To unwind the biological knots: The DNA/RNA G-quadruplex resolvase RHAU (DHX36) in development and disease.

The G-quadruplex (G4) sequences are short fragments of 4-interval triple guanine (G) with frequent and ubiquitous distribution in the genome and RNA transcripts. The G4 sequences are usually folded into secondary "knot" structure via Hoogsteen hydrogen bond to exert negative regulation on a variety of biological processes, including DNA replication and transcription, mRNA translation, and telomere maintenance. Recent structural biological and mouse genetics studies have demonstrated that RHAU (DHX36) can bind and unwind the G4 "knots" to modulate embryonic development and postnatal organ function. Deficiency of RHAU gives rise to embryonic lethality, impaired organogenesis, and organ dysfunction. These studies uncovered the pivotal G4 resolvase function of RHAU to release the G4 barrier, which plays fundamental roles in development and physiological homeostasis. This review discusses the latest advancements and findings in deciphering RHAU functions using animal models.

The Expression of miR-365 in Serum of Hypertension Patients with Left Ventricular Hypertrophy Was Up-Regulated, Which Was Positively Correlated with Left Ventricular Mass Index.

OBJECTIVE: The present study aims to investigate micro ribonucleic acid-365 (miR-365) serum expression and its correlation with left ventricular hypertrophy (LVH) in patients with hypertension (HT). METHODS: Eighty-four patients were selected as study subjects and divided into three groups: the experimental group (n = 28), the observation group (n = 29), and the control group (n = 27). The experimental group included patients with LVH-accompanied HT who were treated in the People's Hospital of Hebei Province between November 2019 and November 2020, the observation group included patients with HT unaccompanied by LVH, and the control group included healthy age and gender-matched subjects who underwent health examinations in our physical examination center. The cardiac echocardiography, 24-h Holter electrocardiogram, and circulating miR-365 levels in all subjects were measured. The differences in circulating miR-365 expression levels among the three groups were compared, and the correlations between the miR-365 expression levels and the blood pressure parameters (24-h mean systolic blood pressure [SBP] and 24-h mean diastolic blood pressure [DBP]), inter-ventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), left ventricular internal diameter (LVID), left ventricular mass (LVM), LVM index (LVMI), and LVH-related indicators were analyzed. RESULTS: The relative miR-365 expressions in the experimental, observation, and control groups were 2.08 (1.60, 2.34), 0.62 (0.44, 0.83), and 0.66 (0.35, 0.86), respectively. Patient miR-365 expression was significantly higher in the experimental group than in the observation group and the control group; the differences were statistically significant (p < 0.000). Furthermore, miR-365 expression was significantly correlated with SBP, DBP, IVST, LVPWT, LVID, LVM, and LVMI; the greatest correlation was with LVMI. Further univariate linear regression analysis revealed that miR-365 expression was linearly and positively correlated with LVMI and that miRNA-365 expression increased with the LVMI value. CONCLUSION: The miR-365 serum expression in patients with LVH-accompanied HT was increased compared with the observation group and the control group and positively correlated with the LVH degree.