Analysis of Nucleotide Insertion Opposite 2,2,4-Triamino-5(2<i>H</i>)‑oxazolone by Eukaryotic B- and Y‑Family DNA Polymerases

Mutations induced by oxidative DNA damage can cause diseases such as cancer. In particular, G:C–T:A and G:C–C:G transversions are caused by oxidized guanine and have been observed in the <i>p53</i> and <i>K-ras</i> genes. We focused on an oxidized form of guanine, 2,2,4-triamino-5­(2<i>H</i>)-oxazolone (Oz), as a cause of G:C–C:G transversions based on our earlier elucidation that DNA polymerases (Pols) α, β, γ, ε, η, I, and IV incorporate dGTP opposite Oz. The nucleotide insertion and extension of Pols δ, ζ, ι, κ, and REV1, belonging to the B- and Y-families of DNA polymerases, were analyzed for the first time. Pol δ incorporated dGTP, in common with other replicative DNA polymerases. Pol ζ incorporated dGTP and dATP, and the efficiency of elongation up to full-length beyond Oz was almost the same as that beyond G. Although nucleotide incorporation by Pols ι or κ was also error-prone, they did not extend the primer. On the other hand, the polymerase REV1 predominantly incorporated dCTP opposite Oz more efficiently than opposite 8-oxo-7,8-dihydroguanine, guanidinohydantoin, or tetrahydrofuran. Here, we demonstrate that Pol ζ can efficiently replicate DNA containing Oz and that REV1 can prevent G:C–C:G transversions caused by Oz

Effect of cataract surgery on cognitive function in elderly: Results of Fujiwara-kyo Eye Study

<div><p>Purpose</p><p>To determine whether there is a significant association between prior cataract surgery and cognitive function in an elderly Japanese cohort.</p><p>Setting</p><p>Nara Medical University, Nara, Japan.</p><p>Design</p><p>The Fujiwara-kyo Eye Study was a cross-sectional epidemiological study.</p><p>Methods</p><p>The subjects were ≥ 68-years who lived in the Nara Prefecture and responded to recruitment notices. All of the subjects received comprehensive ophthalmological examinations, and answered questionnaires on their socio-demographic and medical history including prior cataract surgery. The association between prior cataract surgery and cognitive function was determined.</p><p>Results</p><p>A total of the 2764 subjects whose mean age was 76.3±4.8 years (±standard deviation) was studied. Of these, 668 individuals (24.2%) had undergone cataract surgery. Of these, 150 (5.4%) had dementia as determined by the Mini-Mental State Examination (MMSE) score ≤23, and 877 individuals (31.7%) had mild cognitive impairment (MCI; MMSE score 24–26). The subjects who had prior cataract surgery had significantly lower odds ratio (OR) of having MCI (OR = 0.78, 95% confidence interval; CI 0.64–0.96, <i>P</i> = 0.019) than those who had not had cataract surgery after adjusting for age, sex, body mass index, education, hypertension, diabetes, depression, and history of stroke. The OR was still lower when the visual acuity was also added to the adjusted factors (OR 0.79, 95% CI 0.64–0.97, <i>P</i> = 0.025). However, prior cataract surgery did not contribute significantly to the low OR for dementia.</p><p>Conclusions</p><p>Cataract surgery may play a role in reducing the risk of developing MCI independently of visual acuity but not for dementia.</p></div

Odds ratio for association between cataract surgery and cognitive status.

<p>Odds ratio for association between cataract surgery and cognitive status.</p

MOESM1 of The interaction effect between physical and cultural leisure activities on the subsequent decline of instrumental ADL: the Fujiwara-kyo study

Additional file 1: Table S1. Baseline characteristics by the completion of follow-up assessment of IAD

Basic and clinical characteristics of 2764 participants by cognitive status.

<p>Basic and clinical characteristics of 2764 participants by cognitive status.</p

Associations between visual acuity and cognitive impairment by cataract status.

<p>Associations between visual acuity and cognitive impairment by cataract status.</p

Additional file 1 of Analysis of nucleotide insertion opposite urea and translesion synthesis across urea by DNA polymerases

Additional file 1: Fig. S1. Construction of the 30-merUa. Two products (30-merUa1 and 30-merUa2) were obtained (Materials and methods). However, these two products equilibrate with each other and thus could not be isolated separately. In a previous report [7], Dubey, et al. revealed that Ua comprises the α- and β-anomers. The mixture of the two products (C289H370N103O176P29) was confirmed by ESI-MS (m/z 9000.727) and then was used as 30-merUa in our experiment

Additional file 2 of Analysis of nucleotide insertion opposite urea and translesion synthesis across urea by DNA polymerases

Additional file 2: Fig. S2. DNA synthesis across urea (Ua) by Kf exo−. DNA synthesis in Fig. S2 was conducted under the same condition as in Fig. 2C. Kf exo− (75 μU) was incubated with templates containing G (lane 3) or Ua (lane 4) and 100 μM of each of the four dNTPs (lanes 1–4). Lanes 1 and 2 contained no enzyme and are negative controls. The background darkness of panel A is adjusted in Panel B. Fig. S3. DNA synthesis across urea (Ua) by DNA polymerase η. DNA synthesis in Fig. S3 was conducted under the same condition as in Fig. 4B. DNA polymerase η (0.4 ng) was incubated with templates containing G (lane 2) or Ua (lane 4) and 100 μM of each of the four dNTPs (lanes 1, 2, 4 and 5). Lanes 1 and 5 contained no enzyme and are negative controls. The sample in lane 3 was a mixture of the samples in lanes 2 and 4

G‑Quadruplex DNA- and RNA-Specific-Binding Proteins Engineered from the RGG Domain of TLS/FUS

Human telomere DNA (Htelo) and telomeric repeat-containing RNA (TERRA) are integral telomere components containing the short DNA repeats d­(TTAGGG) and RNA repeats r­(UUAGGG), respectively. Htelo and TERRA form G-quadruplexes, but the biological significance of their G-quadruplex formation in telomeres is unknown. Compounds that selectively bind G-quadruplex DNA and RNA are useful for understanding the functions of each G-quadruplex. Here we report that engineered Arg-Gly-Gly repeat (RGG) domains of translocated in liposarcoma containing only Phe (RGGF) and Tyr (RGGY) specifically bind and stabilize the G-quadruplexes of Htelo and TERRA, respectively. Moreover, RGGF inhibits trimethylation of both histone H4 at lysine 20 and histone H3 at lysine 9 at telomeres, while RGGY inhibits only H3 trimethylation in living cells. These findings indicate that G-quadruplexes of Htelo and TERRA have distinct functions in telomere histone methylation

Demographic and diagnostic data of the participants.

<p>NC, normal controls; SCI, subjective cognitive impairment; MCI, mild cognitive impairment; AD, Alzheimer's disease; GDS, Global Deterioration Scale; MMSE, Mini Mental State Examination; ADAS-Cog., Alzheimer's disease assessment scale - cognitive subscale; WMS-R, Wechsler memory scale - revised; N.S., not significant; DWMH, deep white matter hyperintensity; ChEI, cholinesterase inhibitor.</p><p>*χ² test, **GDS; stage 4, n = 25, stage 5, n = 14, ***one way analysis of variance, ****lack of one subject's data.</p