About the author Ana

APLF and long non-coding RNA NIHCOLE promote stable DNA synapsis in non-homologous end joining

Here, we show that Ku70-Ku80 and APLF establish a minimal complex sufficient to support DNA synapsis. APLF and long non-coding RNA NIHCOLE promote stable DNA synapsis in non-homologous end joining. Additionally, we show how APLF promotes synapsis of DNA ends for several minutes under pN forces and lncRNA NIHCOLE stabilises these synapsis via a small and structured domain relevant in DNA repair by NHEJ.

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Human HELB is a processive motor protein which catalyses RPA clearance from single-stranded DNA

Here, we characterize the biochemical activities of the human DNA helicase B (HELB) using bulk and single-molecule methods.
We found that HELB is a monomeric protein that binds to ssDNA with a site size of 20nt, unexpectedly large for SF1 helicases, suggesting an additional binding site.
HELB binds specifically to human RPA, which enhances its ATPase and ssDNA translocase activities.
Translocating HELB concomitantly clears RPA from ssDNA.

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Purified Smc5/6 Complex Exhibits DNA Substrate Recognition and Compaction

Eukaryotic SMC complexes, cohesin, condensin, and Smc5/6, use ATP hydrolysis to power a plethora of functions requiring organization and restructuring of eukaryotic chromosomes in interphase and during mitosis. The Smc5/6 mechanism of action and its activity on DNA are largely unknown. Here we purified the budding yeast Smc5/6 holocomplex and characterized its core biochemical and biophysical activities.

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Double-stranded RNA bending by AU-tract sequences

Sequence-dependent structural deformations of the DNA double helix (dsDNA) have been extensively studied, where adenine tracts (A-tracts) provide a striking example for global bending in the molecule. However, in contrast to dsDNA, sequence-dependent structural features of dsRNA have received little attention. In this work, we demonstrate that the nucleotide sequence can induce a bend in a canonical Watson-Crick base-paired dsRNA helix.

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January 2020

January (2020). New paper published in Nucleic Acids Research on the Dynamics of DNA Nicking and Undwinding by the RepC-PcrA complex

January (2020). Alejandro participates on the event “Science in the classroom” by giving a guided tour of the CNB facilities and an introduction of our research work to high school students from the IES ¨Ciudad de los Ángeles¨.