Identification of a Protein Kinase from Dictyosteliumwith Homology to the Novel Catalytic Domain of Myosin Heavy Chain Kinase A

Clancy, Colleen E.; Mendoza, Manual G.; Naismith, Teresa V.; Kolman, Michael F.; Egelhoff, Thomas

doi:10.1074/jbc.272.18.11812

Cited by 46 publications

(56 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The D. discoideum genome data base was searched using MHCK B catalytic domain sequence (Clancy et al, 1997), and as a result, a DNA sequence (contig 4260) carrying a similar catalytic domain sequence was identified. The open reading frame (ORF) of the new gene was predicted using the DNAStar software package, and primers were designed for PCR amplification of full-length cDNA.…”

Section: Cloning Of Vwka Cdnamentioning

confidence: 99%

“…Molecular cloning and biochemical characterization studies demonstrated that at least three Dictyostelium ␣-kinases genes encode enzymes that can specifically phosphorylate myosin II heavy chain (MHC) in vitro and in vivo, and were thus named as MHC kinase A (MHCK A), MHC kinase B (MHCK B) and MHC kinase C (MHCK C) (Futey et al, 1995;Clancy et al, 1997;Luo et al, 2001;Liang et al, 2002;Rico and Egelhoff, 2003). Although there are many open questions regarding the upstream regulation of Dictyostelium MHCKs, it is generally established that these enzymes play a direct role in myosin II phosphorylation and regulation of myosin II assembly dynamics in this organism (de la Roche et al, 2002).…”

Section: Introductionmentioning

confidence: 99%

“…One major class of unconventional protein kinases was first identified via representatives of myosin heavy chain kinases (MHCKs) in Dictyostelium discoideum (Futey et al, 1995;Côté et al, 1997) and via identification of mammalian eEF-2 kinase (eEF-2K) as an unconventional protein kinase (Ryazanov et al, 1997). This novel, conserved group of unconventional eukaryotic protein kinases has been termed the ␣-kinase family (Ryazanov et al, 1999;Drennan and Ryazanov, 2004).Molecular cloning and biochemical characterization studies demonstrated that at least three Dictyostelium ␣-kinases genes encode enzymes that can specifically phosphorylate myosin II heavy chain (MHC) in vitro and in vivo, and were thus named as MHC kinase A (MHCK A), MHC kinase B (MHCK B) and MHC kinase C (MHCK C) (Futey et al, 1995;Clancy et al, 1997;Luo et al, 2001;Liang et al, 2002;Rico and Egelhoff, 2003). Although there are many open questions regarding the upstream regulation of Dictyostelium MHCKs, it is generally established that these enzymes play a direct role in myosin II phosphorylation and regulation of myosin II assembly dynamics in this organism (de la Roche et al, 2002).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Identification and Characterization of a Novel α-Kinase with a von Willebrand Factor A-like Motif Localized to the Contractile Vacuole and Golgi Complex inDictyostelium discoideum

Betapudi

Mason

Licate

et al. 2005

MBoC

Self Cite

View full text Add to dashboard Cite

We have identified a new protein kinase in Dictyostelium discoideum that carries the same conserved class of "␣-kinase" catalytic domain as reported previously in myosin heavy chain kinases (MHCKs) in this amoeba but that has a completely novel domain organization. The protein contains an N-terminal von Willebrand factor A (vWFA)-like motif and is therefore named VwkA. Manipulation of VwkA expression level via high copy number plasmids (VwkA ؉؉ cells) or gene disruption (vwkA null cells) results in an array of cellular defects, including impaired growth and multinucleation in suspension culture, impaired development, and alterations in myosin II abundance and assembly. Despite sequence similarity to MHCKs, the purified protein failed to phosphorylate myosin II in vitro. Autophosphorylation activity, however, was enhanced by calcium/calmodulin, and the enzyme can be precipitated from cellular lysates with calmodulin-agarose, suggesting that VwkA may directly bind calmodulin. VwkA is cytosolic in distribution but enriched on the membranes of the contractile vacuole and Golgi-like structures in the cell. We propose that VwkA likely acts indirectly to influence myosin II abundance and assembly behavior and possibly has broader roles than previously characterized ␣ kinases in this organism, which all seem to be MHCKs. INTRODUCTIONNearly all aspects of cell life are regulated by protein phosphorylation involving a large number of biochemical reactions and distinct signaling pathways. Existence of ϳ500 genes encoding various protein kinases in the human genome further underscores their importance in cell life (Manning et al., 2002). Most of these conventional protein kinases belong to serine/threonine/tyrosine, a kinase superfamily whose members carry a conserved catalytic domain with recognizable sequence similarity in spite of having different targets in the cell (Hardie, 1994;Hanks and Hunter, 1995). In recent years, however, biochemical and molecular approaches have led to the identification of more divergent classes of eukaryotic protein kinases carrying a catalytic domain sequence with no sequence similarity with conventional protein kinase catalytic domains (Manning et al., 2002). One major class of unconventional protein kinases was first identified via representatives of myosin heavy chain kinases (MHCKs) in Dictyostelium discoideum (Futey et al., 1995;Côté et al., 1997) and via identification of mammalian eEF-2 kinase (eEF-2K) as an unconventional protein kinase (Ryazanov et al., 1997). This novel, conserved group of unconventional eukaryotic protein kinases has been termed the ␣-kinase family (Ryazanov et al., 1999;Drennan and Ryazanov, 2004).Molecular cloning and biochemical characterization studies demonstrated that at least three Dictyostelium ␣-kinases genes encode enzymes that can specifically phosphorylate myosin II heavy chain (MHC) in vitro and in vivo, and were thus named as MHC kinase A (MHCK A), MHC kinase B (MHCK B) and MHC kinase C (MHCK C) (Futey et al., 1995;Clancy et al., 1997;Luo et al., 200...

show abstract

Section: Cloning Of Vwka Cdnamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Identification and Characterization of a Novel α-Kinase with a von Willebrand Factor A-like Motif Localized to the Contractile Vacuole and Golgi Complex inDictyostelium discoideum

Betapudi

Mason

Licate

et al. 2005

MBoC

Self Cite

View full text Add to dashboard Cite

show abstract

“…A structurally related kinase, MHCK B, has been identified and cloned from Dictyostelium via sequence homology to the catalytic domain of MHCK A. Although native MHCK B has not yet been purified, a bacterially expressed truncation of MHCK B phosphorylates MHC preferentially at the mapped regulatory sites discussed above (16). Another Dictyostelium homologue of MHCK A that has been identified by cDNA and genomic sequencing has been named MHCK C, although it has not yet been characterized at the protein level (GenBank TM accession number AF079447).…”

mentioning

confidence: 99%

WD Repeat Domains Target Dictyostelium Myosin Heavy Chain Kinases by Binding Directly to Myosin Filaments

Steimle

Naismith²,

Licate

et al. 2001

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Myosin heavy chain kinase (MHCK) A phosphorylates mapped sites at the C-terminal tail of Dictyostelium myosin II heavy chain, driving disassembly of myosin filaments both in vitro and in vivo. MHCK A is organized into three functional domains that include an N-terminal coiled-coil region, a central kinase catalytic domain unrelated to conventional protein kinases, and a WD repeat domain at the C terminus. MHCK B is a homologue of MHCK A that possesses structurally related catalytic and WD repeat domains. In the current study, we explored the role of the WD repeat domains in defining the activities of both MHCK A and MHCK B using recombinant bacterially expressed truncations of these kinases either with or without their WD repeat domains. We demonstrate that substrate targeting is a conserved function of the WD repeat domains of both MHCK A and MHCK B and that this targeting is specific for Dictyostelium myosin II filaments. We also show that the mechanism of targeting involves direct binding of the WD repeat domains to the myosin substrate. To our knowledge, this is the first report of WD repeat domains physically targeting attached kinase domains to their substrates. The examples presented here may serve as a paradigm for enzyme targeting in other systems.

show abstract

“…Despite their number and essential roles in a number of events, only a few CaMBPs have been characterized fully in Dictyostelium. Myosin heavy chain kinase, a Ca 2ϩ /CaM-dependent enzyme involved in myosin assembly, has been shown to be integral in cell motility (27,28). Myosin I isoforms are Ca 2ϩ -independent CaM targets (17).…”

mentioning

confidence: 99%

Nucleomorphin

Myre

O’Day

2002

Journal of Biological Chemistry

View full text Add to dashboard Cite

Probing of Dictyostelium discoideum cell extracts after SDS-PAGE using 35 . The open reading frame of 1119 nucleotides encodes a polypeptide of 340 amino acids with a calculated molecular mass of 38.7 kDa and is constitutively expressed throughout the Dictyostelium life cycle. Nucleomorphin contains a highly acidic glutamic/aspartic acid inverted repeat (DEED) with significant similarity to the conserved nucleoplasmin domain and a putative transmembrane domain in the carboxyl-terminal region. Southern blotting reveals that nucleomorphin exists as a single copy gene. Using gel overlay assays and CaM-agarose we show that bacterially expressed nucleomorphin binds to bovine CaM in a Ca 2؉ -dependent manner. Amino-terminal fusion to the green fluorescence protein (GFP) showed that GFP-NumA localized to the nucleus as distinct arc-like patterns similar to heterochromatin regions. GFP-NumA lacking the acidic DEED repeat still showed arc-like accumulations at the nuclear periphery, but the number of nuclei in these cells was increased markedly compared with control cells. Cells expressing GFP-NumA lacking the transmembrane domain localized to the nuclear periphery but did not affect nuclear number or gross morphology. Nucleomorphin is the first nuclear CaMBP to be identified in Dictyostelium. Furthermore, these data present the first identification of a member of the nucleoplasmin family as a calmodulin-binding protein and suggest nucleomorphin has a role in nuclear structure in Dictyostelium.

show abstract

Identification of a Protein Kinase from Dictyosteliumwith Homology to the Novel Catalytic Domain of Myosin Heavy Chain Kinase A

Cited by 46 publications

References 16 publications

Identification and Characterization of a Novel α-Kinase with a von Willebrand Factor A-like Motif Localized to the Contractile Vacuole and Golgi Complex inDictyostelium discoideum

Identification and Characterization of a Novel α-Kinase with a von Willebrand Factor A-like Motif Localized to the Contractile Vacuole and Golgi Complex inDictyostelium discoideum

WD Repeat Domains Target Dictyostelium Myosin Heavy Chain Kinases by Binding Directly to Myosin Filaments

Nucleomorphin

Contact Info

Product

Resources

About