Homologous recombination

DNA repair deficiencies are characteristic of cancer and homologous recombination deficiency (HRD) is the most common. HRD sensitizes tumour cells to PARP inhibitors so it is important to understand the landscape of HRD across diferent solid tumour types. Methods: Germline and somatic BRCA mu

13p vielonmusk 21-01-2022 17 2   Download

In this study, we proved that Rad52 and Mus81-Mms4 possess a species-specific functional interaction, indicating that Rad52 and Mus81-Mms4 collaborate in processing of homologous recombination intermediates.

12p tieuthi3006 16-03-2018 60 1   Download

A recombinant lipase cloned from Pseudomonas fragi strain IFO 3458 (PFL) was found to retain significant activity at low temperature. In an attempt to elucidate the structural basis of this behaviour, a model of its three-dimensional structure was built by homology and compared with homologous mesophilic lipases, i.e. the Pseudomonas aeruginosa lipase (45% sequence identity) and Burkholderia cepacia lipase (38%).

8p system191 01-06-2013 48 4   Download

Murine pregnancy-associated plasma protein-A (PAPP-A) cDNA encoding a 1545 amino-acid protein has been cloned. We have also identified and cloned cDNA that encodes a novel variant of PAPP-A, PAPP-Ai, carrying a 29-residue highly basic insert. The point of insertion corresponds to a junction between two exons in the human PAPP-A gene. The human intron flanked by these exons does not encode a homologous corresponding insert, which is unique to the mouse.

10p research12 01-06-2013 42 6   Download

The clinically used beta-lactamase inhibitor clavulanic acid is produced by fermentation of Streptomyces clavuligerus. The orf6 gene of the clavulanic acid biosynthetic gene cluster in S. clavuligerus encodes a protein that shows sequence homology to ornithine acetyltransferase (OAT), the fifth enzyme of the arginine biosynthetic pathway. Orf6 was overexpressed in Escherichia coli (at  15% of total soluble protein by SDS/PAGE analysis) indicating it was not toxic to the host cells. The recombinant protein was purified (to 95% purity) by a one-step technique.

8p research12 01-06-2013 33 5   Download

Pycnoporus cinnabarinuslaccaselac1genewasoverexpressed in Aspergillus niger, a well-known fungal host producing a large amount of homologous or heterologous enzymes for industrial applications. The corresponding cDNA was placed under the control of the glyceraldehyde-3-phosphate dehydrogenase promoter as a strong and constitutive pro-moter. The laccase signal peptide or the glucoamylase preprosequence ofA.

8p research12 23-04-2013 50 5   Download

Testican-1, a secreted proteoglycan enriched in brain, has a single thyropin domain that is highly homologous to domains previously shown to inhibit cysteine proteases. We demonstrate that purified recombinant human testican-1 is a strong competitive inhibitor of the lysosomal cysteine pro-tease, cathepsin L,withaKiof 0.7nM, but it does not inhibit the structurally related lysosomal cysteine protease cathep-sin B. Testican-1 inhibition of cathepsin L is independent of its chondroitin sulfate chains and is effective at both pH 5.5 and7.2.

8p tumor12 20-04-2013 33 4   Download

Sequence analysis of aPaenibacillussp. BP-23 recombinant clone coding for a previously described endoglucanase revealed the presence of an additional truncated ORF with homology to family 48 glycosyl hydrolases. The corres-ponding 3509-bp DNA fragment was isolated after gene walking and cloned inEscherichia coliXl1-Blue for expres-sion and purification. The encoded enzyme, a cellulase of 1091 amino acids with a deduced molecular mass of 118 kDa and a pI of 4.

7p fptmusic 16-04-2013 50 3   Download

RecA protein plays a pivotal role in homologous recombination inEscheri-chia coli. RecA polymerizes on single-stranded (ss) DNA forming a nucleo-protein filament. Then double-stranded (ds) DNA is bound and searched for segments homologous to the ssDNA. Finally, homologous strands are exchanged, a new DNA duplex is formed, and ssDNA is displaced. We report a quantitative analysis of RecA interactions with ss d(pN)n of var-ious structures and lengths using these oligonucleotides as inhibitors of RecA filamentation on d(pT)20....

0p awards 06-04-2013 34 3   Download

Geodin is a protein encoded by a sponge gene homologous to genes from the bc-crystallins superfamily. The interest for this crystallin-type protein stems from the phylogenesis of porifera, commonly called sponges, the earliest divergence event in the history of metazoans. Here we report the preparation of geodin as a recombinant protein fromEscherichia coli, its characterization through physico-chemical analyses, and a model of its 3D structure based on homology modelling.

13p awards 05-04-2013 55 4   Download

Searching for bioactive peptides, we analyzed acidic extracts ofPhyllomedusa sauvagiiskin and found two new proteins, PSKP-1 and PSKP-2, of 6.7 and 6.6 kDa, respectively, which, by sequence homology, belong to the Kazal family of serine protease inhibitors. PSKP-1 and PSKP-2 exhibit the unprecedented feature of having proline at P1and P2 positions. A gene encoding PSKP-1 was synthesized and expressed in Escherichia coli. Recombinant PSKP-1 was purified from inclusion bodies, oxidatively refolded to the native state, and characterized by chemical, hydrodynamic andoptical studies. ...

10p dell39 03-04-2013 41 4   Download

Rad51 and disrupted meiotic cDNA1 (Dmc1) are the two eukaryotic DNA recombinases that participate in homology search and strand exchange reactions during homologous recombination mediated DNA repair. Rad51 expresses in both mitotic and meiotic tissues whereas Dmc1 is confined to meiosis.

10p inspiron33 26-03-2013 54 5   Download

The human Rad51 protein, a eukaryotic ortholog of the bacterial RecA protein, is a key enzyme that functions in homologous recombination and recombinational repair of double strand breaks. The Rad51 protein con-tains two flexible loops, L1 and L2, which are proposed to be sites for DNA binding, based on a structural comparison with RecA.

12p inspiron33 25-03-2013 31 2   Download

Arabidopsis thalianacontains eight glutathione peroxidase (GPX) homologs (AtGPX1–8). Four mature GPX isoenzymes with different subcellular dis-tributions, AtGPX1, -2, -5 and -6, were overexpressed in Escherichia coli and characterized. Interestingly, these recombinant proteins were able to reduce H2O2, cumene hydroperoxide, phosphatidylcholine and linoleic acid hydroperoxides using thioredoxin but not glutathione or NADPH as an electron donor.

9p inspiron33 23-03-2013 41 6   Download

DNA topoisomerase 6 (TOP6) belongs to a novel family of type II DNA topoisomerases present, other than in archaebacteria, only in plants. Here we report the isolation of full-length cDNAs encoding putative TOP6 sub-units A and B from rice (Oryza sativassp.indica), preserving all the struc-tural domains conserved among archaebacterial TOP6 homologs and eukaryotic meiotic recombination factor SPO11.

16p inspiron33 23-03-2013 41 4   Download

In eukaryotes, meiosis leads to genetically variable gametes through recom-bination between homologous chromosomes of maternal and paternal ori-gin. Chromatin organization following meiotic recombination is critical to ensure the correct segregation of homologous chromosomes into gametes. However, the mechanism of chromatin organization after meiotic recombi-nation is unknown.

10p media19 06-03-2013 43 2   Download

We report the characterization of the pyrimidine-specific ribonucleoside hydrolase from the hyperthermophilic archaeon Sulfolobus solfataricus (SsCU-NH). The gene SSO0505 encoding SsCU-NH was cloned and expressed in Escherichia coliand the recombinant protein was purified to homogeneity.

15p media19 06-03-2013 34 2   Download

Homologous recombination is a very important cellular process, as it pro-vides a major pathway for the repair of DNA double-strand breaks. This complex process is affected by many factors within cells. Here, we have studied the effect of monovalent cations (K + ,Na + , and NH4 + ) on the outcome of recombination events, as their presence affects the biochemical activities of the proteins involved in recombination as well as the structure of DNA.

11p viettel02 22-02-2013 39 3   Download

EVL is a member of the ENA⁄VASP family, which is involved in actin-remodeling processes. Previously, we reported that human EVL directly interacts with RAD51, which is an essential protein in the homologous recombinational repair of DNA double-strand breaks, and stimulates RAD51-mediated recombination reactionsin vitro.

8p viettel02 20-02-2013 37 3   Download

The Mhr1 protein is necessary for mtDNA homologous recombination in Saccharomyces cerevisiae. Homologous pairing (HP) is an essential reaction during homologous recombination, and is generally catalyzed by the RecA⁄Rad51 family of proteins in an ATP-dependent manner. Mhr1 cata-lyzes HP through a mechanism similar, at the DNA level, to that of the RecA⁄Rad51 proteins, but without utilizing ATP.

13p mobifone23 18-01-2013 34 5   Download