TUBG1 Human, Sf9
Description
Introduction to TUBG1 Human, Sf9
TUBG1 Human, Sf9 refers to the recombinant human γ-tubulin isoform 1 (TUBG1) produced in Spodoptera frugiperda (Sf9) insect cells. This protein is a critical component of the γ-tubulin ring complex (γ-TuRC), which nucleates microtubules and regulates mitotic spindle assembly. With a molecular mass of 51.9 kDa and 457 amino acids, TUBG1 is glycosylated and includes a C-terminal 6-amino acid His tag for purification .
Functional Roles in Microtubule Biology
3.1 Microtubule Nucleation
TUBG1 forms the core of γ-TuRC, which templates microtubule assembly. Recombinant γ-TuRC reconstituted from insect cells recapitulates native nucleation activity, facilitating minus-end capping and structural stability .
3.2 Structural Insights
Cryo-EM studies reveal TUBG1’s role in the γ-TuRC’s left-handed spiral architecture. The complex includes:
-
14 γ-tubulin subunits arranged in a helical array.
-
GCP2–GCP6 proteins stabilizing the γ-tubulin lattice.
3.3 Post-Translational Modifications
TUBG1 undergoes phosphorylation (e.g., at S51, S146, T238, S397, T400) and ubiquitination, regulating its localization and activity. For example:
-
Monoubiquitination by BRCA1/BARD1 displaces γ-TuRC from centrosomes.
Research Applications and Experimental Findings
4.1 In Vitro Microtubule Nucleation Assays
Recombinant TUBG1-containing γ-TuRC demonstrates nucleation activity comparable to native complexes. Addition of CM1 domain proteins (e.g., CDK5RAP2) enhances activity by 7.1-fold in human γ-TuRC .
4.2 Self-Assembly and Filament Formation
At concentrations ≥0.25 μM, purified TUBG1 forms helical arrays with 5-fold symmetry. These arrays promote αβ-tubulin polymerization, reducing kinetic barriers to microtubule assembly .
4.3 Therapeutic Targeting in Cancer
While not a therapeutic compound itself, TUBG1 is a target for inhibitors like L12 in RB1-deficient tumors. L12 selectively disrupts TUBG1-mediated RB1 suppression, enhancing E2F1-dependent apoptosis without affecting TUBG2 (a brain-specific isoform) .
Product Specs
Tubulin gamma-1 chain, Gamma-1-tubulin, Gamma-tubulin complex component 1, GCP-1, TUBG1, TUBG, Tubulin, Gamma 1, Gamma-1-Tubulin, TUBGCP1, CDCBM4.
Sf9, Insect cells.
MPREIITLQL GQCGNQIGFE FWKQLCAEHG ISPEGIVEEF ATEGTDRKDV FFYQADDEHY IPRAVLLDLE PRVIHSILNS PYAKLYNPEN IYLSEHGGGA GNNWASGFSQ GEKIHEDIFD IIDREADGSD SLEGFVLCHS IAGGTGSGLG SYLLERLNDR YPKKLVQTYS VFPNQDEMSD VVVQPYNSLL TLKRLTQNAD CVVVLDNTAL NRIATDRLHI QNPSFSQINQ LVSTIMSAST TTLRYPGYMN NDLIGLIASL IPTPRLHFLM TGYTPLTTDQ SVASVRKTTV LDVMRRLLQP KNVMVSTGRD RQTNHCYIAI LNIIQGEVDP TQVHKSLQRI RERKLANFIP WGPASIQVAL SRKSPYLPSA HRVSGLMMAN HTSISSLFER TCRQYDKLRK REAFLEQFRK EDMFKDNFDE MDTSREIVQQ LIDEYHAATR PDYISWGTQE QHHHHHH.
Product Science Overview
Tubulin Gamma 1 (TUBG1) is a member of the tubulin superfamily, which plays a crucial role in the nucleation and organization of microtubules. Microtubules are essential components of the cytoskeleton, involved in various cellular processes such as cell division, intracellular transport, and maintenance of cell shape. TUBG1 is specifically involved in the formation of the gamma-tubulin ring complex (γ-TuRC), which is critical for microtubule nucleation at the centrosome .
TUBG1 produced in Sf9 insect cells is a recombinant protein that consists of a single, glycosylated polypeptide chain containing 457 amino acids. It has a molecular mass of approximately 51.9 kDa. The recombinant protein is expressed with a 6-amino acid His tag at the C-terminus, which facilitates its purification using chromatographic techniques .
TUBG1 localizes to the centrosome and binds to microtubules to form the γ-TuRC. This complex is essential for the nucleation of microtubules, which is the initial step in microtubule formation. The γ-TuRC acts as a template for the addition of α- and β-tubulin dimers, leading to the polymerization of microtubules. TUBG1 is also involved in the progression of the cell cycle, as it ensures the proper formation and function of the mitotic spindle during cell division .
Recombinant TUBG1 produced in Sf9 insect cells is widely used in research to study the mechanisms of microtubule nucleation and organization. It is also used to investigate the role of γ-tubulin in various cellular processes, including cell division and intracellular transport. Additionally, TUBG1 can be used as a tool to identify and characterize proteins that interact with the γ-TuRC .
The recombinant TUBG1 protein is provided as a sterile, filtered, colorless solution. It is formulated in a buffer containing 20 mM Tris-HCl (pH 8.0), 40% glycerol, 0.1 M NaCl, 2 mM DTT, and 50 mM imidazole. For short-term storage, the protein can be kept at 4°C for 2-4 weeks. For long-term storage, it is recommended to store the protein at -20°C with the addition of a carrier protein such as 0.1% HSA or BSA to prevent degradation. It is important to avoid multiple freeze-thaw cycles to maintain the protein’s stability .
