TEN1 Human

TEN1 is a human full-length protein, typically expressed in Escherichia coli for recombinant purposes. The protein consists of 123 amino acids and is often tagged with a His tag at the N-terminus for purification and identification purposes . The recombinant form of TEN1 is highly purified, with a purity level exceeding 90%, making it suitable for various biochemical assays such as SDS-PAGE and mass spectrometry .

TEN1, along with CTC1 and STN1, forms the CST complex, which binds to single-stranded DNA with high affinity. This binding is crucial for protecting telomeres from degradation and inappropriate recombination. The CST complex is involved in several aspects of telomere replication, including:

1. Telomerase Inhibition: The CST complex binds to newly synthesized 3’ overhangs by telomerase, terminating its action and maintaining telomere length homeostasis .
2. Fill-in Synthesis: The CST complex recruits and activates DNA polymerase alpha, facilitating the synthesis of the telomeric C-strand .

TEN1 is essential for telomere stability. Mutations in TEN1 can lead to severe telomere dysfunction, resulting in developmental defects and a constitutive DNA damage response. For instance, a point mutation in the TEN1 gene (mdo1-1/ten1-3) in Arabidopsis thaliana causes severe shoot apical meristem aberrations, including stem cell death or differentiation . This mutation also leads to shorter and more heterogeneous telomere tracts, frequent telomere fusions, and increased single-strand telomeric DNA .

Recombinant TEN1 is widely used in research to study telomere biology and the mechanisms underlying telomere maintenance. Its high purity and specific activity make it a valuable tool for biochemical assays and structural studies. Understanding the function and regulation of TEN1 can provide insights into telomere-related diseases and potential therapeutic targets.