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At least 19 recordsLinked to original sources
PubMed1993

Calmodulin binding to and cAMP-dependent phosphorylation of kinesin light chains modulate kinesin ATPase activity.

Kinesin is an ubiquitous heterotetrameric microtubule-based motor which translocates membrane-bound organelles. Since organelle motility and motor protein function can be regulated by components of signaling pathways, the ability of purified bovine brain kinesin (kinesin) to be phosphorylated and to recognize calmodulin (CaM) was tested. Extensively purified "kinesin" was found to consist of several forms of both heavy (KHC) and light (KLC) chains. Phosphorylation of kinesin by a variety of protein kinases was examined; cAMP-dependent protein kinase (cAMP-PK) was the most active enzyme leading to the incorporation of up to 8 mol P/mol kinesin. Phosphorylation occurred predominantly on the KLCs and led to substantial acidic pI shifts. Peptide maps indicated that multiple phosphorylation sites exist on each KLC. Incubation of kinesin in vitro with protein kinase C (PKC) led to the phosphorylation of both KHCs and KLCs. In vivo phosphorylation of KHC and KLCs was demonstrated by immunoprecipitation of [32P]-labeled kinesin from cultured rat hippocampal pyramidal neurons; kinesin phosphorylation was stimulated by 8-chlorophenyl-thio-cAMP or 12-O-tetradecanoylphorbol-13-acetate. Native bovine brain kinesin was shown to bind 125I-CaM by nucleotide-dependent pelleting with stable microtubules. Specific calcium-dependent binding of 125I-CaM to KLCs but not KHC was found using a ligand blotting assay. cAMP-PK phosphorylated kinesin bound 125I-CaM less well than untreated protein in both ligand blotting and microtubule-pelleting paradigms. Calcium-dependent binding of CaM to kinesin inhibited the ATPase activity of native kinesin but not of cAMP-PK phosphorylated kinesin. These results suggest that the KLCs have a regulatory function and integrate information coming from diverse signaling pathways to modulate the activity and function of kinesin.

Adenosine Triphosphatases↗
PubMed2003

The Drosophila kinesin-I associated protein YETI binds both kinesin subunits.

The microtubule-based motor kinesin-I is essential for the intracellular transport of membrane-bound organelles in the Drosophila nervous system and female germ line. A number of studies have demonstrated that kinesin-I binds to its intracellular cargos through protein-protein interactions between the kinesin tail domain and proteins on the cargo surface. To identify proteins that mediate or regulate kinesin-cargo interactions, we have performed yeast two-hybrid screens of a Drosophila embryonic cDNA library, using the tetratricopeptide repeats of the kinesin light chain and amino acids 675-975 of the kinesin heavy chain as baits. One of the proteins we have identified is YETI. Interestingly, YETI has the unique ability to bind specifically to both subunits of the kinesin tail domain. An epitope-tagged YETI fusion protein, when expressed in Drosophila S2 cultured cells, binds to kinesin-I in copurification assays, suggesting that YETI-kinesin-I interactions are context-independent. Immunostaining of cultured cells expressing YETI shows that YETI accumulates in the nucleus and cytosol. YETI is evolutionarily conserved, and its yeast homolog (AOR1) may have a role in regulating cytoskeletal dynamics or intracellular transport. Collectively, these results demonstrate that YETI interacts with both kinesin subunits of the kinesin tail domain, and is potentially involved in kinesin-dependent transport pathways.

Amino Acid Sequence↗
PubMed1998

Kinesin is a candidate for cross-bridging microtubules and intermediate filaments. Selective binding of kinesin to detyrosinated tubulin and vimentin.

We showed previously that stable, detyrosinated (Glu) microtubules function to localize vimentin intermediate filaments in fibroblasts (Gurland, G., and Gundersen, G. G. (1995) J. Cell Biol. 131, 1275-1290). To identify candidate proteins that mediate the Glu microtubule-vimentin interaction, we incubated microtubules with microtubule-interacting proteins and saturating levels of antibodies to Glu or tyrosinated (Tyr) tubulin. Antibodies to Glu tubulin prevented the microtubule binding of kinesin obtained from fibroblast or brain extracts more effectively than antibodies to Tyr tubulin. Scatchard plot analysis showed that kinesin heads bound to Glu microtubules with an approximately 2.8-fold higher affinity than to Tyr microtubules. Purified brain kinesin cosedimented with vimentin, but not with neurofilaments, indicating that kinesin specifically associates with vimentin without accessory molecules. Kinesin binding to vimentin was not sensitive to ATP, and kinesin heads failed to bind to vimentin. By SDS-polyacrylamide gel electrophoresis, a kinesin heavy chain of approximately 120 kDa and a light chain of approximately 64 kDa were detected in vimentin/kinesin pellets. The light chain reacted with a general kinesin light chain antibody, but not with two other antibodies that recognize the two known isoforms of kinesin light chain in brain, suggesting that the kinesin involved in binding to vimentin may be a specific one. These results demonstrate a kinesin-based mechanism for the preferential interaction of vimentin with detyrosinated microtubules.

3T3 Cells↗
PubMed1995

Fast axonal transport of kinesin in the rat visual system: functionality of kinesin heavy chain isoforms.

The mechanochemical ATPase kinesin is thought to move membrane-bounded organelles along microtubules in fast axonal transport. However, fast transport includes several classes of organelles moving at rates that differ by an order of magnitude. Further, the fact that cytoplasmic forms of kinesin exist suggests that kinesins might move cytoplasmic structures such as the cytoskeleton. To define cellular roles for kinesin, the axonal transport of kinesin was characterized. Retinal proteins were pulse-labeled, and movement of radiolabeled kinesin through optic nerve and tract into the terminals was monitored by immunoprecipitation. Heavy and light chains of kinesin appeared in nerve and tract at times consistent with fast transport. Little or no kinesin moved with slow axonal transport indicating that effectively all axonal kinesin is associated with membranous organelles. Both kinesin heavy chain molecular weight variants of 130,000 and 124,000 M(r) (KHC-A and KHC-B) moved in fast anterograde transport, but KHC-A moved at 5-6 times the rate of KHC-B. KHC-A cotransported with the synaptic vesicle marker synaptophysin, while a portion of KHC-B cotransported with the mitochondrial marker hexokinase. These results suggest that KHC-A is enriched on small tubulovesicular structures like synaptic vesicles and that at least one form of KHC-B is predominantly on mitochondria. Biochemical specialization may target kinesins to appropriate organelles and facilitate differential regulation of transport.

Animals↗
PubMed2005

Myosin-V, Kinesin-1, and Kinesin-3 cooperate in hyphal growth of the fungus Ustilago maydis.

Long-distance transport is crucial for polar-growing cells, such as neurons and fungal hyphae. Kinesins and myosins participate in this process, but their functional interplay is poorly understood. Here, we investigate the role of kinesin motors in hyphal growth of the plant pathogen Ustilago maydis. Although the microtubule plus-ends are directed to the hyphal tip, of all 10 kinesins analyzed, only conventional kinesin (Kinesin-1) and Unc104/Kif1A-like kinesin (Kinesin-3) were up-regulated in hyphae and they are essential for extended hyphal growth. deltakin1 and deltakin3 mutant hyphae grew irregular and remained short, but they were still able to grow polarized. No additional phenotype was detected in deltakin1rkin3 double mutants, but polarity was lost in deltamyo5rkin1 and deltamyo5rkin3 mutant cells, suggesting that kinesins and class V myosin cooperate in hyphal growth. Consistent with such a role in secretion, fusion proteins of green fluorescent protein and Kinesin-1, Myosin-V, and Kinesin-3 accumulate in the apex of hyphae, a region where secretory vesicles cluster to form the fungal Spitzenkörper. Quantitative assays revealed a role of Kin3 in secretion of acid phosphatase, whereas Kin1 was not involved. Our data demonstrate that just two kinesins and at least one myosin support hyphal growth.

Cell Polarity↗
PubMedDate not supplied

Universal and unique features of kinesin motors: insights from a comparison of fungal and animal conventional kinesins.

Kinesins are microtubule motors that use the energy derived from the hydrolysis of ATP to move unidirectionally along microtubules. The founding member of this still growing superfamily is conventional kinesin, a dimeric motor that moves processively towards the plus end of microtubules. Within the family of conventional kinesins, two groups can be distinguished to date, one derived from animal species, and one originating from filamentous fungi. So far no conventional kinesin has been reported from plant cells. Fungal and animal conventional kinesins differ in several respects, both in terms of their primary sequence and their physiological properties. Thus all fungal conventional kinesins move at velocities that are 4-5 times higher than those of animal conventional kinesins, and all of them appear to lack associated light chains. Both groups of motors are characterized by a number of group-specific sequence features which are considered here with respect to their functional importance. Animal and fungal conventional kinesins also share a number of sequence characteristics which point to common principles of motor function. The overall domain organization is remarkably similar. A C-terminal sequence motif common to all kinesins, which constitutes the only region of high homology outside the motor domain, suggests common principles of cargo association in both groups of motors. Consideration of the differences of, and similarities between, fungal and animal kinesins offers novel possibilities for experimentation (e. g., by constructing chimeras) that can be expected to contribute to our understanding of motor function.

Amino Acid Sequence↗
PubMed1999

Kinesin-II, the heteromeric kinesin.

The kinesins constitute a large family of motor proteins which are responsible for the distribution of numerous organelles, vesicles and macromolecular complexes throughout the cell. One class of these molecular motors, kinesin-II, is unique in that these proteins are typically found as heterotrimeric complexes containing two different, though related, kinesin-like motor subunits, and a single nonmotor subunit. The heteromeric nature of these kinesins appears to have resulted in a class of combinatorial kinesins which can 'mix and match' different motor subunits. Another novel feature of these motors is that the activities of several kinesin-II representatives are essential in the assembly of motile and nonmotile cilia, a role not attributed to any other kinesin. This review presents a brief overview of the structure and biological functions of kinesin-II, the heteromeric kinesin.

Amino Acid Sequence↗
PubMed2000

Tumor necrosis factor induces hyperphosphorylation of kinesin light chain and inhibits kinesin-mediated transport of mitochondria.

The molecular motor kinesin is an ATPase that mediates plus end-directed transport of organelles along microtubules. Although the biochemical properties of kinesin are extensively studied, conclusive data on regulation of kinesin-mediated transport are largely lacking. Previously, we showed that the proinflammatory cytokine tumor necrosis factor induces perinuclear clustering of mitochondria. Here, we show that tumor necrosis factor impairs kinesin motor activity and hyperphosphorylates kinesin light chain through activation of two putative kinesin light chain kinases. Inactivation of kinesin, hyperphosphorylation of kinesin light chain, and perinuclear clustering of mitochondria exhibit the same p38 mitogen-activated kinase dependence, indicating their functional relationship. These data provide evidence for direct regulation of kinesin-mediated organelle transport by extracellular stimuli via cytokine receptor signaling pathways.

Animals↗
PubMed2006

A "holistic" kinesin phylogeny reveals new kinesin families and predicts protein functions.

Kinesin superfamily proteins are ubiquitous to all eukaryotes and essential for several key cellular processes. With the establishment of genome sequence data for a substantial number of eukaryotes, it is now possible for the first time to analyze the complete kinesin repertoires of a diversity of organisms from most eukaryotic kingdoms. Such a "holistic" approach using 486 kinesin-like sequences from 19 eukaryotes and analyzed by Bayesian techniques, identifies three new kinesin families, two new phylum-specific groups, and unites two previously identified families. The paralogue distribution suggests that the eukaryotic cenancestor possessed nearly all kinesin families. However, multiple losses in individual lineages mean that no family is ubiquitous to all organisms and that the present day distribution reflects common biology more than it does common ancestry. In particular, the distribution of four families--Kinesin-2, -9, and the proposed new families Kinesin-16 and -17--correlates with the possession of cilia/flagella, and this can be used to predict a flagellar function for two new kinesin families. Finally, we present a set of hidden Markov models that can reliably place most new kinesin sequences into families, even when from an organism at a great evolutionary distance from those in the analysis.

Animals↗
PubMed1992

Immunolocalization of kinesin in sea urchin coelomocytes. Association of kinesin with intracellular organelles.

We have recently used domain-specific monoclonal antibodies (mAbs) to immunofluorescently localize kinesin to vesicle-like structures in the cytoplasm of sea urchin coelomocytes. In order to characterize further these localization patterns we have examined the distribution of kinesin with respect to the arrangement of microtubules (MTs) and various organelles. In double-label experiments involving the immunofluorescent staining of kinesin (using a mixture of the mAbs SUK2, 4 and 5), MTs were labeled with an antiserum against sea urchin tubulin, the endoplasmic reticulum (ER) was labeled with an antiserum against a luminal calsequestrin-like protein, the Golgi apparatus was labeled with rhodamine-wheat germ agglutinin (WGA) or NBD-ceramide, mitochondria were labeled with rhodamine 123, endosomes were labeled with Texas Red-ovalbumin, and lysosomes were labeled with Lucifer yellow or acridine orange. Kinesin-labeled vesicle-like structures were found in the same regions of the cells as MTs and the ER, being widely distributed in motile cells, but restricted to the perinuclear regions of stationary cells. There also appeared to be a correlation between the distribution of endosomes and kinesin staining in a subpopulation of cells. The kinesin binding structures were found occasionally to align in linear arrays, consistent with the idea that kinesin may transport ER and endosomes along linear MT tracks. No clear correlations were observed between the kinesin staining and the distribution of mitochondria, the Golgi apparatus or lysosomes, suggesting that kinesin may specifically associate with only a subclass of organelles in coelomocytes.

Animals↗
PubMed1998

The C-terminal region of the stalk domain of ubiquitous human kinesin heavy chain contains the binding site for kinesin light chain.

The motor protein kinesin is a heterotetramer composed of two heavy chains of approximately 120 kDa and two light chains of approximately 65 kDa protein. Kinesin motor activity is dependent on the presence of ATP and microtubules. The kinesin light chain-binding site in human kinesin heavy chain was determined by reconstituting in vitro a complex of recombinant heavy and light chains. The proteins expressed in bacteria included oligohistidine-tagged fragments of human ubiquitous kinesin heavy chain, spanning most of the stalk and all of the tail domain (amino acids 555-963); and untagged, essentially full-length human kinesin light chain (4-569) along with N-terminal (4-363) and C-terminal (364-569) light chain fragments. Heavy chain fragments were attached to Ni2+-charged beads and incubated with untagged light chain fragments. Analysis of eluted complexes by SDS-PAGE and immunoblotting mapped the light chain-binding site in heavy chain to amino acids 771-813, a region close to the C-terminal end of the heavy chain stalk domain. In addition, only the full-length and N-terminal kinesin light chain fragments bound to this heavy chain region. Within this heavy chain region are four highly conserved contiguous heptad repeats (775-802) which are predicted to form a tight alpha-helical coiled-coil interaction with the heptad repeat-containing N-terminus of the light chain, in particular region 106-152 of human light chain. This predicted hydrophobic, alpha-helical coiled-coil interaction is supported by both circular dichroism spectroscopy of the recombinant kinesin heavy chain fragment 771-963, which displays an alpha-helical content of 70%, and the resistance of the heavy/light chain interaction to high salt (0.5 M).

Amino Acid Sequence↗
PubMed2002

The calmodulin-binding domain from a plant kinesin functions as a modular domain in conferring Ca2+-calmodulin regulation to animal plus- and minus-end kinesins.

Plant kinesin-like calmodulin-binding protein (KCBP) is a novel member of the kinesin superfamily that interacts with calmodulin (CaM) via its CaM-binding domain (CBD). Activated CaM (Ca(2+)-CaM) has been shown to inhibit KCBP interaction with microtubules (MTs) thereby abolishing its motor- and MT-dependent ATPase activities. To test whether the fusion of CBD to non-CaM-binding kinesins confers Ca(2+)-CaM regulation, we fused the CBD of KCBP to the N or C terminus of a minus-end (non-claret disjunction) or C terminus of a plus-end (Drosophila kinesin) motor. Purified chimeric kinesins bound CaM in a Ca(2+)-dependent manner whereas non-claret disjunction, Drosophila kinesin, and KCBP that lack a CBD did not. As in the case of KCBP with CBD, the interaction of chimeric motors with MTs, as well as their MT-stimulated ATPase activity, was inhibited by Ca(2+)-CaM. The presence of a spacer between the motor and CBD did not alter Ca(2+)-CaM regulation. However, KCBP interaction with MTs and its MT-stimulated ATPase activity were not inhibited when the motor domain and CBD were added separately, suggesting that Ca(2+)-CaM regulation of CaM-binding motors occurs only when the CBD is attached to the motor domain. These results show that the fusion of the CBD to animal motors confers Ca(2+)-CaM regulation and suggest that the CBD functions as a modular domain in disrupting motor-MT interaction. Our data also support the hypothesis that CaM-binding kinesins may have evolved by addition of a CBD to a kinesin motor domain.

Animals↗
PubMed1997

A kinesin-like mechanoenzyme from the zygomycete Syncephalastrum racemosum shares biochemical similarities with conventional kinesin from Neurospora crassa.

The kinesin superfamily consists of mechanoenzymes that convert chemical energy, stored in nucleoside triphosphates, into movement along microtubules. The founding member of this protein superfamily, the so-called conventional kinesin, was only known from animal sources until the recent description of kinesin from the filamentous fungus Neurospora crassa (G. Steinberg, M. Schliwa, Mol. Biol. Cell 6, 1605-1618 (1995)). To determine whether similar motors with comparable features are common in other filamentous fungi, a kinesin from a zygomycete, Syncephalastrum racemosum, was purified. Here, the isolation and characterization of this motorenzyme is described. The purified protein consisted of a doublet at 112 kDa and 115 kDa with no additional polypeptides. This was consistent with a calculated molecular mass of approximately 240 kDa and suggests that the motor is a dimer with a more globular shape than conventional kinesin from animal sources. In gliding assays the enzyme moved microtubules at 2.5 to 3.4 microns/s and had a nucleotide specificity similar to the Neurospora kinesin motor. Peptide antibodies against conserved regions in the head and the tall domain of conventional kinesins cross-reacted with the Syncephalastrum motor. In vitro, the enzyme was able to drive the microtubule-dependent movement of vesicles isolated from Syncephalastrum racemosum, as well as Neurospora crassa, and Aspergillus nidulans. In summary, the Syncephalastrum motor has many of the unique features in common with the conventional kinesin from the ascomycete Neurospora crassa and probably shares a similar function in living hyphae.

Animals↗
PubMed1997

Cholinergic stimulation of lacrimal acinar cells promotes redistribution of membrane-associated kinesin and the secretory protein, beta-hexosaminidase, and increases kinesin motor activity.

The role of the microtubule-based motor, kinesin, in membrane trafficking has been investigated in resting and stimulated acinar cells from rabbit lacrimal gland, a cholinergically controlled secretory tissue. Microtubule-dependent motors from extracts of control and carbachol-treated acini were isolated by microtubule-affinity purification and their activity was determined using a video-enhanced differential interference contrast microscopy assay for microtubule gliding. The observation that carbachol treatment resulted in a 2.2-fold stimulation of the frequency of GTP-dependent microtubule gliding in fractions isolated by microtubule-affinity purification and GTP release suggested that kinesin was a target of carbachol-induced stimulation. Resolution of membranes from resting cells by fractionation on a sorbitol density gradient followed by partitioning analysis in a dextran-polyethyleneglycol two-phase system revealed that membrane-associated kinesin codistributed with Golgi-derived membranes, a post-Golgi secretory compartment designated Hex1, membranes from a trans Golgi network-like compartment, endoplasmic reticulum and a group of putative lysosomal membranes containing cathepsin B. Comparable fractionation of carbachol-treated acini showed that stimulation caused redistributions of membrane-associated kinesin, the secretory enzyme beta-hexosaminidase, and galactosyltransferase that appeared to reflect both a reorganization within the Golgi complex and a return of material to the Golgi complex from the secretory pathway. Our findings that carbachol promotes activation of lacrimal acinar kinesin as well as major shifts in kinesin-membrane association within the secretory pathway suggests that kinesin plays a major role in secretory vesicle assembly, apical secretion, and/or secretory vesicle membrane recycling in the lacrimal gland.

Animals↗
PubMed1999

Identification of kinesin-C, a calmodulin-binding carboxy-terminal kinesin in animal (Strongylocentrotus purpuratus) cells.

Several novel members of the kinesin superfamily, until now identified only in plants, are unique in their ability to bind calmodulin in the presence of Ca(2+). Here, we identify the first such kinesin in an animal system. Sequence analysis of this new motor, called kinesin-C, predicts that it is a large carboxy-terminal kinesin, 1624 amino acid residues in length, with a predicted molecular mass of 181 kDa. Kinesin-C is predicted to contain a kinesin motor domain at its carboxy terminus, linked to a segment of alpha-helical coiled-coil 950 amino acid residues long, ending with an amino-terminal proline-rich tail domain. A putative calmodulin-binding domain resides at the extreme carboxy terminus of the motor polypeptide, and recombinant kinesin-C binds to a calmodulin-affinity column in a Ca(2+)-dependent fashion. The presence of this novel calmodulin-binding motor in sea urchin embryos suggests that it plays a critical role in Ca(2+)-dependent events during early sea urchin development.

Amino Acid Sequence↗
PubMed2002

Kinesin-related genes from diplomonad, sponge, amphioxus, and cyclostomes: divergence pattern of kinesin family and evolution of giardial membrane-bounded organella.

To understand the question of whether divergence of eukaryotic genes by gene duplications and domain shufflings proceeded gradually or intermittently during evolution, we have cloned and sequenced Giardia lamblia cDNAs encoding kinesins and kinesin-related proteins and have obtained 13 kinesin-related cDNAs, some of which are likely homologs of vertebrate kinesins involved in vesicle transfer to ER, Golgi, and plasma membrane. A phylogenetic tree of the kinesin family revealed that most gene duplications that gave rise to different kinesin subfamilies with distinct functions have been completed before the earliest divergence of extant eukaryotes. This suggests that the complex endomembrane system has arisen very early in eukaryotic evolution, and the diminutive ER and Golgi apparatus recognized in the giardial cells, together with the absence of mitochondria, might be characters acquired secondarily during the evolution of parasitism. To understand the divergence pattern of the kinesin family in the lineage leading to vertebrates, seven more Unc104-related cDNAs have been cloned from sponge, amphioxus, hagfish, and lamprey. The divergence pattern of the animal Unc104/KIF1 subfamily is characterized by two active periods in gene duplication interrupted by a considerably long period of silence, instead of proceeding gradually: animals underwent extensive gene duplications before the parazoan-eumetazoan split. In the early evolution of vertebrates around the cyclostome-gnathostome split, further gene duplications occurred, by which a variety of genes with similar structures over the entire regions were generated. This pattern of divergence is similar to those of animal genes involved in cell-cell communication and developmental control.

Animals↗
PubMed1991

A model for kinesin movement from nanometer-level movements of kinesin and cytoplasmic dynein and force measurements.

Our detailed measurements of the movements of kinesin- and dynein-coated latex beads have revealed several important features of the motors which underlie basic mechanical aspects of the mechanisms of motor movements. Kinesin-coated beads will move along the paths of individual microtubule protofilaments with high fidelity and will pause at 4 nm intervals along the microtubule axis under low ATP conditions. In contrast, cytoplasmic dynein-coated beads move laterally across many protofilaments as they travel along the microtubule, without any regular pauses, suggesting that the movements of kinesin-coated beads are not an artefact of the method. These kinesin bead movements suggest a model for kinesin movement in which the two heads walk along an individual protofilament in a hand-over-hand fashion. A free head would only be able to bind to the next forward tubulin subunit on the protofilament and its binding would pull off the trailing head to start the cycle again. This model is consistent with the observed cooperativity between the heads and with the movement by single dimeric molecules. Several testable predictions of the model are that kinesin should be able to bind to both alpha and beta tubulin and that the length of the neck region of the molecule should control the off-axis motility. In this article, we describe the technology for measuring nanometer-level movements and the force generated by the kinesin molecule.

Adenosine Triphosphatases↗
PubMed1994

Regulation of kinesin activity by phosphorylation of kinesin-associated proteins.

The mechanochemical motor proteins of the kinesin and cytoplasmic dynein families play important roles in microtubule-based intracellular motility. Although movement and distribution of organelles like secretory granules, vesicles, endoplasmic reticulum, and chromosomes depend on the activity of these motor proteins, little is known about the regulation of this movement. We report here that the hyperphosphorylation of components of the kinesin complex by treatment with okadaic acid increases kinesin motor activity at least 2-fold. The stimulation was observed using both a granule motility assay and a microtubule gliding assay, indicating that phosphorylation enhances the activity of the motor itself, rather than the affinity of the motor for membrane organelles. Under stimulatory conditions, three proteins that co-purify with kinesin (with mobilities of 150, 79, and 73 kDa) are consistently hyperphosphorylated. Dephosphorylation of these proteins reduces kinesin activity to basal levels. Therefore, we conclude that kinesin motor activity is directly modulated by the phosphorylation state of kinesin-associated proteins.

Animals↗