Hibited by lactose but not sucrose, indicating that the effect is due to glycan binding by galectins. VEGFR2 More emphasis on pathways whose member genes show fold changes that phosphorylation levels in EA.hy926 cells following a 5-min stimulation with both galectins (1 mg/ml) in the absence or presence of lactose or sucrose (50 mmol/l). The data are presented as the mean +/2 SEM (* p,0.05). (TIF) Materials and Methods S(DOC)AcknowledgmentsWe thank Andrew Fleming and Young-Eun Hyun for comments on the manuscript.Author ContributionsConceived and designed the experiments: ND SS MLM CD LB IS. Performed the experiments: ND SS CM. Analyzed the data: ND MLM CD IS. Contributed reagents/materials/analysis tools: IA. Wrote the paper: ND CD LB IS.
Kinesin-like calmodulin binding protein (KCBP) is a molecular motor found in plants [1]. KCBP is active during different stages of mitosis [2,3]. However, its activation and silencing is crucial mainly for normal trichome morphogenesis [4]. Both mitosis and trichome morphogenesis, though discrete processes, rely on correct cytoskeleton structure, which is based on microtubules and actin filaments. In vitro, active KCBP promotes formation of microtubule bundles while its negative regulation promotes dissociation of microtubule bundles [5]. KCBP belongs to the kinesin family of molecular motors. Molecular motors of this family use the energy of ATP hydrolysis to drive a mechanical power stroke, leading to their directional movement along microtubules [6]. KCBP has a typical kinesin motor domain 18204824 often referred 1315463 to as a head. This domain attaches to microtubules and contains a functional nucleotide-binding site. However, KCBP has an unusual N-terminal tail domain that relates KCBP to another family of molecular motors, myosins, which move along actin filaments. Just like the tails of myosins VIIa and X, the tail of KCBP contains talin-like FERM domains and MyTH4 homology regions with additional affinity to microtubules [7] (Fig. 1).The motor head of KCBP is found near the C-terminus of its polypeptide chain. This structural organization places KCBP in the Kinesin-14 group of the kinesin family, together with its structural relatives, Drosophila ncd, yeast KAR3, and others [8]. Molecular motors of the Kinesin-14 group move toward the minus end of the microtubule, which has alpha subunits of tubulin exposed. KCBP has been reported to move at ,8 mm/min [9], a velocity comparable to that of ncd (,10 mm/min) [10]. A coiled coil is predicted to form functional Title Loaded From File dimers of KCBP (Fig. 1) using a segment a.a. 749?55. This dimerization domain precedes the motor head within the protein sequence [11]. KCBP has another unusual structural domain that distinguishes it among kinesins, at the very C-terminus of the polypeptide chain. The C-terminal regulatory domain of KCBP consists of three structural features coil-helix-coil. These features are termed the neck mimic, regulatory helix, and negative coil, respectively [12]. Two of these features, the regulatory helix and the neck mimic, have been previously characterized. The regulatory helix is recognized independently by calmodulin and additionally by a specific KCBP regulator, the Ca2+ ion sensor KIC [13]. KIC is a specialized calmodulin with just two Ca2+ ion coordinating EF hands, one of them being disabled by mutations, instead of four EF hands present in calmodulin. When bound to KCBP, these Ca2+binding proteins cause the motor to detach from microtubules andDimerization of KCBP at C-TerminusFigure 1. Schematic presentation of the domai.Hibited by lactose but not sucrose, indicating that the effect is due to glycan binding by galectins. VEGFR2 phosphorylation levels in EA.hy926 cells following a 5-min stimulation with both galectins (1 mg/ml) in the absence or presence of lactose or sucrose (50 mmol/l). The data are presented as the mean +/2 SEM (* p,0.05). (TIF) Materials and Methods S(DOC)AcknowledgmentsWe thank Andrew Fleming and Young-Eun Hyun for comments on the manuscript.Author ContributionsConceived and designed the experiments: ND SS MLM CD LB IS. Performed the experiments: ND SS CM. Analyzed the data: ND MLM CD IS. Contributed reagents/materials/analysis tools: IA. Wrote the paper: ND CD LB IS.
Kinesin-like calmodulin binding protein (KCBP) is a molecular motor found in plants [1]. KCBP is active during different stages of mitosis [2,3]. However, its activation and silencing is crucial mainly for normal trichome morphogenesis [4]. Both mitosis and trichome morphogenesis, though discrete processes, rely on correct cytoskeleton structure, which is based on microtubules and actin filaments. In vitro, active KCBP promotes formation of microtubule bundles while its negative regulation promotes dissociation of microtubule bundles [5]. KCBP belongs to the kinesin family of molecular motors. Molecular motors of this family use the energy of ATP hydrolysis to drive a mechanical power stroke, leading to their directional movement along microtubules [6]. KCBP has a typical kinesin motor domain 18204824 often referred 1315463 to as a head. This domain attaches to microtubules and contains a functional nucleotide-binding site. However, KCBP has an unusual N-terminal tail domain that relates KCBP to another family of molecular motors, myosins, which move along actin filaments. Just like the tails of myosins VIIa and X, the tail of KCBP contains talin-like FERM domains and MyTH4 homology regions with additional affinity to microtubules [7] (Fig. 1).The motor head of KCBP is found near the C-terminus of its polypeptide chain. This structural organization places KCBP in the Kinesin-14 group of the kinesin family, together with its structural relatives, Drosophila ncd, yeast KAR3, and others [8]. Molecular motors of the Kinesin-14 group move toward the minus end of the microtubule, which has alpha subunits of tubulin exposed. KCBP has been reported to move at ,8 mm/min [9], a velocity comparable to that of ncd (,10 mm/min) [10]. A coiled coil is predicted to form functional dimers of KCBP (Fig. 1) using a segment a.a. 749?55. This dimerization domain precedes the motor head within the protein sequence [11]. KCBP has another unusual structural domain that distinguishes it among kinesins, at the very C-terminus of the polypeptide chain. The C-terminal regulatory domain of KCBP consists of three structural features coil-helix-coil. These features are termed the neck mimic, regulatory helix, and negative coil, respectively [12]. Two of these features, the regulatory helix and the neck mimic, have been previously characterized. The regulatory helix is recognized independently by calmodulin and additionally by a specific KCBP regulator, the Ca2+ ion sensor KIC [13]. KIC is a specialized calmodulin with just two Ca2+ ion coordinating EF hands, one of them being disabled by mutations, instead of four EF hands present in calmodulin. When bound to KCBP, these Ca2+binding proteins cause the motor to detach from microtubules andDimerization of KCBP at C-TerminusFigure 1. Schematic presentation of the domai.
