1
|
Kim BH, Koh HC. The role of CK2 in the regulation of mitochondrial autophagy induced by rotenone. Toxicol Lett 2023; 382:1-12. [PMID: 37156403 DOI: 10.1016/j.toxlet.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 04/17/2023] [Accepted: 05/04/2023] [Indexed: 05/10/2023]
Abstract
CK2 regulates receptor-mediated mitophagy that removes damaged mitochondria. The PINK1/Parkin pathways also involve mitochondrial clearance through mitophagy. However, it is not clear whether CK2 regulates PINK1/Parkin-dependent mitophagy in response to stress. Rotenone treatment showed a decrease of FUNDC1 expression in the mitochondrial fraction of SH-SY5Y and HeLa cells, but an increase of PINK1/Parkin expression only in SH-SY5Y cells. Interestingly, CK2 inhibition increased mitochondrial LC3II expression in rotenone-treated HeLa cells, whereas it decreased in SH-SY5Y cells, indicating that CK2 mediates rotenone-induced mitophagy in dopaminergic neurons. Furthermore, FUNDC1 expression increased in rotenone-treated SH-SY5Y cells by CK2 inhibition, whereas it decreased in HeLa cells. CK2 inhibition also blocked the increase of Drp1, PINK1 and Parkin translocation into mitochondria and decrease of PGAM5 expression in rotenone-treated SH-SY5Y cells. As expected, rotenone treatment in PGAM5-knockdown cells reduced the expression of PINK1 and Parkin and decrease of LC3II expression. Interestingly, we observed that knockdown of CK2α or PGAM5 induced a further increase in caspase-3 expression. These results suggest that PINK1/Parkin-dependent mitophagy was dominant over FUNDC1 receptor-mediated mitophagy. Collectively, our findings suggest that CK2 can positively induce PINK1/Parkin-dependent mitophagy, and that mitophagy regulates cytoprotective effects by CK2 signaling in dopaminergic neurons. DATA AVAILABILITY STATEMENT: All data generated or analyzed during this study are available upon request.
Collapse
Affiliation(s)
- Beom Hee Kim
- Department of Pharmacology, College of Medicine, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea; Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea
| | - Hyun Chul Koh
- Department of Pharmacology, College of Medicine, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea; Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea; Hanyang Biomedical Research Institute, 222 Wangsimni-ro, Seongdong-gu, 04763, Seoul, Republic of Korea.
| |
Collapse
|
2
|
Recurrent sequence evolution after independent gene duplication. BMC Evol Biol 2020; 20:98. [PMID: 32770961 PMCID: PMC7414715 DOI: 10.1186/s12862-020-01660-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 07/17/2020] [Indexed: 11/10/2022] Open
Abstract
Background Convergent and parallel evolution provide unique insights into the mechanisms of natural selection. Some of the most striking convergent and parallel (collectively recurrent) amino acid substitutions in proteins are adaptive, but there are also many that are selectively neutral. Accordingly, genome-wide assessment has shown that recurrent sequence evolution in orthologs is chiefly explained by nearly neutral evolution. For paralogs, more frequent functional change is expected because additional copies are generally not retained if they do not acquire their own niche. Yet, it is unknown to what extent recurrent sequence differentiation is discernible after independent gene duplications in different eukaryotic taxa. Results We develop a framework that detects patterns of recurrent sequence evolution in duplicated genes. This is used to analyze the genomes of 90 diverse eukaryotes. We find a remarkable number of families with a potentially predictable functional differentiation following gene duplication. In some protein families, more than ten independent duplications show a similar sequence-level differentiation between paralogs. Based on further analysis, the sequence divergence is found to be generally asymmetric. Moreover, about 6% of the recurrent sequence evolution between paralog pairs can be attributed to recurrent differentiation of subcellular localization. Finally, we reveal the specific recurrent patterns for the gene families Hint1/Hint2, Sco1/Sco2 and vma11/vma3. Conclusions The presented methodology provides a means to study the biochemical underpinning of functional differentiation between paralogs. For instance, two abundantly repeated substitutions are identified between independently derived Sco1 and Sco2 paralogs. Such identified substitutions allow direct experimental testing of the biological role of these residues for the repeated functional differentiation. We also uncover a diverse set of families with recurrent sequence evolution and reveal trends in the functional and evolutionary trajectories of this hitherto understudied phenomenon.
Collapse
|
3
|
Zhang Y, Zhu Z, Ding H, Wan S, Zhang X, Li Y, Ji J, Wang X, Zhang M, Ye SD. β-catenin stimulates Tcf7l1 degradation through recruitment of casein kinase 2 in mouse embryonic stem cells. Biochem Biophys Res Commun 2020; 524:280-287. [PMID: 31987502 DOI: 10.1016/j.bbrc.2020.01.074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 01/13/2020] [Indexed: 11/18/2022]
Abstract
Activation of the Wnt/β-catenin signaling pathway by the inhibition of glycogen synthase kinase-3 (GSK-3) will induce Tcf7l1 protein degradation to effectively promote embryonic stem cell (ESC) self-renewal. However, the exact mechanism remains unclear. Here, we found that inhibition of casein kinase 2 (Csnk2) by TBB or DMAT was sufficient to block the reduction of the Tcf7l1 protein induced by CHIR99021, a specific inhibitor of GSK-3. Similarly, downregulation of Csnk2 increased the Tcf7l1 level. In contrast, overexpression of Csnk2 significantly decreased Tcf7l1 protein stability in mouse ESCs. Notably, Csnk2α1 controls Tcf7l1 turnover to a greater degree than the other two isoforms of Csnk2, Csnk2α2 and Csnk2β, as Csnk2α1-overexpressing mouse ESCs exhibited the lowest level of Tcf7l1. Csnk2α1 interacted with and phosphorylated Tcf7l1. In addition, the association of Csnk2α1 and Tcf7l1 was enhanced by CHIR99021. Our study demonstrated, for the first time, that Csnk2 is involved in Tcf7l1 turnover mediated by the Wnt/β-catenin signaling pathway. These results expand our understanding of the function and circuit of Wnt/β-catenin signaling pathway in ESCs.
Collapse
Affiliation(s)
- Yan Zhang
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Zhenhua Zhu
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Huiwen Ding
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Shengpeng Wan
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Xinbao Zhang
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Yuting Li
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Junxiang Ji
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Xin Wang
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Meng Zhang
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Shou-Dong Ye
- Center for Stem Cell and Translational Medicine, School of Life Sciences & Institute of Physical Science and Information Technology, Anhui University, Hefei, 230601, PR China.
| |
Collapse
|
4
|
Predicting CK2 beta-dependent substrates using linear patterns. Biochem Biophys Rep 2015; 4:20-27. [PMID: 29124183 PMCID: PMC5668876 DOI: 10.1016/j.bbrep.2015.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 08/14/2015] [Accepted: 08/17/2015] [Indexed: 12/13/2022] Open
Abstract
CK2 is a constitutively active Ser/Thr protein kinase deregulated in cancer and other pathologies, responsible for about the 20% of the human phosphoproteome. The holoenzyme is a complex composed of two catalytic (α or α´) and two regulatory (β) subunits, with individual subunits also coexisting in the cell. In the holoenzyme, CK2β is a substrate-dependent modulator of kinase activity. Therefore, a comprehensive characterization of CK2 cellular function should firstly address which substrates are phosphorylated exclusively when CK2β is present (class-III or beta-dependent substrates). However, current experimental constrains limit this classification to a few substrates. Here, we took advantage of motif-based prediction and designed four linear patterns for predicting class-III behavior in sets of experimentally determined CK2 substrates. Integrating high-throughput substrate prediction, functional classification and network analysis, our results suggest that beta-dependent phosphorylation might exert particular regulatory roles in viral infection and biological processes/pathways like apoptosis, DNA repair and RNA metabolism. It also pointed, that human beta-dependent substrates are mainly nuclear, a few of them shuttling between nuclear and cytoplasmic compartments. The designed linear patterns assist CK2 beta-dependent substrates prediction. A high-throughput prediction of CK2 beta-dependent substrates was performed in several organisms including human, mouse and rat. The functional classification indicated a role of CK2 beta-dependent regulation in viral infection, apoptosis, DNA repair and RNA metabolism. The functional classification indicated that human CK2 beta-dependent substrates are mainly nuclear with a number of them also found in cytoplasm.
Collapse
|
5
|
Abstract
What has been will be again, what has been done will be done again; there is nothing new under the sun. -Ecclesiastes 1:9 (New International Version) Posttranscriptional regulation of gene expression has an important role in defining the phenotypic characteristics of an organism. Well-defined steps in mRNA metabolism that occur in the nucleus-capping, splicing, and polyadenylation-are mechanistically linked to the process of transcription. Recent evidence suggests another link between RNA polymerase II (Pol II) and a posttranscriptional process that occurs in the cytoplasm-mRNA decay. This conclusion appears to represent a conundrum. How could mRNA synthesis in the nucleus and mRNA decay in the cytoplasm be mechanistically linked? After a brief overview of mRNA processing, we will review the recent evidence for transcription-coupled mRNA decay and the possible involvement of Snf1, the Saccharomyces cerevisiae ortholog of AMP-activated protein kinase, in this process.
Collapse
|
6
|
Liu H, Wang H, Teng M, Li X. The multiple nucleotide-divalent cation binding modes of Saccharomyces cerevisiae CK2α indicate a possible co-substrate hydrolysis product (ADP/GDP) release pathway. ACTA ACUST UNITED AC 2014; 70:501-13. [PMID: 24531484 DOI: 10.1107/s1399004713027879] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 10/10/2013] [Indexed: 12/14/2022]
Abstract
CK2 is a ubiquitous and conserved protein kinase in eukaryotic organisms and is important in many biological processes. It is unique in maintaining constitutive activity and in using both ATP and GTP as phosphor donors. In this study, crystal structures of recombinant Saccharomyces cerevisiae CK2α (scCK2α) complexed with GMPPNP, ATP and AMPPN with either Mg2+ or Mn2+ as the coordinated divalent cation are presented. The overall structure of scCK2α shows high similarity to its homologous proteins by consisting of two domains with the co-substrate lying in the cleft between them. However, three characteristic features distinguish scCK2α from its homologues. Firstly, the Lys45-Glu53 and Arg48-Glu53 interactions in scCK2α lead Lys50 to adopt a unique conformation that is able to stabilize the γ-phosphate of the co-substrate, which makes the existence of the `essential divalent cation' not so essential. The multiple nucleotide-divalent cation binding modes of the active site of scCK2α are apparently different from the two-divalent-cation-occupied active site of Zea mays CK2α and human CK2α. Secondly, conformational change of Glu53 in scCK2α-AMPPN breaks its interaction with Lys45 and Arg48; as a result, the co-substrate binding pocket becomes more open. This may suggest a clue to a possible ADP/GDP-release pathway, because the NE1 atom of the Trp in the `DWG motif' of CK2α forms a hydrogen bond to the O atom of Leu212, which seems to make ADP release by means of the `DFG-in flip to DFG-out' model found in most eukaryotic protein kinases impossible. Coincidentally, two sulfate ions which may mimic two phosphate groups were captured by Arg161 and Lys197 around the pocket. Mutagenesis and biochemical experiments on R161A and K197A mutants support the above proposal. Finally, scCK2α is unique in containing an insertion region whose function had not been identified in previous research. It is found that the insertion region contributes to maintaining the constitutively active conformation of the scCK2α catalytic site, but does not participate in interaction with the regulatory subunits.
Collapse
Affiliation(s)
- Huihui Liu
- School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| | - Hong Wang
- School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| | - Maikun Teng
- School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| | - Xu Li
- School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, People's Republic of China
| |
Collapse
|
7
|
Kanki T, Kurihara Y, Jin X, Goda T, Ono Y, Aihara M, Hirota Y, Saigusa T, Aoki Y, Uchiumi T, Kang D. Casein kinase 2 is essential for mitophagy. EMBO Rep 2013; 14:788-94. [PMID: 23897086 DOI: 10.1038/embor.2013.114] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Revised: 07/07/2013] [Accepted: 07/11/2013] [Indexed: 01/05/2023] Open
Abstract
Mitophagy is a process that selectively degrades mitochondria. When mitophagy is induced in yeast, the mitochondrial outer membrane protein Atg32 is phosphorylated, interacts with the adaptor protein Atg11 and is recruited into the vacuole with mitochondria. We screened kinase-deleted yeast strains and found that CK2 is essential for Atg32 phosphorylation, Atg32-Atg11 interaction and mitophagy. Inhibition of CK2 specifically blocks mitophagy, but not macroautophagy, pexophagy or the Cvt pathway. In vitro, CK2 phosphorylates Atg32 at serine 114 and serine 119. We conclude that CK2 regulates mitophagy by directly phosphorylating Atg32.
Collapse
Affiliation(s)
- Tomotake Kanki
- Laboratory of Biosignaling, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Predominance of CK2α over CK2α′ in the mammalian brain. Mol Cell Biochem 2011; 356:169-75. [DOI: 10.1007/s11010-011-0963-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 06/24/2011] [Indexed: 10/18/2022]
|
9
|
Pickin KA, Ezenwajiaku N, Overcash H, Sethi M, Knecht MR, Paumi CM. Suppression of Ycf1p function by Cka1p-dependent phosphorylation is attenuated in response to salt stress. FEMS Yeast Res 2010; 10:839-57. [PMID: 20812950 DOI: 10.1111/j.1567-1364.2010.00677.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The yeast vacuolar membrane protein Ycf1p and its mammalian counterpart, MRP1, belong to the ABCC subfamily of ATP-binding cassette transporters. Genetic evidence suggests that the yeast casein kinase 2α, Cka1p, negatively regulates Ycf1p function via phosphorylation of Ser251 within the N-terminus. In this study, we provide strong evidence that Cka1p regulates Ycf1p function via phosphorylation of Ser251. We show that the CK2 holoenzyme interacts with Ycf1p. However, genetic analysis suggests that only Cka1p is required for Ser251 phosphorylation, as the deletion of CKA1 significantly reduces Ser251 phosphorylation in vivo. Furthermore, purified recombinant Cka1p phosphorylates a Ycf1p-derived peptide containing Ser251. We also demonstrate that Ycf1p function is induced in response to high salt stress. Induction of the Ycf1p function strongly correlates with reduced phosphorylation of Ser251. Importantly, Cka1p activity in vivo is similarly reduced in response to salt stress, consistent with our finding that Cka1p directly phosphorylates Ser251 of Ycf1p. We provide genetic and biochemical evidence that strongly suggests that the induction of Ycf1p function is the result of decreased phosphorylation of Ser251. In conclusion, our work demonstrates a novel biochemical role for Cka1p regulation of Ycf1p function in the cellular response of yeast to salt stress.
Collapse
Affiliation(s)
- Kerry A Pickin
- Department of Toxicology, University of Kentucky, Lexington, KY 40536, USA
| | | | | | | | | | | |
Collapse
|
10
|
Ye T, Elbing K, Hohmann S. The pathway by which the yeast protein kinase Snf1p controls acquisition of sodium tolerance is different from that mediating glucose regulation. MICROBIOLOGY-SGM 2008; 154:2814-2826. [PMID: 18757815 DOI: 10.1099/mic.0.2008/020149-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
It recently became apparent that the highly conserved Snf1p protein kinase plays roles in controlling different cellular processes in the yeast Saccharomyces cerevisiae, in addition to its well-known function in glucose repression/derepression. We have previously reported that Snf1p together with Gis4p controls ion homeostasis by regulating expression of ENA1, which encodes the Ena1p Na(+) extrusion system. In this study we found that Snf1p is rapidly phosphorylated when cells are exposed to NaCl and this phosphorylation is required for the role of Snf1p in Na(+) tolerance. In contrast to activation by low glucose levels, the salt-induced phosphorylation of Snf1p promoted neither phosphorylation nor nuclear export of the Mig1p repressor. The mechanism that prevents Mig1p phosphorylation by active Snf1p under salt stress does not involve either hexokinase PII or the Gis4p regulator. Instead, Snf1p may mediate upregulation of ENA1 expression via the repressor Nrg1p. Activation of Snf1p in response to glucose depletion requires any of the three upstream protein kinases Sak1p, Tos3p and Elm1p, with Sak1p playing the most prominent role. The same upstream kinases were required for salt-induced Snf1p phosphorylation, and also under these conditions Sak1p played the most prominent role. Unexpectedly, however, it appears that Elm1p plays a dual role in acquisition of salt tolerance by activating Snf1p and in a presently unknown parallel pathway. Together, these results indicate that under salt stress Snf1p takes part in a different pathway from that during glucose depletion and this role is performed together as well as in parallel with its upstream kinase Elm1p. Snf1p appears to be part of a wider functional network than previously anticipated and the full complexity of this network remains to be elucidated.
Collapse
Affiliation(s)
- Tian Ye
- Department of Cell and Molecular Biology/Microbiology, University of Gothenburg, Box 462, S-40530 Göteborg, Sweden
| | - Karin Elbing
- Department of Cell and Molecular Biology/Microbiology, University of Gothenburg, Box 462, S-40530 Göteborg, Sweden
| | - Stefan Hohmann
- Department of Cell and Molecular Biology/Microbiology, University of Gothenburg, Box 462, S-40530 Göteborg, Sweden
| |
Collapse
|
11
|
ESCRT-III protein Snf7 mediates high-level expression of the SUC2 gene via the Rim101 pathway. EUKARYOTIC CELL 2008; 7:1888-94. [PMID: 18806212 DOI: 10.1128/ec.00194-08] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The yeast (Saccharomyces cerevisiae) Snf7 family consists of six highly charged, coiled-coil-forming proteins involved in multivesicular body (MVB) formation. Although all proteins perform a common function at late endosomes, individual mutants also show distinct phenotypes. This suggests that Snf7 homologues have additional functions separate from their role in MVB formation. In this report, we explored the molecular basis for the sucrose-nonfermenting phenotype of snf7 mutants. Our Northern blotting experiments provide evidence that Snf7 is involved in the regulation of SUC2 transcription. The Snf7-dependent regulation of SUC2 transcription does not appear to involve the transcription factor Mig1, since Mig1 phosphorylation after glucose derepression was not affected in a Deltasnf7 mutant. Instead, we show that Snf7 influences SUC2 expression by regulating the level of the transcription factor Nrg1. Snf7 exerts its effects on Nrg1 levels through activation of the transcription factor Rim101, which is part of the yeast alkaline response pathway ("Rim101 pathway"). This is supported by the findings that deletion of RIM101 or overexpression of NRG1 from the ADH1 promoter leads to the same SUC2 expression level as deletion of SNF7. In addition, deletion of other components of the Rim101 pathway, like RIM13 and RIM20, led to the same growth phenotype on raffinose media as deletion of SNF7. Furthermore, Snf7 turned out to be dispensable for SUC2 expression in an NRG1 deletion background. Thus, the effects of Snf7 on SUC2 expression can be completely accounted for by its effect on Nrg1 levels.
Collapse
|
12
|
Function and regulation of the Saccharomyces cerevisiae ENA sodium ATPase system. EUKARYOTIC CELL 2007; 6:2175-83. [PMID: 17951516 DOI: 10.1128/ec.00337-07] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
13
|
Rubenstein EM, Schmidt MC. Mechanisms regulating the protein kinases of Saccharomyces cerevisiae. EUKARYOTIC CELL 2007; 6:571-83. [PMID: 17337635 PMCID: PMC1865659 DOI: 10.1128/ec.00026-07] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Eric M Rubenstein
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, W1247 Biomedical Science Tower, Pittsburgh, PA 15261, USA
| | | |
Collapse
|
14
|
John Wiley & Sons, Ltd.. Current awareness on yeast. Yeast 2007. [DOI: 10.1002/yea.1323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
15
|
Chiang LY, Sheppard DC, Bruno VM, Mitchell AP, Edwards JE, Filler SG. Candida albicans protein kinase CK2 governs virulence during oropharyngeal candidiasis. Cell Microbiol 2006; 9:233-45. [PMID: 16939537 DOI: 10.1111/j.1462-5822.2006.00784.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
To identify Candida albicans genes whose proteins are necessary for host cell interactions and virulence, a collection of C. albicans insertion mutants was screened for strains with reduced capacity to damage endothelial cells in vitro. This screen identified CKA2. CKA2 and its homologue CKA1 encode the catalytic subunits of the protein kinase CK2. cka2delta/cka2delta strains of C. albicans were constructed and found to have significantly reduced capacity to damage both endothelial cells and an oral epithelial cell line in vitro. Although these strains invaded endothelial cells similarly to the wild-type strain, they were defective in oral epithelial cell invasion. They were also hypersusceptible to hydrogen peroxide, but not to high salt or to cell wall damaging agents. A cka1delta/cka1delta mutant caused normal damage to both endothelial cells and oral epithelial cells, and it was not hypersusceptible to hydrogen peroxide. However, overexpression of CKA1 in a cka2delta/cka2delta strain restored wild-type phenotype. Although the cka2delta/cka2delta mutant had normal virulence in the mouse model of haematogenously disseminated candidiasis, it had significantly attenuated virulence in the mouse model of oropharyngeal candidiasis. Therefore, Cka2p governs the interactions of C. albicans with endothelial and oral epithelial cells in vitro and virulence during oropharyngeal candidiasis.
Collapse
Affiliation(s)
- Lisa Y Chiang
- Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA, USA
| | | | | | | | | | | |
Collapse
|