ZIP Kinase, a Novel Serine/Threonine Kinase Which Mediates Apoptosis

ABSTRACT We have identified a novel serine/threonine kinase, designated ZIP kinase, which mediates apoptosis. ZIP kinase contains a leucine zipper structure at its C terminus, in addition to a kinase domain at its N terminus. ZIP kinase physically binds to ATF4, a member of the activating transcription factor/cyclic AMP-responsive element-binding protein (ATF/CREB) family, through interaction between their leucine zippers. The leucine zipper domain is necessary for the homodimerization of ZIP kinase as well as for the activation of kinase. Immunostaining study showed that ZIP kinase localizes in the nuclei. Overexpression of intact ZIP kinase but not catalytically inactive kinase mutants led to the morphological changes of apoptosis in NIH 3T3 cells, suggesting that the cell death-inducing activity of ZIP kinase depends on its intrinsic kinase activity. Interestingly, the catalytic domain of ZIP kinase is closely related to that of death-associated protein kinase (DAP kinase), which is a mediator of apoptosis induced by gamma interferon. Therefore, both ZIP and DAP kinases represent a novel kinase family, which mediates apoptosis through their catalytic activities.

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DdNek2, the first non-vertebrate homologue of human Nek2, is involved in the formation of microtubule-organizing centers

Journal of Cell Science ◽

10.1242/jcs.115.9.1919 ◽

2002 ◽

Vol 115 (9) ◽

pp. 1919-1929

Author(s):

Ralph Gräf

Keyword(s):

Catalytic Activity ◽

Leucine Zipper ◽

Catalytic Domain ◽

Amino Acid Identity ◽

Serine Threonine Kinase ◽

Threonine Kinase ◽

Microtubule Organizing Centers ◽

Terminal Domain ◽

C Terminus ◽

Early Mitosis

Dictyostelium Nek2 (DdNek2) is the first structural and functional non-vertebrate homologue of human Nek2, a NIMA-related serine/threonine kinase required for centrosome splitting in early mitosis. DdNek2 shares 43% overall amino-acid identity with its human counterpart and 54% identity within the catalytic domain. Both proteins can be subdivided in an N-terminal catalytic domain, a leucine zipper and a C-terminal domain. Kinase assays with bacterially expressed DdNek2 and C-terminal deletion mutants revealed that catalytic activity requires the presence of the leucine zipper and that autophosphorylation occurs at the C-terminus. Microscopic analyses with DdNek2 antibodies and expression of a GFP-DdNek2 fusion protein in Dictyostelium showed that DdNek2 is a permanent centrosomal resident and suggested that it is a component of the centrosomal core. The GFP-DdNek2-overexpressing mutants frequently exhibit supernumerary microtubule-organizing centers (MTOCs). This phenotype did not require catalytic activity because it was also observed in cells expressing inactive GFP-K33R. However, it was shown to be caused by overexpression of the C-terminal domain since it also occurred in GFP-mutants expressing only the C-terminus or a leucine zipper/C-terminus construct but not in those mutants expressing only the catalytic domain or a catalytic domain/leucine zipper construct. These results suggest that DdNek2 is involved in the formation of MTOCs. Furthermore, the localization of the GFP-fusion proteins revealed two independent centrosomal targeting domains of DdNek2, one within the catalytic or leucine zipper domain and one in the C-terminal domain.

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The structures of the kinase domain and UBA domain of MPK38 suggest the activation mechanism for kinase activity

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s1399004713027806 ◽

2014 ◽

Vol 70 (2) ◽

pp. 514-521 ◽

Cited By ~ 6

Author(s):

Yong-Soon Cho ◽

Jiho Yoo ◽

Soomin Park ◽

Hyun-Soo Cho

Keyword(s):

Drug Target ◽

Leucine Zipper ◽

Kinase Domain ◽

Activation Mechanism ◽

Activation Loop ◽

Serine Threonine Kinase ◽

Threonine Kinase ◽

Extended Sequence ◽

Uba Domain ◽

Cleft Closure

Murine protein serine/threonine kinase 38 (MPK38) is the murine orthologue of human maternal embryonic leucine-zipper kinase (MELK), which belongs to the SNF1/AMPK family. MELK is considered to be a promising drug target for anticancer therapy because overexpression and hyperactivation of MELK is correlated with several human cancers. Activation of MPK38 requires the extended sequence (ExS) containing the ubiquitin-associated (UBA) linker and UBA domain and phosphorylation of the activation loop. However, the activation mechanism of MPK38 is unknown. This paper reports the crystal structure of MPK38 (T167E), which mimics a phosphorylated state of the activation loop, in complex with AMP-PNP. In the MPK38 structure, the UBA linker forces an inward movement of the αC helix. Phosphorylation of the activation loop then induces movement of the activation loop towards the C-lobe and results in interlobar cleft closure. These processes generate a fully active state of MPK38. This structure suggests that MPK38 has a similar molecular mechanism regulating activation as in other kinases of the SNF1/AMPK family.

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A phyB-PIF1-SPA1 kinase regulatory complex promotes photomorphogenesis in Arabidopsis

Nature Communications ◽

10.1038/s41467-019-12110-y ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 21

Author(s):

Inyup Paik ◽

Fulu Chen ◽

Vinh Ngoc Pham ◽

Ling Zhu ◽

Jeong-Il Kim ◽

...

Keyword(s):

Red Light ◽

Kinase Domain ◽

Serine Threonine Kinase ◽

Threonine Kinase ◽

C Terminus ◽

Subsequent Degradation ◽

Regulatory Complex

Abstract CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1) is a highly conserved E3 ubiquitin ligase from plants to animals and acts as a central repressor of photomorphogenesis in plants. SUPPRESSOR OF PHYA-105 1 family members (SPA1-SPA4) directly interact with COP1 and enhance COP1 activity. Despite the presence of a kinase domain at the N-terminus, no COP1-independent role of SPA proteins has been reported. Here we show that SPA1 acts as a serine/threonine kinase and directly phosphorylates PIF1 in vitro and in vivo. SPAs are necessary for the light-induced phosphorylation, ubiquitination and subsequent degradation of PIF1. Moreover, the red/far-red light photoreceptor phyB interacts with SPA1 through its C-terminus and enhances the recruitment of PIF1 for phosphorylation. These data provide a mechanistic view on how the COP1-SPA complexes serve as an example of a cognate kinase-E3 ligase complex that selectively triggers rapid phosphorylation and removal of its substrates, and how phyB modulates this process to promote photomorphogenesis.

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Functional Domains of Fused, a Serine-Threonine Kinase Required for Signaling in Drosophila

Genetics ◽

10.1093/genetics/142.4.1181 ◽

1996 ◽

Vol 142 (4) ◽

pp. 1181-1198

Author(s):

Pascal Thérond ◽

Georges Alves ◽

Bernadette Limbourg-Bouchon ◽

Hervé Tricoire ◽

Elizabeth Guillemet ◽

...

Keyword(s):

Catalytic Domain ◽

Kinase Domain ◽

In Vitro Mutagenesis ◽

Serine Threonine Kinase ◽

Threonine Kinase ◽

Terminal Domain ◽

Segment Polarity ◽

Protein Functions

Abstract fused (fu) is a segment-polarity gene encoding a putative serine-threonine kinase. In a wild-type context, all fu mutations display the same set of phenotypes. Nevertheless, mutations of the Suppressor of fused [Su(fu)] gene define three classes of alleles (fu0, fuI, fuII). Here, we report the molecular analysis of known fu mutations and the generation of new alleles by in vitro mutagenesis. We show that the Fused (Fu) protein functions in vivo as a kinase. The N-terminal kinase and the extreme C-terminal domains are necessary for Fu+ activity while a central region appears to be dispensable. We observe a striking correlation between the molecular lesions of fu mutations and the phenotype displayed in their interaction with Su(fu). Indeed, fuI alleles which are suppressed by Su(fu) mutations are defined by inframe alterations of the N-terminal catalytic domain whereas the C-terminal domain is missing or altered in all fuII alleles. An unregulated FuII protein, which can be limited to the 80 N-terminal amino acids of the kinase domain, would be responsible for the neomorphic costal-2 phenotype displayed by the fuII-Su(fu) interaction. We propose that the Fu C-terminal domain can differentially regulate the Fu catalytic domain according to cell position in the parasegment.

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Ability of PknA, a mycobacterial eukaryotic-type serine/threonine kinase, to transphosphorylate MurD, a ligase involved in the process of peptidoglycan biosynthesis

Biochemical Journal ◽

10.1042/bj20080234 ◽

2008 ◽

Vol 415 (1) ◽

pp. 27-33 ◽

Cited By ~ 45

Author(s):

Meghna Thakur ◽

Pradip K. Chakraborti

Keyword(s):

Protein Kinases ◽

Solid Phase ◽

Morphological Changes ◽

Binding Assays ◽

Serine Threonine Kinase ◽

Threonine Kinase ◽

Peptidoglycan Biosynthesis ◽

Vitro Binding ◽

Solid Phase Binding

Eukaryotic-type serine/threonine protein kinases in bacteria have been implicated in controlling a host of cellular activities. PknA is one of eleven such protein kinases from Mycobacterium tuberculosis which regulates morphological changes associated with cell division. In the present study we provide the evidence for the ability of PknA to transphosphorylate mMurD (mycobacterial UDP-N-acetylmuramoyl-L-alanine:D-glutamate-ligase), the enzyme involved in peptidoglycan biosynthesis. Its co-expression in Escherichia coli along with PknA resulted in phosphorylation of mMurD. Consistent with these observations, results of the solid-phase binding assays revealed a high-affinity in vitro binding between the two proteins. Furthermore, overexpression of m-murD in Mycobacterium smegmatis yielded a phosphorylated protein. The results of the present study therefore point towards the possibility of mMurD being a substrate of PknA.

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SEL-5, A Serine/Threonine Kinase That Facilitates lin-12 Activity in Caenorhabditis elegans

Genetics ◽

10.1093/genetics/153.4.1641 ◽

1999 ◽

Vol 153 (4) ◽

pp. 1641-1654 ◽

Cited By ~ 1

Author(s):

Hanna Fares ◽

Iva Greenwald

Keyword(s):

Cell Fate ◽

Point Mutations ◽

Kinase Domain ◽

Terminal Region ◽

Serine Threonine Kinase ◽

Intracellular Domain ◽

Cell Fate Decisions ◽

Threonine Kinase ◽

Amino Terminal ◽

Fate Decision

Abstract Ligands present on neighboring cells activate receptors of the LIN-12/Notch family by inducing a proteolytic cleavage event that releases the intracellular domain. Mutations that appear to eliminate sel-5 activity are able to suppress constitutive activity of lin-12(d) mutations that are point mutations in the extracellular domain of LIN-12, but cannot suppress lin-12(intra), the untethered intracellular domain. These results suggest that sel-5 acts prior to or during ligand-dependent release of the intracellular domain. In addition, sel-5 suppression of lin-12(d) mutations is tissue specific: loss of sel-5 activity can suppress defects in the anchor cell/ventral uterine precursor cell fate decision and a sex myoblast/coelomocyte decision, but cannot suppress defects in two different ventral hypodermal cell fate decisions in hermaphrodites and males. sel-5 encodes at least two proteins, from alternatively spliced mRNAs, that share an amino-terminal region and differ in the carboxy-terminal region. The amino-terminal region contains the hallmarks of a serine/threonine kinase domain, which is most similar to mammalian GAK1 and yeast Pak1p.

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Evidence for Selection at thefusedLocus ofDrosophila virilis

Genetics ◽

10.1093/genetics/155.4.1701 ◽

2000 ◽

Vol 155 (4) ◽

pp. 1701-1709 ◽

Cited By ~ 3

Author(s):

Jorge Vieira ◽

Brian Charlesworth

Keyword(s):

Amino Acid ◽

Aspartic Acid ◽

Kinase Domain ◽

Drosophila Virilis ◽

Serine Threonine Kinase ◽

Threonine Kinase ◽

Usual Equilibrium ◽

Replacement Site ◽

Fused Gene ◽

Significant Linkage

AbstractThe genomic DNA sequence of a 2.4-kb region of the X-linked developmental gene fused was determined in 15 Drosophila virilis strains. One common replacement polymorphism is observed, where a negatively charged aspartic amino acid is replaced by the noncharged amino acid alanine. This replacement variant is located within the serine/threonine kinase domain of the fused gene and is present in ~50% of the sequences in our sample. Significant linkage disequilibrium is detected around this replacement site, although the fused gene is located in a region of the D. virilis X chromosome that seems to experience normal levels of recombination. In a 600-bp region around the replacement site, all eight alanine sequences are identical; of the six aspartic acid sequences, three are also identical. The occurrence of little or no variation within the aspartic acid and alanine haplotypes, coupled with the presence of several differences between them, is very unlikely under the usual equilibrium neutral model. Our results suggest that the fused alanine haplotypes have recently increased in frequency in the D. virilis population.

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Reversible ubiquitination regulates the Smad/TGF-β signalling pathway

Biochemical Society Transactions ◽

10.1042/bst0340761 ◽

2006 ◽

Vol 34 (5) ◽

pp. 761-763 ◽

Cited By ~ 40

Author(s):

S.J. Wicks ◽

T. Grocott ◽

K. Haros ◽

M. Maillard ◽

P. ten Dijke ◽

...

Keyword(s):

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Type I ◽

Serine Threonine Kinase ◽

Full Spectrum ◽

Threonine Kinase ◽

Pathological Conditions ◽

C Terminus ◽

Β Receptor ◽

Fine Tune

TGF-β (transforming growth factor-β) signals through serine/threonine kinase receptors and intracellular Smad transcription factors. An important regulatory step involves specific ubiquitination by Smurfs (Smad–ubiquitin regulatory factors), members of the HECT (homologous to E6-associated protein C-terminus) ubiquitin ligase family, which mediate the proteasomal degradation of Smads and/or receptors. Recently, we have defined a novel interaction between Smads and UCH37 (ubiquitin C-terminal hydrolase 37), a DUB (de-ubiquitinating enzyme) that could potentially counteract Smurf-mediated ubiquitination. We have demonstrated specific interactions between UCH37 and inhibitory Smad7, as well as weaker associations with Smad2 and Smad3. Importantly, Smad7 can act as an adaptor able to recruit UCH37 to the type I TGF-β receptor. Consequently, UCH37 dramatically up-regulates TGF-β-dependent gene expression by de-ubiquitinating and stabilizing the type I TGF-β receptor. Our findings suggest that competing effects of ubiquitin ligases and DUBs in complex with Smad7 can serve to fine-tune responses to TGF-βs under various physiological and pathological conditions. Studies are currently under way using activity-based HA (haemagglutinin)-tagged ubiquitin probes to identify the full spectrum of DUBs that impact on Smad/TGF-β signalling activity.

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Crystal structure of microtubule affinity-regulating kinase 4 catalytic domain in complex with a pyrazolopyrimidine inhibitor

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x15024747 ◽

2016 ◽

Vol 72 (2) ◽

pp. 129-134 ◽

Cited By ~ 22

Author(s):

John S. Sack ◽

Mian Gao ◽

Susan E. Kiefer ◽

Joseph E. Myers ◽

John A. Newitt ◽

...

Keyword(s):

Crystal Structure ◽

Catalytic Domain ◽

Neurofibrillary Tangle ◽

Binding Pocket ◽

Atp Binding ◽

Activation Loop ◽

Serine Threonine Kinase ◽

Atp Binding Site ◽

Threonine Kinase ◽

Catalytic Loop

Microtubule-associated protein/microtubule affinity-regulating kinase 4 (MARK4) is a serine/threonine kinase involved in the phosphorylation of MAP proteins that regulate microtubule dynamics. Abnormal activity of MARK4 has been proposed to contribute to neurofibrillary tangle formation in Alzheimer's disease. The crystal structure of the catalytic and ubiquitin-associated domains of MARK4 with a potent pyrazolopyrimidine inhibitor has been determined to 2.8 Å resolution with anRworkof 22.8%. The overall structure of MARK4 is similar to those of the other known MARK isoforms. The inhibitor is located in the ATP-binding site, with the pyrazolopyrimidine group interacting with the inter-lobe hinge region while the aminocyclohexane moiety interacts with the catalytic loop and the DFG motif, forcing the activation loop out of the ATP-binding pocket.

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A novel 205-kilodalton testis-specific serine/threonine protein kinase associated with microtubules of the spermatid manchette.

Molecular and Cellular Biology ◽

10.1128/mcb.13.12.7625 ◽

1993 ◽

Vol 13 (12) ◽

pp. 7625-7635 ◽

Cited By ~ 50

Author(s):

P D Walden ◽

N J Cowan

Keyword(s):

Protein Complex ◽

Catalytic Domain ◽

Signal Transduction Pathway ◽

Kinase Domain ◽

Cdna Expression Library ◽

Cdna Clones ◽

Expression Library ◽

Serine Threonine Kinase ◽

Expression Clone

To identify proteins which interact with and potentially modulate the function of microtubules during spermatogenesis, we prepared a total testis MAP (microtubule-associated protein) antiserum and used it to isolate cDNA clones from a mouse testis cDNA expression library. Antibodies affinity purified by using one expression clone recognized a 205-kDa protein, termed MAST205, which colocalizes with the spermatid manchette. Sequencing of full-length cDNA clones encoding MAST205 revealed it to be a novel serine/threonine kinase with a catalytic domain related to those of the A and C families. The testis-specific MAST205 RNA increases in abundance during prepuberal testis development, peaking at the spermatid stage. The microtubule-binding region of MAST205 occupies a central region of the molecule including the kinase domain and sequences C terminal to this domain. Binding of MAST205 to microtubules requires interaction with other MAPs, since it does not bind to MAP-free tubulin. A 75-kDa protein associated with immunoprecipitates of MAST205 from extracts of both whole testis and testis microtubules becomes phosphorylated in in vitro kinase assays. This 75-kDa substrate of the MAST205 kinase may form part of the MAST205 protein complex which binds microtubules. The MAST205 protein complex may function to link the signal transduction pathway with the organization of manchette microtubules.

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