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Topi sun haven1/7/2024 ![]() In addition to lethality, the collision between the DNA replication fork and the Top I-DNA covalent complex is responsible for G 2 cell cycle arrest, activation of NF-κB and ATR (for “AT mutated and Rad3 related”), stabilization of p53, increased accumulation of c- fos and c- jun mRNAs, and phosphorylation of Chk1 and RPA (reviewed in reference 16). Studies using CPT have demonstrated that moving DNA replication forks can process Top I-DNA covalent complexes into potentially lethal DNA lesions, which explains the S-phase-specific cytotoxicity of CPT ( 6). Because of the reversible nature of Top I-DNA covalent complexes, lethality occurs only upon their irreversible conversion to DNA strand breaks ( 17). CPT, the prototypic Top I poison, is known to block the religation reaction of Top I, resulting in accumulation of Top I-DNA covalent complexes ( 12, 23). In the complex, Top I is covalently linked to the 3′-phosphoryl end of the transient single-strand DNA break via a tyrosyl phosphate bond (reviewed in reference 17). They represent the covalent intermediates of the cleavage-religation reaction of Top I ( 12). Top I-DNA covalent complexes are reversible ( 21, 23). Despite the increasing importance of Top I-DNA covalent complexes, their repair mechanism(s) remains largely unclear. In addition to Top I-directed antitumor drugs, many DNA lesions (e.g., UV adducts, 1-β- d-arabinofuranosylcytosine-substituted DNA, benzopyrene-DNA adducts, and 8-oxo-guanine-modified DNA) are now known to trap Top I-DNA covalent complexes to form secondary DNA lesions ( 16, 22, 32). The antitumor drug camptothecin (CPT) is the first agent demonstrated to induce Top I-DNA covalent complexes, which is believed to be exclusively responsible for the antitumor activity of CPT ( 5). Rolled out nationwide in August 1972, the system is essentially quite similar to the Zip Codes of the United States or the Postcodes of the United Kingdom.Topoisomerase I (Top I)-DNA covalent complexes, more commonly referred to as TopI cleavable or cleavage complexes, represent a unique type of DNA lesion ( 12, 21, 23). This standardised postal address numbering system used by Indian Postal Services was introduced to simplify and accelerate everyday mail delivery processes. The remaining three digits of the PIN code detail the individual postal address within the respective district. There are currently nine coastal zones in Australia, comprising eight regional zones and one functional zone reserved for military use.Įvery PIN code features the same format, with the first digit communicating the respective region, the second indicating the sub-region and the third narrowing things further to the specific district of the sub-region. Not to be confused with the personal identification number referred to as a 'PIN' in other countries, PIN codes in Australia are six digits long and communicate postal/address information. In Australia, PIN is an acronym of Postal Index Number. We have listed more than lakh postal pincode in What Is a PIN Code? You can get the Pincode or area by clicking either name or Pincode. is used to find the pincode of Topi Topi area in New-South-Wales state in Australia. First two digits of the PINCODE denote the state information. Its a unique digit code alloted to various parts in the country. PIN Code is the postal Identification number used to track the area locations in Australia along with it's Topi Topi area, New-South-Wales state. This section has been very popular with one and all because of its utility. This section will cater to the needs of individuals as well as organizations who want to search for pin codes or addresses of localities across Topi Topi area in New-South-Wales state of Australia. ![]() Now you can search for the pin code of a particular area as well as search for the address of any place in Topi Topi area in New-South-Wales state of Australia country using it's pin code. To help you locate a particular pin code or area, we present to you a pin code search engine. Topi Topi area in New-South-Wales state, Australia and it is close to impossible to remember the pin code of a particular locality in a city/town or village or to locate a place using its pin code.
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