The expression of thymidine kinase in fungi, which normally lack this enzyme, will greatly aid the study of DNA metabolism and provide useful drug-sensitive phenotypes. The herpes simplex virus type-1 thymidine kinase gene ( tk ) was expressed in Neurospora crassa. tk was expressed as a fusion to N.crassa arg-2 regulatory sequences and as a hygromycin phosphotransferase-thymidine kinase fusion ...

A thymidine kinase (EC 2.7.1.21) associated with mitochondria has been demonstrated in tissue culture both in wild type mouse cells and in cells which lack the cytoplasmic thymidine kinase. The mitochondrial thymidine kinase represents approximately 1% of the total cell thymidine kinase activity in wild type cells grown in culture and all of the activity of the mutant cells. The mitochondrial e...

The structural gene for herpes simplex virus (type 1) thymidine kinase was cloned downstream from the X phage high efficiency leftward promotor in a plasmid (pHETK2) also containing the gene for the X cI857 temperature-sensitive repressor. Thymidine kinase is synthesized as a run-on product containing the NH2 terminus of the X N protein. Heat inactivation of the X repressor by growth at 42 O C ...

Thymidine kinase is a cell cycle-dependent marker that can be detected in the serum of patients diagnosed with many different types of cancer. Serum levels of thymidine kinase have also been shown to reflect the progression of cancer as well as an indication of the efficacy of chemotherapeutic intervention. A new monoclonal antibody assay for thymidine kinase has been developed, which is capabl...

We have constructed a recombinant adenovirus that carries the herpes simplex virus type I gene for thymidine kinase (EC 2.7.1.21) and expresses thymidine kinase under control of adenovirus major late promoter. A DNA fragment carrying thymidine kinase coding sequences but lacking the thymidine kinase promoter was sandwiched between a piece of adenoviral DNA and simian virus 40 early DNA on a pla...

It has become increasingly apparent that t,hymidine kinase (ATP: thymidine 5’-phosphotransferase, EC 2.7.1.21) is a site of specific regulatory control of the levels of uracil and thymine deoxyribonucleotides within cells (1, 2). The synthesis of thymidine kinase is subject to control by repression (3, 4) and the activity of the enzyme can be strikingly inhibited by thymidine triphosphate (end ...