicing. Syf1p and Syf3p are highly conserved proteins containing several copies of a repeated motif, which we term RTPR. This newly defined motif is shared by proteins involved in RNA processing and represents a subfamily of the known TPR (tetratricopeptide repeat) motif. Using two-hybrid interaction screens and biochemical analysis, we show that the SYF gene products interact with each other and with four other proteins: Isy1p, Cef1p, Prp22p, and Ntc20p. We discuss the role played by these proteins in splicing and cell cycle progression.

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The Prpl + Gene Required for Pre-mRNA Splicing in Schizosaccharomyces pombe Encodes a Protein That Contains TPR Motifs and Is Similar to Prp6p of Budding Yeast

Genetics ◽

10.1093/genetics/147.1.101 ◽

1997 ◽

Vol 147 (1) ◽

pp. 101-115 ◽

Cited By ~ 5

Author(s):

Seiichi Urushiyama ◽

Tokio Tani ◽

Yasumi Ohshima

Keyword(s):

Cell Cycle ◽

Amino Acid ◽

Schizosaccharomyces Pombe ◽

Protein Interactions ◽

Nuclear Export ◽

Cell Cycle Progression ◽

Synthetic Lethality ◽

Cell Cycle Control ◽

Mrna Splicing ◽

Restrictive Temperature

Abstract The prp (pre-mRNA processing) mutants of the fission yeast Schizosaccharomyces pombe have a defect in pre-mRNA splicing and accumulate mRNA precursors at a restrictive temperature. One of the prp mutants, prp1-4, also has a defect in poly(A)+ RNA transport. The prp1 + gene encodes a protein of 906 amino acid residues that contains 19 repeats of 34 amino acids termed tetratrico peptide repeat (TPR) motifs, which were proposed to mediate protein-protein interactions. The amino acid sequence of Prplp shares 29.6% identity and 50.6% similarity with that of the PRP6 protein of Saccharomyces cerevisiae, which is a component of the U4/U6 snRNP required for spliceosome assembly. No functional complementation was observed between S. pombe prp1 + and S. cerevisiae PRP6. We examined synthetic lethality of prp1-4 with the other known prp mutations in S. pombe. The results suggest that Prp1p interacts either physically or functionally with Prp4p, Prp6p and Prp13p. Interestingly, the prp1 + gene was found to be identical with the zer1 + gene that functions in cell cycle control. These results suggest that Prp1p/Zer1p is either directly or indirectly involved in cell cycle progression and/or poly(A)+ RNA nuclear export, in addition to pre-mRNA splicing.

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Son Is Essential for Nuclear Speckle Organization and Cell Cycle Progression

Molecular Biology of the Cell ◽

10.1091/mbc.e09-02-0126 ◽

2010 ◽

Vol 21 (4) ◽

pp. 650-663 ◽

Cited By ~ 53

Author(s):

Alok Sharma ◽

Hideaki Takata ◽

Kei-ichi Shibahara ◽

Athanasios Bubulya ◽

Paula A. Bubulya

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Mrna Processing ◽

Mrna Splicing ◽

Scaffolding Protein ◽

Splicing Factors ◽

Nuclear Speckles ◽

Intact Cells ◽

Cycle Progression ◽

Processing Factors

Subnuclear organization and spatiotemporal regulation of pre-mRNA processing factors is essential for the production of mature protein-coding mRNAs. We have discovered that a large protein called Son has a novel role in maintaining proper nuclear organization of pre-mRNA processing factors in nuclear speckles. The primary sequence of Son contains a concentrated region of multiple unique tandem repeat motifs that may support a role for Son as a scaffolding protein for RNA processing factors in nuclear speckles. We used RNA interference (RNAi) approaches and high-resolution microscopy techniques to study the functions of Son in the context of intact cells. Although Son precisely colocalizes with pre-mRNA splicing factors in nuclear speckles, its depletion by RNAi leads to cell cycle arrest in metaphase and causes dramatic disorganization of small nuclear ribonuclear protein and serine-arginine rich protein splicing factors during interphase. Here, we propose that Son is essential for appropriate subnuclear organization of pre-mRNA splicing factors and for promoting normal cell cycle progression.

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Regulation of cell cycle drivers by Cullin-RING ubiquitin ligases

Experimental & Molecular Medicine ◽

10.1038/s12276-020-00508-4 ◽

2020 ◽

Vol 52 (10) ◽

pp. 1637-1651 ◽

Cited By ~ 1

Author(s):

Sang-Min Jang ◽

Christophe E. Redon ◽

Bhushan L. Thakur ◽

Meriam K. Bahta ◽

Mirit I. Aladjem

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Cell Cycle Progression ◽

Ubiquitin Ligases ◽

Anaphase Promoting Complex ◽

Cycle Progression ◽

Cellular Processes ◽

Cellular Pathways ◽

Regulation Of Cell Cycle ◽

F Box Protein

Abstract The last decade has revealed new roles for Cullin-RING ubiquitin ligases (CRLs) in a myriad of cellular processes, including cell cycle progression. In addition to CRL1, also named SCF (SKP1-Cullin 1-F box protein), which has been known for decades as an important factor in the regulation of the cell cycle, it is now evident that all eight CRL family members are involved in the intricate cellular pathways driving cell cycle progression. In this review, we summarize the structure of CRLs and their functions in driving the cell cycle. We focus on how CRLs target key proteins for degradation or otherwise alter their functions to control the progression over the various cell cycle phases leading to cell division. We also summarize how CRLs and the anaphase-promoting complex/cyclosome (APC/C) ligase complex closely cooperate to govern efficient cell cycle progression.

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Functional analyses of interacting factors involved in both pre-mRNA splicing and cell cycle progression in Saccharomyces cerevisiae

RNA ◽

10.1017/s1355838200000984 ◽

2000 ◽

Vol 6 (11) ◽

pp. 1565-1572 ◽

Cited By ~ 36

Author(s):

CAROLINE S. RUSSELL ◽

SIGAL BEN-YEHUDA ◽

IAN DIX ◽

MARTIN KUPIEC ◽

JEAN D. BEGGS

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Cycle ◽

Cell Cycle Progression ◽

Mrna Splicing ◽

Cycle Progression ◽

Functional Analyses

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Tyr198 is the Essential Autophosphorylation Site for STK16 Localization and Kinase Activity

International Journal of Molecular Sciences ◽

10.3390/ijms20194852 ◽

2019 ◽

Vol 20 (19) ◽

pp. 4852 ◽

Cited By ~ 1

Author(s):

Junjun Wang ◽

Juanjuan Liu ◽

Xinmiao Ji ◽

Xin Zhang

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Kinase Activity ◽

Kinase Domain ◽

Serine Threonine Kinase ◽

Cycle Progression ◽

Threonine Kinase ◽

Cellular Processes ◽

Activation Segment ◽

And Function

STK16, reported as a Golgi localized serine/threonine kinase, has been shown to participate in multiple cellular processes, including the TGF-β signaling pathway, TGN protein secretion and sorting, as well as cell cycle and Golgi assembly regulation. However, the mechanisms of the regulation of its kinase activity remain underexplored. It was known that STK16 is autophosphorylated at Thr185, Ser197, and Tyr198 of the activation segment in its kinase domain. We found that STK16 localizes to the cell membrane and the Golgi throughout the cell cycle, but mutations in the auto-phosphorylation sites not only alter its subcellular localization but also affect its kinase activity. In particular, the Tyr198 mutation alone significantly reduced the kinase activity of STK16, abolished its Golgi and membrane localization, and affected the cell cycle progression. This study demonstrates that a single site autophosphorylation of STK16 could affect its localization and function, which provides insights into the molecular regulatory mechanism of STK16’s kinase activity.

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Requirement for TAFII250 Acetyltransferase Activity in Cell Cycle Progression

Molecular and Cellular Biology ◽

10.1128/mcb.20.4.1134-1139.2000 ◽

2000 ◽

Vol 20 (4) ◽

pp. 1134-1139 ◽

Cited By ~ 46

Author(s):

Elizabeth L. Dunphy ◽

Theron Johnson ◽

Scott S. Auerbach ◽

Edith H. Wang

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Temperature Sensitive ◽

Cycle Progression ◽

Acetyltransferase Activity ◽

Cycle Arrest ◽

Protein Encoding ◽

Acetyltransferase Domain ◽

Mutant Cells

ABSTRACT The TATA-binding protein (TBP)-associated factor TAFII250 is the largest component of the basal transcription factor IID (TFIID). A missense mutation that maps to the acetyltransferase domain of TAFII250 induces the temperature-sensitive (ts) mutant hamster cell lines ts13 and tsBN462 to arrest in late G1. At the nonpermissive temperature (39.5°C), transcription from only a subset of protein encoding genes, including the G1 cyclins, is dramatically reduced in the mutant cells. Here we demonstrate that the ability of the ts13 allele of TAFII250 to acetylate histones in vitro is temperature sensitive suggesting that this enzymatic activity is compromised at 39.5°C in the mutant cells. Mutagenesis of a putative acetyl coenzyme A binding site produced a TAFII250 protein that displayed significantly reduced histone acetyltransferase activity but retained TBP and TAFII150 binding. Expression of this mutant in ts13 cells was unable to complement the cell cycle arrest or transcriptional defect observed at 39.5°C. These data suggest that TAFII250 acetyltransferase activity is required for cell cycle progression and regulates the expression of essential proliferative control genes.

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Mechanosensitive Expression of Lamellipodin Governs Cell Cycle Progression and Intracellular Stiffness

10.1101/2020.10.30.362624 ◽

2020 ◽

Author(s):

Joseph A. Brazzo ◽

Kwonmoo Lee ◽

Yongho Bae

Keyword(s):

Cell Cycle ◽

Cell Proliferation ◽

Cell Migration ◽

Cell Cycle Progression ◽

Molecular Mechanisms ◽

Cycle Progression ◽

Cellular Processes ◽

M Phase ◽

And Migration ◽

In Cells

SUMMARYCells exhibit pathological behaviors in response to increased extracellular matrix (ECM) stiffness, including accelerated cell proliferation and migration [1–9], which are correlated with increased intracellular stiffness and tension [2, 3, 10–12]. The biomechanical signal transduction of ECM stiffness into relevant molecular signals and resultant cellular processes is mediated through multiple proteins associated with the actin cytoskeleton in lamellipodia [2, 3, 10, 11, 13]. However, the molecular mechanisms by which lamellipodial dynamics regulate cellular responses to ECM stiffening remain unclear. Previous work described that lamellipodin, a phosphoinositide- and actin filament-binding protein that is known mostly for controlling cell migration [14–21], promotes ECM stiffness-mediated early cell cycle progression [2], revealing a potential commonality between the mechanisms controlling stiffness-dependent cell migration and those controlling cell proliferation. However, i) whether and how ECM stiffness affects the levels of lamellipodin expression and ii) whether stiffness-mediated lamellipodin expression is required throughout cell cycle progression and for intracellular stiffness have not been explored. Here, we show that the levels of lamellipodin expression in cells are significantly increased by a stiff ECM and that this stiffness-mediated lamellipodin upregulation persistently stimulates cell cycle progression and intracellular stiffness throughout the cell cycle, from the early G1 phase to M phase. Finally, we show that both Rac activation and intracellular stiffening are required for the mechanosensitive induction of lamellipodin. More specifically, inhibiting Rac1 activation in cells on stiff ECM reduces the levels of lamellipodin expression, and this effect is reversed by the overexpression of activated Rac1 in cells on soft ECM. We thus propose that lamellipodin is a critical molecular lynchpin in the control of mechanosensitive cell cycle progression and intracellular stiffness.

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Cyclin F-Chk1 synthetic lethality mediated by E2F1 degradation

10.1101/509810 ◽

2019 ◽

Author(s):

Kamila Burdova ◽

Hongbin Yang ◽

Roberta Faedda ◽

Samuel Hume ◽

Daniel Ebner ◽

...

Keyword(s):

Cell Cycle ◽

Dna Replication ◽

Cell Cycle Progression ◽

Kinase Inhibitors ◽

Synthetic Lethality ◽

Checkpoint Inhibitors ◽

Dependent Manner ◽

Cycle Progression ◽

Multiple Substrates ◽

Cyclin F

SummaryCyclins are central engines of cell cycle progression when partnered with Cyclin Dependent Kinases (CDKs). Among the different cyclins controlling cell cycle progression, cyclin F does not partner with a CDK, but forms an E3 ubiquitin ligase, assembling through the F-box domain, an Skp1-Cul1-F-box (SCF) module. Although multiple substrates of cyclin F have been identified the vulnerabilities of cells lacking cyclin F are not known. Thus, we assessed viability of cells lacking cyclin F upon challenging cells with more than 200 kinase inhibitors. The screen revealed a striking synthetic lethality between Chk1 inhibition and cyclin F loss. Chk1 inhibition in cells lacking cyclin F leads to DNA replication catastrophe. The DNA replication catastrophe depends on the accumulation of E2F1 in cyclin F depleted cells. We observe that SCFcyclin F promotes E2F1 degradation after Chk1 inhibitors in a CDK dependent manner. Thus, Cyclin F restricts E2F1 activity during cell cycle and upon checkpoint inhibition to prevent DNA replication stress. Our findings pave the way for patient selection in the clinical use of checkpoint inhibitors.

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Src-transformed cells hijack mitosis to extrude from the epithelium

10.1101/246199 ◽

2018 ◽

Author(s):

Katarzyna A. Anton ◽

Mihoko Kajita ◽

Rika Narumi ◽

Yasuyuki Fujita ◽

Masazumi Tada

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Apical Part ◽

Transformed Cells ◽

Cycle Progression ◽

Cellular Processes ◽

Initial Stage ◽

Apical Extrusion

AbstractAt the initial stage of carcinogenesis single mutated cells appear within an epithelium. Mammalian in vitro experiments show that potentially cancerous cells undergo live apical extrusion from normal monolayers. However, the mechanism underlying this process in vivo remains poorly understood. Mosaic expression of the oncogene vSrc in a simple epithelium of the early zebrafish embryo results in apical extrusion of transformed cells. Here we find that during extrusion components of the cytokinetic ring are recruited to adherens junctions of transformed cells, stimulating formation of a misoriented pseudo cytokinetic ring. During extrusion, the ring constricts and separates the basal from the apical part of the cell releasing both from the epithelium. This process requires cell cycle progression and occurs immediately after vSrc-transformed cell enters mitosis. To achieve extrusion, vSrc coordinates cell cycle progression, junctional integrity, cell survival and apicobasal polarity. Without vSrc, modulating these cellular processes reconstitutes vSrc-like extrusion, confirming their sufficiency for this process.

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Evidence for a Structural Relationship between BRCT Domains and the Helicase Domains of the Replication Initiators Encoded by the Polyomaviridae and Papillomaviridae Families of DNA Tumor Viruses

Journal of Virology ◽

10.1128/jvi.00553-08 ◽

2008 ◽

Vol 82 (17) ◽

pp. 8849-8862 ◽

Cited By ~ 2

Author(s):

Anuradha Kumar ◽

Woo S. Joo ◽

Gretchen Meinke ◽

Stephanie Moine ◽

Elena N. Naumova ◽

...

Keyword(s):

Cell Cycle ◽

Dna Repair ◽

Cell Cycle Progression ◽

Cell Cycle Control ◽

Cellular Proteins ◽

Cycle Progression ◽

Cellular Processes ◽

Tumor Viruses ◽

Cellular Pathways ◽

Regulation Of Cell Cycle

ABSTRACT Studies of DNA tumor viruses have provided important insights into fundamental cellular processes and oncogenic transformation. They have revealed, for example, that upon expression of virally encoded proteins, cellular pathways involved in DNA repair and cell cycle control are disrupted. Herein, evidence is presented that BRCT-related regions are present in the helicase domains of the viral initiators encoded by the Polyomaviridae and Papillomaviridae viral families. Of interest, BRCT domains in cellular proteins recruit factors involved in diverse pathways, including DNA repair and the regulation of cell cycle progression. Therefore, the viral BRCT-related regions may compete with host BRCT domains for particular cellular ligands, a process that would help to explain the pleiotropic effects associated with infections with many DNA tumor viruses.

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