The modification of a histone by the addition of an acetyl group.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

Any process that results in the specification, formation or maintenance of the physical structure of eukaryotic chromatin.

The modification of a histone by the addition of an acetyl group.

The modification of a histone by the addition of an acetyl group.

Any process that activates or increases the frequency, rate or extent of transcription elongation, the extension of an RNA molecule after transcription initiation and promoter clearance by the addition of ribonucleotides, catalyzed by RNA polymerase II.

Any process that activates or increases the frequency, rate or extent of transcription elongation, the extension of an RNA molecule after transcription initiation and promoter clearance by the addition of ribonucleotides, catalyzed by RNA polymerase II.

The modification of histone H3 by the addition of an acetyl group.

The process whose specific outcome is the progression of the heart over time, from its formation to the mature structure. The heart is a hollow, muscular organ, which, by contracting rhythmically, keeps up the circulation of the blood.

The process whose specific outcome is the progression of a limb over time, from its formation to the mature structure. A limb is an appendage of an animal used for locomotion or grasping. Examples include legs, arms or some types of fin.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

The addition of an acetyl group to a protein amino acid. An acetyl group is CH3CO-, derived from acetic

The addition of an acetyl group to a non-terminal lysine residue in a protein.

Any process that activates or increases the frequency, rate or extent of gluconeogenesis by activating or increasing the frequency, rate or extent of transcription from an RNA polymerase II promoter.

The modification of histone H3 by the addition of an acetyl group.

The modification of histone H3 by the addition of an acetyl group to a lysine residue at position 14 of the histone.

Any process that activates or increases the frequency, rate or extent of transcription from an RNA polymerase II promoter.

Any process that stops, prevents, or reduces the frequency, rate or extent of centriole replication.

Any process that stops, prevents, or reduces the frequency, rate or extent of centriole replication.

The appearance of a cytokine due to biosynthesis or secretion following a cellular stimulus, resulting in an increase in its intracellular or extracellular levels.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

Any process that modulates the frequency, rate or extent of cellular DNA-templated transcription.

Any process that modulates the frequency, rate or extent of cellular DNA-templated transcription.

The addition of an acetyl group to a protein amino acid. An acetyl group is CH3CO-, derived from acetic

The process whose specific outcome is the progression of the heart over time, from its formation to the mature structure. The heart is a hollow, muscular organ, which, by contracting rhythmically, keeps up the circulation of the blood.

The memory process that deals with the storage, retrieval and modification of information a long time (typically weeks, months or years) after receiving that information. This type of memory is typically dependent on gene transcription regulated by second messenger activation.

Any process that stops, prevents or reduces the rate or extent of cell proliferation.

Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a light stimulus, electromagnetic radiation of wavelengths classified as infrared, visible or ultraviolet light.

The process whose specific outcome is the progression of the flower over time, from its formation to the mature structure. The flower is the reproductive structure in a plant, and its development begins with the transition of the vegetative or inflorescence meristem into a floral meristem.

The process in which the anatomical structures of roots are generated and organized. The root is the usually underground part of a seed plant body that originates from the hypocotyl, functions as an organ of absorption, aeration, and food storage or as a means of anchorage and support.

Any process that modulates the frequency, rate or extent of vegetative phase change. Vegetative phase change is the set of post-embryonic processes involved in the transition of a plant from a juvenile phase of vegetative development to an adult phase of vegetative development.

Any process that modulates the frequency, rate or extent of protein ADP-ribosylation. Protein ADP-ribosylation is the transfer, from NAD, of ADP-ribose to protein amino acids.

Any process that increases the rate, frequency or extent of neuron projection development. Neuron projection development is the process whose specific outcome is the progression of a neuron projection over time, from its formation to the mature structure. A neuron projection is any process extending from a neural cell, such as axons or dendrites (collectively called neurites).

The removal of one or more ubiquitin groups from a protein.

The acetylation of the N-terminal lysine of proteins.

The addition of an acetyl group to a non-terminal lysine residue in a protein.

The addition of an acetyl group to a non-terminal lysine residue in a protein.

The addition of an acetyl group to a non-terminal lysine residue in a protein.

The acetylation of peptidyl-lysine.

Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of an insulin stimulus. Insulin is a polypeptide hormone produced by the islets of Langerhans of the pancreas in mammals, and by the homologous organs of other organisms.

Any process that increases the frequency, rate or extent of chromatin binding. Chromatin binding is the selective interaction with chromatin, the network of fibers of DNA, protein, and sometimes RNA, that make up the chromosomes of the eukaryotic nucleus during interphase.

The modification of histone H4 by the addition of an acetyl group.

The modification of histone H3 by the addition of an acetyl group to a lysine residue at position 9 of the histone.

The modification of histone H3 by the addition of an acetyl group to a lysine residue at position 9 of the histone.

Any process that modulates the frequency, rate or extent of differentiation of regulatory T cells.

Any process that stops, prevents, or reduces the frequency, rate or extent of cyclin-dependent protein serine/threonine kinase activity.

Any epigenetic process that activates or increases the rate of gene expression.

Any process that activates or increases the frequency, rate or extent of cellular DNA-templated transcription.

Any process that activates or increases the frequency, rate or extent of cellular DNA-templated transcription.

Any process that activates or increases the frequency, rate or extent of transcription from an RNA polymerase II promoter.

Any process that activates or increases the frequency, rate or extent of transcription from an RNA polymerase II promoter.

Any process that stops, prevents, or reduces the frequency, rate or extent of centriole replication.

A process that modulates synaptic plasticity, the ability of synapses to change as circumstances require. They may alter function, such as increasing or decreasing their sensitivity, or they may increase or decrease in actual numbers.

Any process that modulates the frequency, rate or extent of T cell activation.

The process whose specific outcome is the progression of a limb over time, from its formation to the mature structure. A limb is an appendage of an animal used for locomotion or grasping. Examples include legs, arms or some types of fin.

The process in which bones are generated and organized.

Any process that activates or increases the frequency, rate or extent of the addition of an acetyl group to histone H3 at position 14 of the histone.

Any process that increases the diameter of blood vessels.

The modification of a histone by the addition of an succinyl group.

Any process that activates or increases the frequency, rate or extent of wax biosynthetic process.

Any process that activates or increases the frequency, rate or extent of wax biosynthetic process.

Any process that activates or increases the frequency, rate or extent of histone H3-K9 acetylation.

The process whose specific outcome is the progression of the embryo in the uterus over time, from formation of the zygote in the oviduct, to birth. An example of this process is found in Mus musculus.

The formation of mesodermal clusters that are arranged segmentally along the anterior posterior axis of an embryo.

The formation of mesodermal clusters that are arranged segmentally along the anterior posterior axis of an embryo.

The appearance of a cytokine due to biosynthesis or secretion following a cellular stimulus, resulting in an increase in its intracellular or extracellular levels.

The last step in the formation of the neural tube, where the paired neural folds are brought together and fuse at the dorsal midline.

Any process that results in the specification, formation or maintenance of the physical structure of eukaryotic chromatin.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

Dynamic structural changes to eukaryotic chromatin occurring throughout the cell division cycle. These changes range from the local changes necessary for transcriptional regulation to global changes necessary for chromosome segregation.

Any process that modulates the frequency, rate or extent of transcription mediated by RNA polymerase II.

Any process that modulates the frequency, rate or extent of transcription mediated by RNA polymerase II.

Any process that modulates the frequency, rate or extent of transcription mediated by RNA polymerase II.

Any process involved in the assembly of the RNA polymerase II preinitiation complex (PIC) at an RNA polymerase II promoter region of a DNA template, resulting in the subsequent synthesis of RNA from that promoter. The initiation phase includes PIC assembly and the formation of the first few bonds in the RNA chain, including abortive initiation, which occurs when the first few nucleotides are repeatedly synthesized and then released. Promoter clearance, or release, is the transition between the initiation and elongation phases of transcription.

The addition of an acetyl group to a protein amino acid. An acetyl group is CH3CO-, derived from acetic

A regulatory process that halts progression through the cell cycle during one of the normal phases (G1, S, G2, M).

The cell cycle process in which double strand breaks are formed and repaired through a double Holliday junction intermediate. This results in the equal exchange of genetic material between non-sister chromatids in a pair of homologous chromosomes. These reciprocal recombinant products ensure the proper segregation of homologous chromosomes during meiosis I and create genetic diversity.

A series of molecular signals initiated by the binding of an extracellular ligand to the receptor Notch on the surface of a target cell, and ending with regulation of a downstream cellular process, e.g. transcription.

The activation of transcription of specific genes as a result of Notch signaling, mediated by the Notch intracellular domain.

The process whose specific outcome is the progression of nervous tissue over time, from its formation to its mature state.

The memory process that deals with the storage, retrieval and modification of information a long time (typically weeks, months or years) after receiving that information. This type of memory is typically dependent on gene transcription regulated by second messenger activation.

The multiplication or reproduction of cells, resulting in the expansion of a cell population.

Any process that stops, prevents or reduces the rate or extent of cell proliferation.

The set of specific processes that generate the ability of an organism to induce an abnormal, generally detrimental state in another organism.

Any process that stops, prevents, or reduces the frequency or rate of initiation of conjugation with cellular fusion.

Any process that modulates the frequency, rate or extent of protein ADP-ribosylation. Protein ADP-ribosylation is the transfer, from NAD, of ADP-ribose to protein amino acids.

Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of an organic cyclic compound stimulus.

The modification of a histone by the addition of an acetyl group.

The modification of histones by removal of ubiquitin groups.

The modification of histones by removal of ubiquitin groups.

The acetylation of the N-terminal lysine of proteins.

The acetylation of peptidyl-lysine.

The process whose specific outcome is the progression of the telencephalon over time, from its formation to the mature structure. The telencephalon is the paired anteriolateral division of the prosencephalon plus the lamina terminalis from which the olfactory lobes, cerebral cortex, and subcortical nuclei are derived.

The process whose specific outcome is the progression of the metencephalon over time, from its formation to the mature structure.

The process whose specific outcome is the progression of the midbrain over time, from its formation to the mature structure. The midbrain is the middle division of the three primary divisions of the developing chordate brain or the corresponding part of the adult brain (in vertebrates, includes a ventral part containing the cerebral peduncles and a dorsal tectum containing the corpora quadrigemina and that surrounds the aqueduct of Sylvius connecting the third and fourth ventricles).

Any process that activates or increases the frequency, rate or extent of the process involved in the formation, arrangement of constituent parts, or disassembly of cell projections.

Any process that activates or increases the frequency, rate or extent of the process involved in the formation, arrangement of constituent parts, or disassembly of cell projections.

A process that is carried out at the cellular level which results in the assembly, arrangement of constituent parts, or disassembly of the fungal-type cell wall.

Any process that affects the structure and integrity of a protein, altering the likelihood of its degradation or aggregation.

Any process that affects the structure and integrity of a protein, altering the likelihood of its degradation or aggregation.

Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a stimulus reflecting the presence, absence, or concentration of nutrients.

Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of an insulin stimulus. Insulin is a polypeptide hormone produced by the islets of Langerhans of the pancreas in mammals, and by the homologous organs of other organisms.

Any process that activates or increases the frequency, rate or extent of the addition of an acetyl group to a histone protein.

Any process that activates or increases the frequency, rate or extent of the addition of an acetyl group to a histone protein.

The increase in size or mass of an entire multicellular organism, as opposed to cell growth.

Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a drug stimulus. A drug is a substance used in the diagnosis, treatment or prevention of a disease.

The modification of histone H3 by the addition of an acetyl group.

The modification of histone H3 by the addition of an acetyl group.

The modification of histone H4 by the addition of an acetyl group to a lysine residue at position 12 of the histone.

The process in which a group of unicellular organisms grow in a threadlike, filamentous shape.

Any process that modulates the frequency, rate or extent of differentiation of regulatory T cells.

Any process that modulates the frequency, rate or extent of megakaryocyte differentiation.

Any process that activates or increases the frequency, rate or extent of the Notch signaling pathway.

Any process that activates or increases the frequency, rate or extent of transcription from an RNA polymerase II promoter.

Any process that activates or increases the frequency, rate or extent of transcription from an RNA polymerase II promoter.

A process that modulates synaptic plasticity, the ability of synapses to change as circumstances require. They may alter function, such as increasing or decreasing their sensitivity, or they may increase or decrease in actual numbers.

Any process that establishes the spatial arrangement of mitochondria within the cell.

Any process that establishes the spatial arrangement of mitochondria within the cell.

Any process that modulates the frequency, rate or extent of T cell activation.

Any process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a tumor necrosis factor stimulus.

The addition of an acetyl group to the lysine 40 residue of alpha-tubulin.

The addition of an acetyl group to the lysine 40 residue of alpha-tubulin.

The modification of a histone by the addition of an succinyl group.

The modification of a histone by the addition of an succinyl group.

A negative regulation of transcription from RNA polymerase II promoter that results in negative regulation of induction of conjugation with cellular fusion.

Any process that stops, prevents or reduces the frequency, rate or extent of leucine import across plasma membrane.

A process that results in a change in state or activity of a cell (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a nerve growth factor stimulus.

Any process that activates or increases the frequency, rate or extent of cardiac muscle cell differentiation.

Any process that activates or increases the frequency, rate or extent of cardiac muscle cell differentiation.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A multiprotein complex that possesses histone acetyltransferase and is involved in regulation of transcription. Contains either GCN5 or PCAF in a mutually exclusive manner. The budding yeast complex includes Gcn5p, two proteins of the Ada family, and two TBP-associate proteins (TAFs); analogous complexes in other species have analogous compositions, and usually contain homologs of the yeast proteins. Both ATAC- or SAGA (see GO:0000124, SAGA complex) are involved in the acetylation of histone H3K9 and K14 residues.

A SAGA-type histone acetyltransferase complex that contains Spt8 (in budding yeast) or a homolog thereof; additional polypeptides include Spt group, consisting of Spt7, Spt3, and Spt20/Ada5, which interact with the TATA-binding protein (TBP); the Ada group, consisting of Ada1, Ada2, Ada3, Ada4/Gcn5, and Ada5/Spt20, which is functionally linked to the nucleosomal HAT activity; Tra1, an ATM/PI-3 kinase-related protein that targets DNA-bound activators for recruitment to promoters; the TBP-associated factor (TAF) proteins, consisting of Taf5, Taf6, Taf9, Taf10, and Taf12, which mediate nucleosomal HAT activity and are thought to help recruit the basal transcription machinery; the ubiquitin specifc protease Ubp-8.

The part of the cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.

The region of a chromosome that includes the centromeric DNA and associated proteins. In monocentric chromosomes, this region corresponds to a single area of the chromosome, whereas in holocentric chromosomes, it is evenly distributed along the chromosome.

A SAGA-type histone acetyltransferase complex that contains Rtg2 and a smaller form of Spt7 than the fungal SAGA complex, and lacks Spt8. The complex is involved in the yeast retrograde response pathway, which is important for gene expression changes during mitochondrial dysfunction.

That part of the nuclear content other than the chromosomes or the nucleolus.

A structure comprised of a core structure (in most organisms, a pair of centrioles) and peripheral material from which a microtubule-based structure, such as a spindle apparatus, is organized. Centrosomes occur close to the nucleus during interphase in many eukaryotic cells, though in animal cells it changes continually during the cell-division cycle.

A protein complex that possesses histone acetyltransferase activity.

The ordered and organized complex of DNA, protein, and sometimes RNA, that forms the chromosome in the nucleus.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A multiprotein complex that possesses histone acetyltransferase and is involved in regulation of transcription. Contains either GCN5 or PCAF in a mutually exclusive manner. The budding yeast complex includes Gcn5p, two proteins of the Ada family, and two TBP-associate proteins (TAFs); analogous complexes in other species have analogous compositions, and usually contain homologs of the yeast proteins. Both ATAC- or SAGA (see GO:0000124, SAGA complex) are involved in the acetylation of histone H3K9 and K14 residues.

A structure comprised of a core structure (in most organisms, a pair of centrioles) and peripheral material from which a microtubule-based structure, such as a spindle apparatus, is organized. Centrosomes occur close to the nucleus during interphase in many eukaryotic cells, though in animal cells it changes continually during the cell-division cycle.

A protein complex that possesses histone acetyltransferase activity.

A multisubunit complex that is located at the centromeric region of DNA and provides an attachment point for the spindle microtubules.

The ordered and organized complex of DNA, protein, and sometimes RNA, that forms the chromosome in the nucleus.

A type of chromosome in a polyploid cell, formed when multiple copies of homologous chromosomes are aligned side by side to give a giant chromosome in which distinct chromosome bands are readily visible.

A swelling at a site along the length of a polytene chromosome, thought to be the site of active transcription.

A structure comprised of a core structure (in most organisms, a pair of centrioles) and peripheral material from which a microtubule-based structure, such as a spindle apparatus, is organized. Centrosomes occur close to the nucleus during interphase in many eukaryotic cells, though in animal cells it changes continually during the cell-division cycle.

The part of the cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.

A large multiprotein complex that possesses histone acetyltransferase and is involved in regulation of transcription. The composition is similar to that of the SAGA complex; for example, the human complex contains the transcription-transformation cofactor TRRAP, hGCN5L acetylase, novel human ADA-like and SPT-like cofactors, and a subset of TAFs.

The dark-staining region of a sarcomere, in which myosin thick filaments are present; the center is traversed by the paler H zone, which in turn contains the M line.

A region of a sarcomere that appears as a light band on each side of the Z disc, comprising a region of the sarcomere where thin (actin) filaments are not overlapped by thick (myosin) filaments; contains actin, troponin, and tropomyosin; each sarcomere includes half of an I band at each end.

A stable assembly of two or more macromolecules, i.e. proteins, nucleic acids, carbohydrates or lipids, in which at least one component is a protein and the constituent parts function together.

Any complex of actin, myosin, and accessory proteins.

A protein complex that possesses histone acetyltransferase activity.

A SAGA-type histone acetyltransferase complex that contains Spt8 (in budding yeast) or a homolog thereof; additional polypeptides include Spt group, consisting of Spt7, Spt3, and Spt20/Ada5, which interact with the TATA-binding protein (TBP); the Ada group, consisting of Ada1, Ada2, Ada3, Ada4/Gcn5, and Ada5/Spt20, which is functionally linked to the nucleosomal HAT activity; Tra1, an ATM/PI-3 kinase-related protein that targets DNA-bound activators for recruitment to promoters; the TBP-associated factor (TAF) proteins, consisting of Taf5, Taf6, Taf9, Taf10, and Taf12, which mediate nucleosomal HAT activity and are thought to help recruit the basal transcription machinery; the ubiquitin specifc protease Ubp-8.

A SAGA-type histone acetyltransferase complex that contains Spt8 (in budding yeast) or a homolog thereof; additional polypeptides include Spt group, consisting of Spt7, Spt3, and Spt20/Ada5, which interact with the TATA-binding protein (TBP); the Ada group, consisting of Ada1, Ada2, Ada3, Ada4/Gcn5, and Ada5/Spt20, which is functionally linked to the nucleosomal HAT activity; Tra1, an ATM/PI-3 kinase-related protein that targets DNA-bound activators for recruitment to promoters; the TBP-associated factor (TAF) proteins, consisting of Taf5, Taf6, Taf9, Taf10, and Taf12, which mediate nucleosomal HAT activity and are thought to help recruit the basal transcription machinery; the ubiquitin specifc protease Ubp-8.

A large multiprotein complex that possesses histone acetyltransferase activity and is involved in regulation of transcription. The composition is similar to that of the SAGA complex, but includes fewer Spt and Ada proteins, and more TAFs.

That part of a multicellular organism outside the cells proper, usually taken to be outside the plasma membranes, and occupied by fluid.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

A multiprotein complex that possesses histone acetyltransferase and is involved in regulation of transcription. Contains either GCN5 or PCAF in a mutually exclusive manner. The budding yeast complex includes Gcn5p, two proteins of the Ada family, and two TBP-associate proteins (TAFs); analogous complexes in other species have analogous compositions, and usually contain homologs of the yeast proteins. Both ATAC- or SAGA (see GO:0000124, SAGA complex) are involved in the acetylation of histone H3K9 and K14 residues.

A large multiprotein complex that possesses histone acetyltransferase and is involved in regulation of transcription. The composition is similar to that of the SAGA complex; for example, the human complex contains the transcription-transformation cofactor TRRAP, hGCN5L acetylase, novel human ADA-like and SPT-like cofactors, and a subset of TAFs.

A stable assembly of two or more macromolecules, i.e. proteins, nucleic acids, carbohydrates or lipids, in which at least one component is a protein and the constituent parts function together.

A stable assembly of two or more macromolecules, i.e. proteins, nucleic acids, carbohydrates or lipids, in which at least one component is a protein and the constituent parts function together.

A protein complex that does not contain either a TATA-binding protein (TBP) or a TBP-like factor, but is composed of several TAFIIs and other proteins, including a histone acetyltransferase. This complex is able to nucleate transcription initiation by RNA polymerase II, can mediate transcriptional activation, and has histone acetyltransferase activity.

A protein complex that does not contain either a TATA-binding protein (TBP) or a TBP-like factor, but is composed of several TAFIIs and other proteins, including a histone acetyltransferase. This complex is able to nucleate transcription initiation by RNA polymerase II, can mediate transcriptional activation, and has histone acetyltransferase activity.

A multisubunit complex that catalyzes the acetylation of histone H3.

A spindle that forms as part of mitosis. Mitotic and meiotic spindles contain distinctive complements of proteins associated with microtubules.