P81947 · TBA1B_BOVIN
- ProteinTubulin alpha-1B chain
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids451 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
Tubulin is the major constituent of microtubules, a cylinder consisting of laterally associated linear protofilaments composed of alpha- and beta-tubulin heterodimers (PubMed:2207090, PubMed:6504138, PubMed:7704569).
Microtubules grow by the addition of GTP-tubulin dimers to the microtubule end, where a stabilizing cap forms. Below the cap, tubulin dimers are in GDP-bound state, owing to GTPase activity of alpha-tubulin (PubMed:2207090, PubMed:6504138, PubMed:7704569).
Microtubules grow by the addition of GTP-tubulin dimers to the microtubule end, where a stabilizing cap forms. Below the cap, tubulin dimers are in GDP-bound state, owing to GTPase activity of alpha-tubulin (PubMed:2207090, PubMed:6504138, PubMed:7704569).
Catalytic activity
- GTP + H2O = GDP + H+ + phosphateThis reaction proceeds in the forward direction.
Cofactor
Features
Showing features for binding site, active site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 11 | GTP (UniProtKB | ChEBI) | ||||
Sequence: Q | ||||||
Binding site | 71 | GTP (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 71 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: E | ||||||
Binding site | 140 | GTP (UniProtKB | ChEBI) | ||||
Sequence: S | ||||||
Binding site | 144 | GTP (UniProtKB | ChEBI) | ||||
Sequence: G | ||||||
Binding site | 145 | GTP (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 179 | GTP (UniProtKB | ChEBI) | ||||
Sequence: T | ||||||
Binding site | 206 | GTP (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 228 | GTP (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Active site | 254 | |||||
Sequence: E | ||||||
Site | 451 | Involved in polymerization | ||||
Sequence: Y |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | cytoplasm | |
Cellular Component | cytosol | |
Cellular Component | microtubule | |
Cellular Component | microtubule cytoskeleton | |
Molecular Function | GTP binding | |
Molecular Function | GTPase activity | |
Molecular Function | metal ion binding | |
Molecular Function | structural constituent of cytoskeleton | |
Biological Process | microtubule cytoskeleton organization | |
Biological Process | mitotic cell cycle |
Keywords
- Molecular function
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameTubulin alpha-1B chain
- EC number
- Alternative names
- Cleaved into 1 chains
Organism names
- Organism
- Strain
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Laurasiatheria > Artiodactyla > Ruminantia > Pecora > Bovidae > Bovinae > Bos
Accessions
- Primary accessionP81947
- Secondary accessions
Proteomes
Subcellular Location
PTM/Processing
Features
Showing features for chain, modified residue, cross-link.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000437397 | 1-450 | Detyrosinated tubulin alpha-1B chain | |||
Sequence: MRECISIHVGQAGVQIGNACWELYCLEHGIQPDGQMPSDKTIGGGDDSFNTFFSETGAGKHVPRAVFVDLEPTVIDEVRTGTYRQLFHPEQLITGKEDAANNYARGHYTIGKEIIDLVLDRIRKLADQCTGLQGFLVFHSFGGGTGSGFTSLLMERLSVDYGKKSKLEFSIYPAPQVSTAVVEPYNSILTTHTTLEHSDCAFMVDNEAIYDICRRNLDIERPTYTNLNRLISQIVSSITASLRFDGALNVDLTEFQTNLVPYPRIHFPLATYAPVISAEKAYHEQLSVAEITNACFEPANQMVKCDPRHGKYMACCLLYRGDVVPKDVNAAIATIKTKRSIQFVDWCPTGFKVGINYQPPTVVPGGDLAKVQRAVCMLSNTTAIAEAWARLDHKFDLMYAKRAFVHWYVGEGMEEGEFSEAREDMAALEKDYEEVGVDSVEGEGEEEGEE | ||||||
Chain | PRO_0000048114 | 1-451 | Tubulin alpha-1B chain | |||
Sequence: MRECISIHVGQAGVQIGNACWELYCLEHGIQPDGQMPSDKTIGGGDDSFNTFFSETGAGKHVPRAVFVDLEPTVIDEVRTGTYRQLFHPEQLITGKEDAANNYARGHYTIGKEIIDLVLDRIRKLADQCTGLQGFLVFHSFGGGTGSGFTSLLMERLSVDYGKKSKLEFSIYPAPQVSTAVVEPYNSILTTHTTLEHSDCAFMVDNEAIYDICRRNLDIERPTYTNLNRLISQIVSSITASLRFDGALNVDLTEFQTNLVPYPRIHFPLATYAPVISAEKAYHEQLSVAEITNACFEPANQMVKCDPRHGKYMACCLLYRGDVVPKDVNAAIATIKTKRSIQFVDWCPTGFKVGINYQPPTVVPGGDLAKVQRAVCMLSNTTAIAEAWARLDHKFDLMYAKRAFVHWYVGEGMEEGEFSEAREDMAALEKDYEEVGVDSVEGEGEEEGEEY | ||||||
Modified residue | 40 | N6,N6,N6-trimethyllysine; alternate | ||||
Sequence: K | ||||||
Modified residue | 40 | N6-acetyllysine; alternate | ||||
Sequence: K | ||||||
Modified residue | 48 | Phosphoserine | ||||
Sequence: S | ||||||
Modified residue | 232 | Phosphoserine | ||||
Sequence: S | ||||||
Modified residue | 282 | 3'-nitrotyrosine | ||||
Sequence: Y | ||||||
Cross-link | 326 | Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin) | ||||
Sequence: K | ||||||
Modified residue | 339 | Omega-N-methylarginine | ||||
Sequence: R | ||||||
Cross-link | 370 | Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin) | ||||
Sequence: K | ||||||
Modified residue | 439 | Phosphoserine | ||||
Sequence: S | ||||||
Modified residue | 443 | 5-glutamyl polyglutamate | ||||
Sequence: E | ||||||
Modified residue | 445 | 5-glutamyl polyglutamate | ||||
Sequence: E | ||||||
Modified residue | 451 | 3'-nitrotyrosine | ||||
Sequence: Y |
Post-translational modification
Some glutamate residues at the C-terminus are polyglycylated, resulting in polyglycine chains on the gamma-carboxyl group. Glycylation is mainly limited to tubulin incorporated into axonemes (cilia and flagella) whereas glutamylation is prevalent in neuronal cells, centrioles, axonemes, and the mitotic spindle. Both modifications can coexist on the same protein on adjacent residues, and lowering polyglycylation levels increases polyglutamylation, and reciprocally. Cilia and flagella glycylation is required for their stability and maintenance. Flagella glycylation controls sperm motility.
Some glutamate residues at the C-terminus are polyglutamylated, resulting in polyglutamate chains on the gamma-carboxyl group (By similarity).
Polyglutamylation plays a key role in microtubule severing by spastin (SPAST). SPAST preferentially recognizes and acts on microtubules decorated with short polyglutamate tails: severing activity by SPAST increases as the number of glutamates per tubulin rises from one to eight, but decreases beyond this glutamylation threshold (By similarity).
Glutamylation is also involved in cilia motility (By similarity).
Polyglutamylation plays a key role in microtubule severing by spastin (SPAST). SPAST preferentially recognizes and acts on microtubules decorated with short polyglutamate tails: severing activity by SPAST increases as the number of glutamates per tubulin rises from one to eight, but decreases beyond this glutamylation threshold (By similarity).
Glutamylation is also involved in cilia motility (By similarity).
Acetylation of alpha chains at Lys-40 is located inside the microtubule lumen. This modification has been correlated with increased microtubule stability, intracellular transport and ciliary assembly.
Methylation of alpha chains at Lys-40 is found in mitotic microtubules and is required for normal mitosis and cytokinesis contributing to genomic stability.
Nitration of Tyr-451 is irreversible and interferes with normal dynein intracellular distribution.
Undergoes a tyrosination/detyrosination cycle, the cyclic removal and re-addition of a C-terminal tyrosine residue by the enzymes tubulin tyrosine carboxypeptidase (MATCAP, VASH1 or VASH2) and tubulin tyrosine ligase (TTL), respectively.
Tubulin alpha-1B chain
Tyrosination promotes microtubule interaction with CAP-Gly domain-containing proteins such as CLIP1, CLIP2 and DCTN1 (By similarity).
Tyrosination regulates the initiation of dynein-dynactin motility via interaction with DCTN1, which brings the dynein-dynactin complex into contact with microtubules. In neurons, tyrosinated tubulins mediate the initiation of retrograde vesicle transport (By similarity).
Tyrosination regulates the initiation of dynein-dynactin motility via interaction with DCTN1, which brings the dynein-dynactin complex into contact with microtubules. In neurons, tyrosinated tubulins mediate the initiation of retrograde vesicle transport (By similarity).
Detyrosinated tubulin alpha-1B chain
Detyrosination is involved in metaphase plate congression by guiding chromosomes during mitosis: detyrosination promotes interaction with CENPE, promoting pole-proximal transport of chromosomes toward the equator (By similarity).
Detyrosination increases microtubules-dependent mechanotransduction in dystrophic cardiac and skeletal muscle. In cardiomyocytes, detyrosinated microtubules are required to resist to contractile compression during contraction: detyrosination promotes association with desmin (DES) at force-generating sarcomeres, leading to buckled microtubules and mechanical resistance to contraction (By similarity).
Detyrosination increases microtubules-dependent mechanotransduction in dystrophic cardiac and skeletal muscle. In cardiomyocytes, detyrosinated microtubules are required to resist to contractile compression during contraction: detyrosination promotes association with desmin (DES) at force-generating sarcomeres, leading to buckled microtubules and mechanical resistance to contraction (By similarity).
Keywords
- PTM
Proteomic databases
PTM databases
Interaction
Subunit
Dimer of alpha and beta chains (PubMed:2207090, PubMed:6504138, PubMed:7704569).
A typical microtubule is a hollow water-filled tube with an outer diameter of 25 nm and an inner diameter of 15 nM. Alpha-beta heterodimers associate head-to-tail to form protofilaments running lengthwise along the microtubule wall with the beta-tubulin subunit facing the microtubule plus end conferring a structural polarity. Microtubules usually have 13 protofilaments but different protofilament numbers can be found in some organisms and specialized cells
A typical microtubule is a hollow water-filled tube with an outer diameter of 25 nm and an inner diameter of 15 nM. Alpha-beta heterodimers associate head-to-tail to form protofilaments running lengthwise along the microtubule wall with the beta-tubulin subunit facing the microtubule plus end conferring a structural polarity. Microtubules usually have 13 protofilaments but different protofilament numbers can be found in some organisms and specialized cells
Protein-protein interaction databases
Structure
Family & Domains
Features
Showing features for region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Region | 432-451 | Disordered | ||||
Sequence: YEEVGVDSVEGEGEEEGEEY |
Sequence similarities
Belongs to the tubulin family.
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length451
- Mass (Da)50,152
- Last updated2009-02-10 v2
- Checksum94355B4EC2086429
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
BC146060 EMBL· GenBank· DDBJ | AAI46061.1 EMBL· GenBank· DDBJ | mRNA |