Comparative Phenotypic, Proteomic, and Phosphoproteomic Analysis Reveals Different Roles of Serine/Threonine Phosphatase and Kinase in the Growth, Cell Division, and Pathogenicity of Streptococcus suis

Eukaryote-like serine/threonine kinases (STKs) and cognate phosphatases (STPs) comprise an important regulatory system in many bacterial pathogens. The complexity of this regulatory system has not been fully understood due to the presence of multiple STKs/STPs in many bacteria and their multiple substrates involved in many different physiological and pathogenetic processes. Streptococci are the best materials for the study due to a single copy of the gene encoding STK and its cognate STP. Although several studies have been done to investigate the roles of STK and STP in zoonotic Streptococcus suis, respectively, few studies were performed on the coordinated regulatory roles of this system. In this study, we carried out a systemic study on STK/STP in S. suis by using a comparative phenotypic, proteomic, and phosphoproteomic analysis. Mouse infection assays revealed that STK played a much more important role in S. suis pathogenesis than STP. The ∆stk and ∆stp∆stk strains, but not ∆stp, showed severe growth retardation. Moreover, both ∆stp and ∆stk strains displayed defects in cell division, but they were abnormal in different ways. The comparative proteomics and phosphoproteomics revealed that deletion of stk or stp had a significant influence on protein expression. Interestingly, more virulence factors were found to be downregulated in ∆stk than ∆stp. In ∆stk strain, a substantial number of the proteins with a reduced phosphorylation level were involved in cell division, energy metabolism, and protein translation. However, only a few proteins showed increased phosphorylation in ∆stp, which also included some proteins related to cell division. Collectively, our results show that both STP and STK are critical regulatory proteins for S. suis and that STK seems to play more important roles in growth, cell division, and pathogenesis.

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Identification of a single-copy gene encoding a Type I chlorophyll a/b-binding polypeptide of photosystem I in Arabidopsis thaliana

Physiologia Plantarum ◽

10.1034/j.1399-3054.1992.840410.x ◽

1992 ◽

Vol 84 (4) ◽

pp. 561-567 ◽

Cited By ~ 1

Author(s):

Poul E. Jensen ◽

Michael Kristensen ◽

Tine Hoff ◽

Jan Lehmbeck ◽

Bjarne M. Stummann ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Chlorophyll A ◽

Photosystem I ◽

Single Copy ◽

Type I ◽

Single Copy Gene ◽

Gene Encoding ◽

Copy Gene

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The gene encoding the transcription factor SCIP has features of an expressed retroposon.

Molecular and Cellular Biology ◽

10.1128/mcb.11.9.4642 ◽

1991 ◽

Vol 11 (9) ◽

pp. 4642-4650 ◽

Cited By ~ 36

Author(s):

R Kuhn ◽

E S Monuki ◽

G Lemke

Keyword(s):

Transcription Factor ◽

Schwann Cells ◽

Cpg Island ◽

Single Copy ◽

Gene Encoding ◽

Intronless Gene ◽

Gene Comparison ◽

Acid Protein ◽

Central Nervous Systems ◽

Glial Progenitor Cells

SCIP is a POU domain transcription factor expressed by glial progenitor cells in the peripheral and central nervous systems (dividing Schwann cells and O-2A cells, respectively), where it appears to act as a repressor of myelin-specific genes. We have isolated genomic clones encoding the rat SCIP gene. Comparison of the structure of these clones with genomic Southern blots and SCIP cDNAs demonstrates that SCIP is encoded in a single-copy, intronless gene that has the general features of an expressed retroposon. This gene contributes to an extended CpG island. It is transcribed to produce a 3.1-kb mRNA that encodes a 451-amino-acid protein with a predicted molecular mass of 45 kDa. Immunopurified SCIP antibodies specifically recognize a nuclear protein of this size in cultured proliferating Schwann cells, and gel shift analyses demonstrate that this protein is the predominant octamer-binding protein in these cells.

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Yeast ribosomal protein L1 is required for the stability of newly synthesized 5S rRNA and the assembly of 60S ribosomal subunits

Molecular and Cellular Biology ◽

10.1128/mcb.13.5.2835-2845.1993 ◽

1993 ◽

Vol 13 (5) ◽

pp. 2835-2845

Author(s):

M Deshmukh ◽

Y F Tsay ◽

A G Paulovich ◽

J L Woolford

Keyword(s):

Ribosomal Protein ◽

Ribosomal Subunit ◽

Single Copy ◽

5S Rrna ◽

Gene Encoding ◽

Ribosomal Subunits ◽

Ribosomal Protein L1 ◽

The Stability ◽

And Function

Ribosomal protein L1 from Saccharomyces cerevisiae binds 5S rRNA and can be released from intact 60S ribosomal subunits as an L1-5S ribonucleoprotein (RNP) particle. To understand the nature of the interaction between L1 and 5S rRNA and to assess the role of L1 in ribosome assembly and function, we cloned the RPL1 gene encoding L1. We have shown that RPL1 is an essential single-copy gene. A conditional null mutant in which the only copy of RPL1 is under control of the repressible GAL1 promoter was constructed. Depletion of L1 causes instability of newly synthesized 5S rRNA in vivo. Cells depleted of L1 no longer assemble 60S ribosomal subunits, indicating that L1 is required for assembly of stable 60S ribosomal subunits but not 40S ribosomal subunits. An L1-5S RNP particle not associated with ribosomal particles was detected by coimmunoprecipitation of L1 and 5S rRNA. This pool of L1-5S RNP remained stable even upon cessation of 60S ribosomal subunit assembly by depletion of another ribosomal protein, L16. Preliminary results suggest that transcription of RPL1 is not autogenously regulated by L1.

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The structural mechanics of cell division in Trypanosoma brucei

Biochemical Society Transactions ◽

10.1042/bst0360421 ◽

2008 ◽

Vol 36 (3) ◽

pp. 421-424 ◽

Cited By ~ 30

Author(s):

Sue Vaughan ◽

Keith Gull

Keyword(s):

Cell Division ◽

Trypanosoma Brucei ◽

Mammalian Cells ◽

Reverse Genetics ◽

Protozoan Parasite ◽

Cell Types ◽

Single Copy ◽

Structural Mechanics ◽

Sub Saharan Africa ◽

Mammalian Host

Undoubtedly, there are fundamental processes driving the structural mechanics of cell division in eukaryotic organisms that have been conserved throughout evolution and are being revealed by studies on organisms such as yeast and mammalian cells. Precision of structural mechanics of cytokinesis is however probably no better illustrated than in the protozoa. A dramatic example of this is the protozoan parasite Trypanosoma brucei, a unicellular flagellated parasite that causes a devastating disease (African sleeping sickness) across Sub-Saharan Africa in both man and animals. As trypanosomes migrate between and within a mammalian host and the tsetse vector, there are periods of cell proliferation and cell differentiation involving at least five morphologically distinct cell types. Much of the existing cytoskeleton remains intact during these processes, necessitating a very precise temporal and spatial duplication and segregation of the many single-copy organelles. This structural precision is aiding progress in understanding these processes as we apply the excellent reverse genetics and post-genomic technologies available in this system. Here we outline our current understanding of some of the structural aspects of cell division in this fascinating organism.

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Automated CUT&Tag profiling of chromatin heterogeneity in mixed-lineage leukemia

Nature Genetics ◽

10.1038/s41588-021-00941-9 ◽

2021 ◽

Author(s):

Derek H. Janssens ◽

Michael P. Meers ◽

Steven J. Wu ◽

Ekaterina Babaeva ◽

Soheil Meshinchi ◽

...

Keyword(s):

Single Cell ◽

Binding Sites ◽

Therapeutic Agents ◽

Mixed Lineage Leukemia ◽

Regulatory Proteins ◽

Chromosomal Translocations ◽

Tumor Subtype ◽

Gene Encoding ◽

Lysine Methyltransferase ◽

Chromatin Profiling

AbstractAcute myeloid and lymphoid leukemias often harbor chromosomal translocations involving the KMT2A gene, encoding the KMT2A lysine methyltransferase (also known as mixed-lineage leukemia-1), and produce in-frame fusions of KMT2A to other chromatin-regulatory proteins. Here we map fusion-specific targets across the genome for diverse KMT2A oncofusion proteins in cell lines and patient samples. By modifying CUT&Tag chromatin profiling for full automation, we identify common and tumor-subtype-specific sites of aberrant chromatin regulation induced by KMT2A oncofusion proteins. A subset of KMT2A oncofusion-binding sites are marked by bivalent (H3K4me3 and H3K27me3) chromatin signatures, and single-cell CUT&Tag profiling reveals that these sites display cell-to-cell heterogeneity suggestive of lineage plasticity. In addition, we find that aberrant enrichment of H3K4me3 in gene bodies is sensitive to Menin inhibitors, demonstrating the utility of automated chromatin profiling for identifying therapeutic vulnerabilities. Thus, integration of automated and single-cell CUT&Tag can uncover epigenomic heterogeneity within patient samples and predict sensitivity to therapeutic agents.

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The Erwinia chrysanthemi 3937 PhoQ Sensor Kinase Regulates Several Virulence Determinants

Journal of Bacteriology ◽

10.1128/jb.188.8.3088-3098.2006 ◽

2006 ◽

Vol 188 (8) ◽

pp. 3088-3098 ◽

Cited By ~ 38

Author(s):

Balakrishnan Venkatesh ◽

Lavanya Babujee ◽

Hui Liu ◽

Pete Hedley ◽

Takashi Fujikawa ◽

...

Keyword(s):

Virulence Factors ◽

Regulatory System ◽

Soft Rot ◽

Erwinia Chrysanthemi ◽

Pcr Analysis ◽

Sensor Kinase ◽

Virulence Determinants ◽

Gene Encoding ◽

Reverse Transcription Pcr ◽

Two Component

ABSTRACT The PhoPQ two-component system regulates virulence factors in Erwinia chrysanthemi, a pectinolytic enterobacterium that causes soft rot in several plant species. We characterized the effect of a mutation in phoQ, the gene encoding the sensor kinase PhoQ of the PhoPQ two-component regulatory system, on the global transcriptional profile of E. chrysanthemi using cDNA microarrays and further confirmed our results by quantitative reverse transcription-PCR analysis. Our results indicate that a mutation in phoQ affects transcription of at least 40 genes, even in the absence of inducing conditions. Enhanced expression of several genes involved in iron metabolism was observed in the mutant, including that of the acs operon that is involved in achromobactin biosynthesis and transport. This siderophore is required for full virulence of E. chrysanthemi, and its expression is governed by the global repressor protein Fur. Changes in gene expression were also observed for membrane transporters, stress-related genes, toxins, and transcriptional regulators. Our results indicate that the PhoPQ system governs the expression of several additional virulence factors and may also be involved in interactions with other regulatory systems.

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RPC53 encodes a subunit of Saccharomyces cerevisiae RNA polymerase C (III) whose inactivation leads to a predominantly G1 arrest.

Molecular and Cellular Biology ◽

10.1128/mcb.12.10.4314 ◽

1992 ◽

Vol 12 (10) ◽

pp. 4314-4326 ◽

Cited By ~ 21

Author(s):

C Mann ◽

J Y Micouin ◽

N Chiannilkulchai ◽

I Treich ◽

J M Buhler ◽

...

Keyword(s):

Cell Division ◽

Amino Acid ◽

Rna Polymerase ◽

Essential Gene ◽

Temperature Sensitive ◽

G1 Arrest ◽

Restrictive Temperature ◽

Amino Acid Residues ◽

Gene Encoding ◽

Carboxy Terminal

RPC53 is shown to be an essential gene encoding the C53 subunit specifically associated with yeast RNA polymerase C (III). Temperature-sensitive rpc53 mutants were generated and showed a rapid inhibition of tRNA synthesis after transfer to the restrictive temperature. Unexpectedly, the rpc53 mutants preferentially arrested their cell division in the G1 phase as large, round, unbudded cells. The RPC53 DNA sequence is predicted to code for a hydrophilic M(r)-46,916 protein enriched in charged amino acid residues. The carboxy-terminal 136 amino acids of C53 are significantly similar (25% identical amino acid residues) to the same region of the human BN51 protein. The BN51 cDNA was originally isolated by its ability to complement a temperature-sensitive hamster cell mutant that undergoes a G1 cell division arrest, as is true for the rpc53 mutants.

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Overexpression of a truncated cyclin B gene arrests Dictyostelium cell division during mitosis

Journal of Cell Science ◽

10.1242/jcs.107.11.3105 ◽

1994 ◽

Vol 107 (11) ◽

pp. 3105-3114 ◽

Cited By ~ 2

Author(s):

Q. Luo ◽

C. Michaelis ◽

G. Weeks

Keyword(s):

Cell Cycle ◽

Cell Division ◽

Cell Growth ◽

Dictyostelium Discoideum ◽

Single Copy ◽

Cyclin B ◽

Dictyostelium Cell ◽

Maximum Accumulation ◽

Sequence Identity ◽

Cyclin Gene

A cyclin gene has been isolated from Dictyostelium discoideum and the available evidence indicates that the gene encodes a B type cyclin. The cyclin box region of the protein encoded by the gene, clb1, has the highest degree of sequence identity with the B-type cyclins of other species. Levels of cyclin B mRNA and protein oscillate during the cell cycle with maximum accumulation of mRNA occurring prior to cell division and maximum levels of protein occurring during cell division. Overexpression of a N-terminally truncated cyclin B protein lacking the destruction box inhibits cell growth by arresting cell division during mitosis. The gene is present as a single copy in the Dictyostelium genome and there is no evidence for any other highly related cyclin B genes.

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