Is ATM used in NHEJ?

Is ATM used in NHEJ?

As V(D)J recombination is essentially normal in ataxia-telangiectasia cells, and as the loss of ATM does not lead to defective DSBs, repair to the extent seen in DNA-PKcs-deficient or Ku-deficient cells, ATM was not considered significant in NHEJ.

How do you inhibit NHEJ?

Small molecule inhibitors of NHEJ can abrogate binding of proteins to DNA break site. Treatment of SCR7 or SCR7-pyrazine abrogates Ligase IV function, thereby inhibiting NHEJ. Repair balance is now tipped towards HR, leading to increased precision. L755507 and RS-1 may also be used to increase HDR frequency.

What is double strand break resection?

In all the eukaryotic cells, nucleolytic processing (resection) of a double strand DNA break (DSB) is a key step to channel the repair of the lesion toward the homologous recombination, at the expenses of the non-homologous end joining (NHEJ).

What is the difference between HDR and NHEJ?

HDR is a precise repair mechanism that uses homologous donor DNA to repair DNA damage, whereas NHEJ is an error-prone mechanism in which broken ends of DNA are joined together, often resulting in a heterogeneous pool of insertions and deletions.

What is ATM in cell cycle?

ATM serine/threonine kinase, symbol ATM, is a serine/threonine protein kinase that is recruited and activated by DNA double-strand breaks. It phosphorylates several key proteins that initiate activation of the DNA damage checkpoint, leading to cell cycle arrest, DNA repair or apoptosis.

What cellular mechanisms fix double-strand breaks?

DNA double-strand breaks are repaired by means of two main mechanisms: nonhomologous end joining and homologous recombination (see Figure 1). Both mechanisms operate in all eukaryotic cells that have been examined but the relative contribution of each mechanism varies.

How is NHEJ used in CRISPR?

NHEJ can also be engaged by variants of the canonical Cas9 approach. A pair of CRISPR guides that flank regions of hundreds of base pairs or more can simultaneously introduce a pair of chromosome breaks, and could result in deletion of the intervening DNA (“pop-out” deletions) if NHEJ joins the distal ends together.

What are indels in NHEJ?

NHEJ is the major DSB repair mechanism since it takes place in both dividing and nondividing cells. NHEJ can be error prone when re-ligating the free ends, so small insertions or deletions (indels) are often made at the lesion site.