Xiu, X. | Search bioRxiv

bioRxiv2022

Programming super DNA-enzyme molecules for on-demand enzyme activity modulation

Dynamic interactions of enzymes, including programmable configuration and cycling of enzymes, play important roles in the regulation of cellular metabolism. Here, we construct a super DNA-enzymes molecule (SDEM) that comprises at least two cascade enzymes and linked DNA strands to control and detect metabolism. We find that the programmable SDEM which comprises glucose oxidase (GOx) and horseradish peroxidase (HRP) has a 50-fold lower detection of limit and a 1.6-fold higher reaction rate than free enzymes. SDEM can be assembled and disassembled using a hairpin structure and a displacement DNA strand to complete multiple cycles. An entropically driven catalytic assembly (catassembly) enables different SDEMs to switch from SDEM with GOx and HRP cascades to SDEM with sarcosine oxidase (SOX) and HRP cascades by over six orders of magnitude less time than no catassembly to detect different metabolisms (glucose and sarcosine) on demand.

biochemistry↗

bioRxiv2021

The putative causal effect of type 2 diabetes in risk of cataract: a Mendelian randomization study in East Asian

BackgroundThe epidemiological association between type 2 diabetes and cataract has been well-established. However, it remains unclear whether the two diseases share a genetic basis, and if so, whether this reflects a causal relationship. MethodsWe utilized East Asian population-based genome-wide association studies (GWAS) summary statistics of type 2 diabetes (Ncase=36,614, Ncontrol=155,150) and cataract (Ncase=24,622, Ncontrol=187,831) to comprehensively investigate the shared genetics between the two diseases. We performed 1. linkage disequilibrium score regression (LDSC) and heritability estimation from summary statistics ({rho}-HESS) to estimate the genetic correlation and local genetic correlation between type 2 diabetes and cataract; 2. multiple Mendelian randomization (MR) analyses to infer the putative causality between type 2 diabetes and cataract; and 3. Summary-data-based Mendelian randomization (SMR) to identify candidate risk genes underling the causality. ResultsWe observed a strong genetic correlation (rg=0.58; p-value=5.60x10-6) between type 2 diabetes and cataract. Both {rho}-HESS and multiple MR methods consistently showed a putative causal effect of type 2 diabetes on cataract, with estimated liability-scale MR odds ratios (ORs) at around 1.10 (95% confidence interval [CI] ranging from 1.06 to 1.17). In contrast, no evidence supports a causal effect of cataract on type 2 diabetes. SMR analysis identified two novel genes MIR4453HG ({beta}SMR=-0.34, p-value=6.41x10-8) and KCNK17 ({beta}SMR=-0.07, p-value=2.49x10-10), whose expression levels were likely involved in the putative causality of type 2 diabetes on cataract. ConclusionsOur results provided robust evidence supporting a causal effect of type 2 diabetes on the risk of cataract in East Asians, and posed new paths on guiding prevention and early-stage diagnosis of cataract in type 2 diabetes patients. Key MessagesO_LIWe utilized genome-wide association studies of type 2 diabetes and cataract in a large Japanese population-based cohort and find a strong genetic overlap underlying the two diseases. C_LIO_LIWe performed multiple Mendelian randomization models and consistently disclosed a putative causal effect of type 2 diabetes on the development of cataract. C_LIO_LIWe revealed two candidate genes MIR4453HG and KCNK17 whose expression levelss are likely relevant to the causality between type 2 diabetes and cataract. C_LIO_LIOur study provided theoretical fundament at the genetic level for improving early diagnosis, prevention and treatment of cataract in type 2 diabetes patients in clinical practice C_LI

genetics↗