Primosome

Primosome

A primosome is a complex of seven proteins: DnaG primase, DnaB helicase, DnaC helicase assistant, DnaT, PriA, Pri B, and PriC. The primosome creates RNA primers on single stranded DNA during DNA replication. The primosome is utilized once on the leading strand of DNA and repeatedly, initiating each Okazaki fragment, on the lagging DNA strand. Initially the complex formed by PriA, PriB, and PriC binds to DNA. Then the DnaB-DnaC helicase complex attaches along with DnaT. This structure is referred to as the pre-primosome. Finally, DnaG will bind to the pre-primosome forming a complete primosome. The primosome attaches 1-10 RNA nucleotides to the single stranded DNA creating a DNA-RNA hybrid. This sequence of RNA is used as a primer to initiate DNA polymerase III. The RNA bases are ultimately replaced with DNA bases by RNase H nuclease, DNA polymerase I, and DNA Ligase.


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  • primosome — primosome. См. праймосома. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Primosome — Un primosome est un complexe bi enzymatique intervenant lors de la réplication de l ADN des cellules procaryotes. Il résulte de l assemblage de deux enzymes, la topoisomérase et la primase. Le primosome permet de synthétiser les amorces d ARN… …   Wikipédia en Français

  • primosome — Complex of proteins involved in the synthesis of the RNA primer sequences used in DNA replication. Main components are primase and DNA helicase that move as a unit with the replication fork …   Dictionary of molecular biology

  • primosome — noun A complex of proteins required for the initiation of bacterial DNA synthesis …   Wiktionary

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  • primosome — A protein replication complex that catalyses the initiation of synthesis of Okazaki fragments during discontinuous replication of DNA. It involves DNA primase and DNA helicase activities …   Glossary of Biotechnology

  • праймосома — primosome праймосома. Kомплекс ферментов, обеспечивающих синтез запаздывающей цепи в репликативной вилке <replication fork> посредством образования фрагментов Оказаки <Okazaki fragments>; один из основных ферментов П. ДНК праймаза… …   Молекулярная биология и генетика. Толковый словарь.

  • Primase — DNA primase is an enzyme involved in the replication of DNA. Primase catalyzes the synthesis of a short RNA (or DNA in some organisms [1]) segment called a primer complementary to a ssDNA template. Primase is of key importance in DNA replication… …   Wikipedia

  • List of genetics-related topics — This is a list of terms related to genetics. NOTOC # * 3 end * 5 end A * Acentric chromosome * Achondroplasia * Active site * Adam s Curse * Adaptation * Adenine * Adenosine * Adenovirus * Adenosine diphosphate (ADP) * Ala * Alagille syndrome *… …   Wikipedia

  • List of genetic engineering topics — NOTOC # 3 end 5 end A Acentric chromosome Achondroplasia Active site Adam s Curse Adaptation Adenine Adenosine Adenosine diphosphate Adenovirus ADP Ala Alagille syndrome Albino Alcoholism Alkylating agent Allele Allele frequency Alleles… …   Wikipedia

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